Rajasthan's Climate: Characteristics, Regions and the Monsoon

Climate rose from 2.5% of the Geography unit in the older RAS papers to 7.9% in the recent ones, and it has appeared in every paper since 2018. Almost none of it is descriptive. The questions are about mechanism (why the desert is where it is), about classification (Koppen's letters), and about gradient (which district is wetter than which).

The single most useful sentence in this chapter is not a figure. The Aravalli runs south-west to north-east. The Arabian Sea branch of the south-west monsoon travels south-west to north-east. A barrier that lies along the direction of travel is not a barrier at all, and three-fifths of Rajasthan is dry because of that one geometric accident.

1. Why Rajasthan is dry

Four things decide Rajasthan's climate, and only one of them is unusual.

Latitude. The state lies between about 23°3′ N and 30°12′ N. The Tropic of Cancer clips only the extreme south, through Banswara and Dungarpur, so almost the whole state is sub-tropical rather than tropical. High sun angles in May and June, and a large annual swing.

Distance from the sea. Rajasthan touches no coast. Continentality gives it hot summers, cold winters and a large daily range, because there is no water body nearby to store heat and release it slowly.

Low relief. More than half the state lies between 150 and 300 metres. Air that is not forced to rise does not cool, and air that does not cool does not condense. The western plain offers the monsoon nothing to climb.

And the alignment of the Aravalli, which is the part worth thinking about rather than memorising.

The geometry that matters

The Arabian Sea branch of the south-west monsoon splits into three. One branch is stopped by the Western Ghats and drenches the west coast. A second enters along the Narmada and Tapi valleys. The third strikes Saurashtra and Kachchh, and then, in NCERT's own words, "passes over west Rajasthan and along the Aravallis, causing only a scanty rainfall."

Compare it with a case NCERT explains directly. The Tamil Nadu coast stays dry during the south-west monsoon for two reasons, and the first is that "the Tamil Nadu coast is situated parallel to the Bay of Bengal branch of southwest monsoon." Parallelism is a recognised mechanism for dryness in Indian climatology, not a coaching invention. Rajasthan's Aravalli is the same mechanism applied to a mountain range instead of a coastline.

What a perpendicular range would have done. A barrier standing across the flow forces the air up, the air cools, the moisture condenses, and rain falls on the windward slope. That is the Western Ghats. The Aravalli, lying along the flow, forces nothing up. The winds run beside it and past it, losing moisture only slowly, and the state receives what a range in that position can give, which is very little.

The Bay of Bengal branch fails Rajasthan for a different reason. It arrives from the east, having already rained over the Gangetic plain, and reaches the state's eastern districts with what moisture is left. That is why the rain in Rajasthan comes mostly from the east and south-east and thins out to the north-west. The Aravalli explains the failure of the western supply; exhaustion explains the weakness of the eastern one.

GovtSources: NCERT, India: Physical Environment, Class XI, chapter 4 "Climate" (2026-27 reprint), for the three-way split of the Arabian Sea branch, the branch that passes over west Rajasthan and along the Aravallis causing only scanty rainfall, and the Tamil Nadu coast parallel to the Bay of Bengal branch. Government of Rajasthan, Rajasthan State Action Plan on Climate Change 2022 (Department of Environment and Climate Change, prepared with Climate Studies, IIT Bombay), for the Aravalli dividing the state into two climatic zones, arid to semi-arid west of the range and semi-arid to sub-humid east of it, with large extremes of temperature, long periods of drought, high wind velocity and high potential evapotranspiration.

MCQ WATCH — the Aravalli's alignment

Direct fact: the Aravalli runs south-west to north-east; the Arabian Sea branch travels south-west to north-east; the range is therefore along that flow, not across it. The result is that the branch delivers scanty rainfall over west Rajasthan.

The trap that has actually been set: RAS Prelims 2018, Q28 asked what causes the May and June dust storms of Rajasthan and offered "Aravalli hills are parallel to south-western winds" as one of three statements. RPSC's key accepted only "origin of convectional currents at few places". Read the question carefully before concluding that the key denies the alignment. The alignment explains the rainfall deficit; it does not explain the dust storms, which are convective. A statement can be true and still be the wrong answer to the question asked.

The complementary fact, also set: RAS Prelims 2016, Q35 established that the Aravalli DOES affect the distributional pattern of rainfall in Rajasthan and that it restricts the eastward expansion of the desert. Hold both: the range decides where the rain falls, and it does so by failing to catch the western branch while sheltering nothing from the eastern one.

Easily confused: the Aravalli's effect on rainfall is not a rain-shadow effect in the Western Ghats sense. There is no wet windward side. The range is dry on both flanks near its crest; the difference between the two flanks is one of degree, produced by how far the eastern branch penetrates.

2. The seasons

The number of seasons Rajasthan has depends on which government you ask, and this is not a trivial disagreement. Three official divisions are in circulation, and they do not agree on how many seasons there are or when winter ends.

GovtSources: NCERT, India: Physical Environment, Class XI, chapter 4, which states that "the meteorologists recognise the following four seasons"; Government of Rajasthan, State Action Plan on Climate Change 2022; India Meteorological Department, Climate of Jaipur (Meteorological Centre Jaipur, 1 January 2011, by Ajit Tyagi, O. P. Singh, S. S. Singh and Surender Kumar); Government of Rajasthan, Rajasthan Foundation — Weather. The four divisions are printed as their sources print them and are not reconciled here, because they are built for different purposes and no arithmetic can merge them.

Give the four-fold division unless a question says otherwise, because that is the division RPSC's syllabus vocabulary and the standard textbooks use. But know that the state's own climate-change plan uses three, and that its winter runs October to February, which would make October a winter month rather than a post-monsoon one.

What the temperature actually does

These are IMD's own 1991-2020 normals for its ten Rajasthan observatories. They are the most defensible temperature figures available for the state, and they settle several questions that circulate on guesswork.

GovtSource: India Meteorological Department, Meteorological Centre Jaipur, station extremes and climatological information — the "Climatological Information" table in each station file, period 1991-2020. Files read: Ajmer (42343), Barmer (42435), Bikaner (42165), Churu (42170), Jaipur (42348), Jaisalmer (42328), Jodhpur (42339), Kota (42452), Ganganagar (42123) and Dabok/Udaipur (42542). The annual mean daily range is arithmetic on IMD's two columns, not a published figure. IMD's Udaipur observatory is at Dabok and its file is titled accordingly.

Three findings follow from that table, and each of them corrects something widely taught.

January is the coldest month at every one of the ten stations. No exceptions, no borderline cases. A question offering December is offering the wrong month.

May, not June, is the hottest month at every one of the ten stations, measured by mean daily maximum. Churu 42.6 against 41.7 in June; Jaisalmer 42.1 against 41.1; Barmer 42.3 against 40.8; Kota 42.6 against 40.3. The mechanism is the monsoon: by mid-June cloud and the first rain have begun to cap the daytime maximum, even where the rain itself has not arrived. Preparation material routinely gives June as the hottest month. The individual record highs have been set in both May and June, which is probably where the confusion starts, but the normals are unambiguous and they are IMD's.

Churu has the coldest January and the largest annual mean daily range. Its January nights average 5.6 °C and its May afternoons 42.6 °C, a spread of 37 kelvin across the year, on a mean daily range of 15.8 K. This is what continentality over sand looks like, and it is why Churu appears in both heat-wave and cold-wave news in the same twelve months. Kota sits at the other end: the smallest daily range in the set, 11.3 K, because the Hadoti plateau is wetter and more humid, and water in the air damps the swing.

The winds and the local vocabulary

Loo. NCERT defines it as "hot, dry and oppressing winds" blowing in the northern plains, and places it in the heart of the summer low-pressure trough, which extends over the Thar. It blows in the afternoon and often continues well into midnight.

Dust storms. NCERT records that dust storms in the evening are very common during May in Punjab, Haryana, eastern Rajasthan and Uttar Pradesh, and that they bring light rain and a cool breeze. RPSC keyed their cause as convectional currents, which is the same mechanism stated differently: a superheated surface drives air upward, and the rising column drags dust with it.

Mawath (also spelt Mawat, Mahawat). Winter rain, caused by western disturbances, extratropical systems arriving from the Mediterranean. RPSC has keyed this directly, in Prelims 2013. Its importance is out of all proportion to its quantity, because it falls on the standing rabi crop. The IMD normals show exactly where it matters most, which is section 3.

October heat. NCERT's term for the retreating monsoon season: clear skies, rising temperature, land still moist, and weather that becomes "rather oppressive." Rajasthan's version is often called Kartik heat. Note what causes it. The rain stops before the sun weakens, so temperature climbs while humidity is still high, and the combination is worse than either alone.

GovtSources: NCERT, India: Physical Environment, Class XI, chapter 4, for the Loo, the May dust storms and the October heat. Mawath's cause is RPSC's own key (RAS Prelims 2013, Q34), reproduced in the PYQ page.

MCQ WATCH — seasons and temperature

Direct fact: coldest month January, at all ten IMD observatories. Hottest month May by mean daily maximum, at all ten. Coldest station Churu (January mean minimum 5.6 °C); largest annual mean daily range Churu (15.8 K); smallest Kota (11.3 K).

Statement-based trap: "June is the hottest month in Rajasthan" is false on IMD's normals and widely printed as true. If an option pair forces a choice, June carries the record highs and May carries the highest normal. Read whether the question asks about a record or an average.

The season count: if asked how many seasons Rajasthan has, four is the answer to give. But the state's own SAPCC 2022 uses three and runs winter from October to February. Do not treat the three-season version as an error; it is the Environment Department's.

Vocabulary that separates: Mawath = winter rain from western disturbances. Loo = hot dry summer wind. October or Kartik heat = the oppressive spell during the monsoon's retreat, high temperature with residual humidity. An option offering "north-east monsoon" as the cause of mawath is wrong by definition, and it has been offered.

3. Rainfall: the gradient, and where the 50 cm line runs

Rainfall in Rajasthan falls from the south-east to the north-west. This one gradient answers more RAS questions than any figure in this chapter, and RPSC has set it in both directions, descending in 2023 and ascending in 2024.

The two halves of the state, as IMD measures them

IMD divides Rajasthan into two meteorological sub-divisions, and their normals are the cleanest expression of the gradient available.

GovtSource: India Meteorological Department, Meteorological Centre Jaipur, Rajasthan Monsoon Report 2025, Tables 3 to 5. Long period averages are on 1971-2020 data. These are south-west monsoon season figures, June to September, not annual totals.

East Rajasthan receives 2.2 times what West Rajasthan receives, in the same four months. That ratio, not the individual numbers, is the thing to carry.

The monthly normals inside those totals contain a detail worth having. For the state as a whole and for West Rajasthan, July is the wettest month (161.4 mm statewide, 107.8 mm in the west). In East Rajasthan, August is marginally wetter than July, 231.5 mm against 228.6 mm. The eastern half's rain is delivered by the Bay of Bengal branch, which peaks later.

Annual normals, station by station

The monsoon-season figures above understate the western districts' dependence on winter rain. These are the full annual normals.

GovtSource: India Meteorological Department, Meteorological Centre Jaipur, station climatological information, 1991-2020. The annual totals and rainy-day counts are IMD's; the June-to-September sums and the percentage shares are arithmetic on IMD's monthly columns and are not published figures. Each station's twelve monthly values were checked against IMD's own annual total before use, and every one reconciles to within 0.2 mm.

Read the last column, because it is the part nobody teaches. The claim that Rajasthan gets over 90% of its rain from the south-west monsoon is true in the south-east and false in the north-west. Kota takes 92% of its rain from the monsoon and Udaipur 93%. Sri Ganganagar and Bikaner take only 76%. Roughly a quarter of the rainfall of the far north-west arrives outside the monsoon, and most of that is mawath.

That is the quantitative case for mawath. Sri Ganganagar's January and February normals alone are 7.8 mm and 15.3 mm, against Udaipur's 3.0 mm and 1.3 mm. Winter rain is a north-western phenomenon, and the districts that need it most for wheat and mustard are exactly the ones that get it.

And note the rainy-day column. Jaisalmer has 13.1 rainy days a year; Kota has 38.6. The desert is not merely drier, it is dry on more days, which is a different agricultural problem from low totals alone.

The 50 cm line

The dividing line between "low rainfall" and "inadequate rainfall" India, drawn by NCERT, runs through Rajasthan.

GovtSource: NCERT, India: Physical Environment, Class XI, chapter 4 "Climate" (2026-27 reprint). The 50 cm figure is the boundary between two of NCERT's four national rainfall classes, and Rajasthan is the only state that NCERT splits across that boundary by name.

The 50 cm isohyet is therefore not a Rajasthan convention; it is the national line, and it happens to pass through the state. It runs broadly along the Aravalli, which is why the range is described as separating the eastern plains from the desert. The IMD station normals put the line where you would expect it: Jodhpur at 370 mm and Churu at 426 mm sit below it, Ajmer at 571 mm and Jaipur at 600 mm above it.

Two more lines are worth knowing as concepts rather than as data. The 25 cm isohyet is treated as the boundary between arid and semi-arid desert, and the 40 cm isohyet as the line that divides the state into roughly two halves. Both are standard in Rajasthan preparation material. No Government of Rajasthan or IMD document stating them in those terms was located, and they are recorded in Aggregator Watch rather than asserted here.

MCQ WATCH — rainfall

The gradient, in one line: south-east wettest, north-west driest. RPSC has set it descending (2023: Dholpur > Rajsamand > Jalore) and ascending (2024: Jalore < Jaipur < Kota). Learn the direction and you do not need the numbers.

Direct facts: seasonal normal 435.6 mm for the state, 626.6 mm East Rajasthan, 283.6 mm West Rajasthan, all June to September, IMD 1971-2020. Annual average around 572 mm, which is the Government of Rajasthan's figure in the SAPCC 2022 and includes non-monsoon rain.

The number-pair trap: 435.6 mm and 572 mm are not in conflict. One is a four-month normal, the other an annual average. An option pairing either with the wrong period is the standard trap.

The 50 cm line: below 50 cm is most of western Rajasthan; 50 to 100 cm is eastern Rajasthan. That is NCERT's national classification, not a state one.

Statement-based trap: "Over 90% of Rajasthan's rainfall comes from the south-west monsoon" is true for the south-east and false for the north-west on IMD's own normals, where Sri Ganganagar and Bikaner are at 76%. If the statement is about the state as a whole it is defensible; if it is about the desert districts it is not.

4. Koppen's classification, and what the arithmetic actually gives

Koppen classifies climate from temperature and precipitation thresholds, using letters. The letters that occur in Rajasthan are these.

Note at once that D and E types, cold and polar, do not occur in Rajasthan. That is a stated non-fact worth holding, because it eliminates options.

The four types RPSC recognises

RPSC has set Koppen's Rajasthan types repeatedly, and its 2021 key is the authoritative statement of what the examiner accepts.

GovtSource: RPSC's own answer key to RAS Prelims 2021, Q58, reproduced with the full question on the Geography of Rajasthan PYQ page. The key accepts Cwg–Bharatpur and Aw–Dungarpur and rejects Bwhw–Barmer and Bshw–Ganganagar. The names and letter definitions are Koppen's scheme itself. No Government of Rajasthan or Government of India document giving a district-wise Koppen map of Rajasthan was located, which is why this table is anchored to the examiner's key rather than to a departmental publication.

The classification worked out from IMD's normals

Koppen's aridity test can be applied directly to IMD's published station normals, and doing so is more instructive than memorising a map. The test, in the standard modern form: compute the annual mean temperature T, take P = 2T + 28 for a station whose rain falls in the summer half, and then desert (BW) if the annual rainfall is below 5P, steppe (BS) if it is between 5P and 10P, and not a B climate at all above 10P. Add h wherever the annual mean temperature is above 18 °C.

This table is arithmetic, not a published classification. The inputs are IMD's 1991-2020 station normals; the thresholds are Koppen's own criteria in the Koppen-Geiger form. Annual mean temperature is taken as the midpoint of IMD's annual mean daily maximum and mean daily minimum, which is the standard approximation and not a figure IMD itself publishes. A different normal period, or a different variant of Koppen's threshold formula, moves stations that sit near a boundary.

Three things follow, and they are worth more than the map.

Every one of IMD's ten Rajasthan observatories is a B climate. None reaches Aw or Cwg on these normals. Aw and Cwg exist in Rajasthan in the districts IMD does not staff an observatory in — Banswara, Dungarpur, Jhalawar and Bharatpur — where the rainfall is higher.

Kota misses being a non-arid climate by 13 millimetres. Its annual rainfall of 816.2 mm sits just under its own 829 mm steppe threshold. The wettest IMD station in Rajasthan is, by Koppen's arithmetic, still semi-arid. That is the most economical statement of what kind of state this is.

And the arithmetic agrees with RPSC's key on one rejected pair and not the other. Sri Ganganagar computes as BWh, not BShw, which supports the key's rejection of "BShw–Ganganagar". Barmer also computes as BWh, which does not support the key's rejection of "BWhw–Barmer". In the exam the key governs. The disagreement is recorded rather than smoothed, because Koppen boundaries move with the data period and Barmer at 304 mm against a 420 mm desert threshold is not a marginal case on 1991-2020 data.

Thornthwaite

Thornthwaite classifies by a moisture index built from precipitation against potential evapotranspiration, rather than from rainfall alone, and adds a thermal-efficiency letter. That much is the scheme itself and is not in dispute.

A four-type application of Thornthwaite to Rajasthan circulates universally in preparation material, with the codes CA′w, DA′w, DB′w and EA′d and a district list for each. No government or peer-reviewed source setting out that district-wise scheme could be reached for this chapter. It is recorded in Aggregator Watch as what the aggregators say, and it is not asserted here. What can be said, and is standard in the literature, is that Thornthwaite's A and B moisture types, the humid ones, do not occur in Rajasthan, and that the state falls in his D (semi-arid) and E (arid) moisture classes, with the arid E in the far west.

5. The ten agro-climatic zones

This is the state's own operational division of its climate, and it is the one that decides which crop goes where. It is in the current Economic Review, which is where RPSC takes its figures from.

Rajasthan is divided into 10 agro-climatic zones, on climate, soil types, topography and cropping patterns. The Review adds the split that frames the whole unit: the north-western region, 61% of the state, is desert or semi-desert and reliant on rainfall; the south-eastern region, 39%, is fertile.

GovtSource: Government of Rajasthan, Directorate of Economics and Statistics, Economic Review 2025-26, Table 1.2, "Agro-Climatic Zones of Rajasthan", and the accompanying text for the 10 zones and the 61% and 39% split. District names are reproduced as the Review prints them, except that it spells Karauli as "Karoli" and Didwana-Kuchaman as "Deedwana-Kuchaman". The Review's list is on the current district framework and names Phalodi, Balotra, Beawar, Deeg, Salumber, Khairthal-Tijara and Kotputli-Behror, which is why it supersedes every zone table printed before 2023.

Learn the zones by their edges, not their middles. Sirohi is split between two zones, its Pindwara and Abu Road tehsils going to the sub-humid south and the rest to the Luni basin. Churu is split, four tehsils going west into the hyper-arid zone and the rest into inland drainage. Chittorgarh is split, Badi Sadri alone going to the humid south. Beawar is split between the Luni basin and the semi-arid eastern plains. A "which district is in which zone" question is answered wrongly more often on the split districts than on the obvious ones.

Two zones are named for something other than climate and that is the point of them. I-B is "irrigated" and I-C is "partially irrigated": they sit in the same rainfall band as I-A but grow cotton and guar because the Indira Gandhi canal system reaches them. III-B is "flood-prone" in a state defined by drought, because the eastern plains take the Bay of Bengal branch at full strength and the Chambal system concentrates it. Zone names in Rajasthan encode water availability, not water fallen.

Note also that the Economic Review's 61:39 split and the Environment Department's 60:40 split of the state by the Aravalli are two different statements. The Review is dividing by agricultural character, the Environment Department by the watershed of the range. They agree closely, which is reassuring, but they are not the same measurement and neither is derived from the other. The 60:40 figure is treated in the physiography chapter.

6. Records and extremes

Records are where preparation material rots fastest, because a record that was true in 2010 may have been broken since and the note that carries it never was.

Temperature

PrimaryGovtSources: van Oldenborgh, G. J., Philip, S., Kew, S., van Weele, M., Uhe, P., Otto, F., Singh, R., Pai, I., Cullen, H., and AchutaRao, K., "Extreme heat in India and anthropogenic climate change", Natural Hazards and Earth System Sciences, 18, 365-381, 2018, doi:10.5194/nhess-18-365-2018, which states: "On 19 May 2016 the afternoon temperature reached 51.0 °C in Phalodi in the northwest of India — a new record for the highest observed maximum temperature in India." The 1956 Alwar figure of 50.6 °C is the record the 2016 reading replaced. The Churu reading of 50.5 °C on 28 May 2024 was published by IMD on its own channels and is below the Phalodi mark. A refutation check was run against the 2024 heat wave, which produced the highest Indian temperature since 2016 and did not break the record.

Two consequences, and both are examinable.

Phalodi is now a district in its own right. It was in Jodhpur district when the record was set in 2016, and every source written before 2023 places it there. RPSC may key either, and a question naming "Jodhpur district" for the 2016 record is not wrong so much as historical.

Any note giving Alwar 1956 as Rajasthan's highest recorded temperature is a decade out of date. That figure is still printed widely. It was the Indian record; it is not the current one.

Rainfall

GovtSource: India Meteorological Department, Meteorological Centre Jaipur, Rajasthan Monsoon Report 2025, Table 2, "Top Ten monsoon (1901-2025) for Rajasthan". The remaining six of the top ten are 1975 (665.4), 1973 (641.8), 1944 (627.4), 2022 (596.1), 2011 (593.7) and 2019 (583.8). The same report prints the 2025 total twice and differently, 715.2 mm in its Highlights and 715.9 mm in its text and in Table 2. The table value is used here and the discrepancy is stated rather than resolved, because both are IMD's.

Read the table for the pattern rather than the entries. Five of the ten wettest monsoons since 1901 have occurred in 2011 or later — 2011, 2019, 2022, 2024 and 2025 — and two of them are consecutive. That is a fact about the present, and it belongs in a Mains answer on climate variability rather than in a list of records.

The 2025 season's district extremes, from the same report: highest district total Baran, 1,593.5 mm, then Sawai Madhopur, 1,333.1 mm; largest departure Hanumangarh at 227% of its own normal; smallest departure Sirohi at 123%. Twenty of the thirty-three districts recorded large excess rainfall and none recorded deficient or scanty. Note that IMD reports Rajasthan on the thirty-three-district framework, not the current forty-one.

The lowest temperature, which is published

Mount Abu, −7.4 °C, on 12 December 1994. That is the lowest dated station minimum among IMD's Rajasthan observatories, and it is in IMD's own Climatological Tables of Observatories in India 1991-2020 (station 256). Carry one caution with it: the extreme columns in those tables lag, so a colder reading in a later winter would not yet appear there.

Mount Abu is the state's coldest station in ordinary winters as well, not only in this one record: its January mean daily minimum on IMD's 1991-2020 normals is 2.9 °C, against 5.6 °C at Churu, which is the coldest of the ten stations the Meteorological Centre Jaipur publishes.

7. The monsoon's normal dates, and the 2026 season

The normals, and the fact that they were revised

IMD replaced its monsoon onset and withdrawal normals in 2020. The old ones were computed on 1901-1940 data and had been in operational use for eighty years. The new onset normals use 1961-2019 and the new withdrawal normals 1971-2019. For Rajasthan the revision moved the onset a little later and the withdrawal much later.

GovtSource: D. S. Pai, Arti Bandgar, Sunitha Devi, Madhuri Musale, M. R. Badwaik, A. P. Kundale, Sulochana Gadgil, M. Mohapatra and M. Rajeevan, New Normal Dates of Onset/Progress and Withdrawal of Southwest Monsoon over India, India Meteorological Department, Climate Research and Services, Pune, CRS Research Report No. 3/2020, Table 2, "Normal monsoon onset (1961-2019) dates based on new rainfall criteria ... and withdrawal (1961-2019) dates based on the operational data over 140 major cities of the country". The ten stations above are all of IMD's Rajasthan entries in that table. The report's column headings are "Existing (1901-1940)" and "New"; the onset New column is 1961-2019 and the withdrawal New column is 1971-2019.

Read the table across, not down. The onset dates moved by a few days; the withdrawal dates moved by two to three weeks. Barmer's normal withdrawal shifted from 1 September to 20 September, Ajmer's from 8 September to 21 September. The monsoon has not been arriving much later; it has been staying much longer. IMD's own text makes the general statement: withdrawal from north-west India now begins around 17 September against the old normal of 1 September, a delay of more than two weeks.

And read the ordering down the onset column, because it is the gradient again. Jhalawar first on 24 June, Bikaner and Pokharan last on 6 July. Twelve days for the monsoon to cross the state, entering in the south-east and finishing in the far west.

IMD's Meteorological Centre Jaipur states three state-level normals in its annual monsoon reports, and they are the ones to quote for the state as a whole:

• The monsoon covers the entire state by 8 July (normal).
• Withdrawal begins from West Rajasthan around 17 September (normal).
• The monsoon has withdrawn from the entire state by 30 September (normal).

GovtSource: IMD, Meteorological Centre Jaipur, Rajasthan Monsoon Report 2025 and Rajasthan Monsoon Report 2024, both of which use these three normals. A caution on the entry date into Rajasthan: MC Jaipur's own reports describe the 2024 entry on 25 June and the 2025 entry on 18 June as each being "at scheduled normal date", which cannot both be the normal. The station-wise normals in the table above are the citable ones; the state-level entry normal is stated loosely in IMD's own publications and no single figure for it is asserted here.

The last three seasons, as recorded

GovtSources: IMD, Meteorological Centre Jaipur, Rajasthan Monsoon Report 2025 and Rajasthan Monsoon Report 2024, for the 2024 and 2025 rows. For 2026, IMD press releases read in full: 4 June 2026 ("Southwest Monsoon has set in over Kerala, today the 4th June, 2026"); 2 July 2026 ("has further advanced into ... some parts of Rajasthan, today the 02nd July, 2026", with the Northern Limit of Monsoon passing through Neemuch, Tonk, Bhiwani and Bhatinda); 9 July 2026 ("has further advanced into remaining parts of ... Rajasthan, Haryana & Punjab, today the 09th July, 2026. Thus, it has covered the entire country on 09th July, 2026, against the normal date of 08th July"). No IMD Rajasthan Monsoon Report for 2026 exists; the season is not over.

8. Drought

The state's own climate-change plan makes the strongest claim in this chapter about drought, and it is worth quoting rather than paraphrasing: Rajasthan "has the highest probability of drought occurrence in the country."

How drought is measured

Drought is not one thing, and the four kinds are measured differently. The SAPCC 2022 sets out the standard division: meteorological drought, surface water drought, ground water drought and soil-water drought. A meteorological drought is a rainfall deficit; the other three are deficits in what the rain would have produced, and they arrive later and last longer.

For meteorological drought the state's plan uses the Standardised Precipitation Index (SPI), the indicator the World Meteorological Organization recommends to all national meteorological services. SPI expresses rainfall over a chosen window as standard deviations from that window's long-term mean, so it can compare a dry month in Jaisalmer with a dry month in Jhalawar.

GovtSource: Government of Rajasthan, State Action Plan on Climate Change 2022, sections 2.2.5 and 2.3.5, for the SPI thresholds, the four types of drought, and the statement that the state has the highest probability of drought occurrence in the country. The plan's SPI computation uses a gamma distribution fitted to 1981-2010 rainfall. SPI-1, SPI-3, SPI-6 and SPI-12 refer to accumulation windows of one, three, six and twelve months.

IMD measures the same thing differently for operational purposes, as a departure from the long period average. Its categories, as applied in the Rajasthan monsoon reports, are large excess at +60% or more, excess from +20% to +59%, and normal from −19% to +19%, with deficient and scanty below that.

The state's own machinery uses neither index directly. Drought relief in Rajasthan is triggered by the girdawari, the crop-inspection report prepared by the patwari for each village, which records sowing and crop loss on the ground. A district is not declared drought-affected by a rainfall figure; it is declared on a crop assessment, which is why relief notifications name villages and tehsils rather than districts.

The drought-prone districts

A current, dated, official list of Rajasthan's drought-prone districts could not be obtained for this chapter, and none is invented here. What can be stated from sources that were read:

The exposure follows the rainfall gradient exactly. The districts of the Arid Western Plain (I-A) and the Hyper Arid Partially Irrigated Western Plain (I-C) zones of section 5, which are Jodhpur, Phalodi, Barmer, Balotra, Bikaner, Jaisalmer and western Churu, carry annual normals of about 235 to 430 mm and 13 to 26 rainy days a year. Those are the numbers that make a drought, and they are IMD's.

The SAPCC's projection adds a direction. Its analysis finds an increase in drought months across several areas of Rajasthan, most of it in the mild category, and reports research projecting that dry spells will increase in the west and south-west of the state and decrease in the east and centre. The gap between the two halves of Rajasthan is projected to widen, not close.

9. Climate change, as the state itself states it

Rajasthan has a Climate Change Policy, and the date is examinable.

GovtSources: Government of Rajasthan, Directorate of Economics and Statistics, Economic Review 2025-26, chapter 9, "Environmental Sustainability and Climate Resilience", for the policy and its release date; State Action Plan on Climate Change 2022 for the plan itself.

The Economic Review 2025-26 names the state's climate hazards in its own words: "Increasing temperatures, declining groundwater levels, erratic monsoons, frequent droughts, dust storms and emerging heatwave risks." The phrase "emerging heatwave risks" is the state conceding a new hazard, and it is the sentence to quote in a Mains answer.

The SAPCC 2022 carries the findings from the research literature, and they should be attributed as such rather than as the state's own measurements.

• Semi-arid Rajasthan has warmed by about 0.60 °C over the last hundred years (Jonsson et al., 2015, as reported in the plan).
• Warming trends are statistically significant in the north-eastern and western parts of the state, with Sikar's urban areas showing a significant rise in annual daily minimum temperature (Pingale et al., 2014).
• Around 80% of Rajasthan's cities and towns show an average temperature increase of 0.01 to 0.05 °C a year, with the fastest rise, about 0.049 °C a year, at Jhalawar and the slowest, about 0.029 °C a year, at Sirohi (Pingale, 2014).
• Jaipur, Nagaur, Bikaner, Banswara, Jhalawar and Jodhpur are projected to see a significant increase in mean temperature; the higher-elevation districts of Ajmer, Chittorgarh, Bhilwara, Alwar, Udaipur and Sikar are not (Sharma et al., 2018).
• Future precipitation is projected to decrease across the state to 2100, with Banswara showing the largest projected decrease and Alwar, Churu and Sri Ganganagar projected to receive more (Pradhan et al., 2019).

GovtSource: Government of Rajasthan, State Action Plan on Climate Change 2022, chapters 2 and 5. These are findings the plan reports from named studies, not measurements the plan made. They are attributed to their authors here because that is how the plan attributes them, and because a projection from one modelling study is a weaker thing than a departmental figure.

The honest summary is narrower than the headlines. The warming is measured and agreed. The rainfall future is not. One study projects less rain statewide, another finds a positive twentieth-century trend in some grids and no trend elsewhere, and the plan's own conclusion is that the twenty-first-century trend "shows no specific pattern". Write the temperature signal as established and the rainfall signal as contested, and you will be more accurate than most of what is published on this.

Nowadays — what changed in 2026

Covering 1 January to 29 August 2026. Updated every month until Prelims and Mains.

The season was forecast weak, and it has been weak

13 April 2026 — IMD issued its first-stage long range forecast for the 2026 south-west monsoon: 92% of the Long Period Average, with a model error of ±5%.

29 May 2026 — the second-stage forecast revised it down to 90% of LPA, with a model error of ±4%. The all-India LPA on 1971-2020 data is 87 cm. The forecast put an 84% probability on below-normal or less rainfall for the country as a whole, and for North-West India, the homogeneous region Rajasthan belongs to, it made below normal (under 92% of LPA) the most likely of the three categories at 46% probability, against 33% for normal and 21% for above normal. That is a leaning, not a prediction, and it should be quoted with the probability attached.

The driver named is El Nino. IMD stated that neutral ENSO conditions were transitioning towards El Nino over the equatorial Pacific and that El Nino conditions were likely to develop during the monsoon season, with neutral Indian Ocean Dipole conditions expected to continue.

For June 2026 specifically, IMD forecast below-normal heat wave days over Rajasthan, against above-normal heat wave days over much of the Gangetic belt.

GovtSource: PIB, Ministry of Earth Sciences, Updated Long Range Forecast for the Southwest Monsoon Seasonal Rainfall during June-September, 2026 and Monthly Rainfall and Temperature Outlook for June 2026, 29 May 2026, read in full, with Long Range Forecast for the 2026 Southwest Monsoon Season Rainfall, 13 April 2026.

The monsoon reached Rajasthan a week late

4 June 2026 — the south-west monsoon set in over Kerala, three days after the normal date of 1 June.

2 July 2026 — it entered Rajasthan. IMD's release for that day records the advance into "some parts of Rajasthan" with the Northern Limit of Monsoon passing through Neemuch, Tonk, Bhiwani and Bhatinda, so the entry was through the south and south-east, as it always is.

9 July 2026 — it covered the remaining parts of Rajasthan, Haryana and Punjab, and with them the entire country, against the normal date of 8 July.

Set that against the normals. Jhalawar's new normal onset is 24 June and Kota's 26 June; the monsoon reached the Tonk line on 2 July. The 2026 season arrived in Rajasthan about a week behind the station normals for the south-east, and finished only a day behind the state's 8 July coverage normal, having crossed the state in a week.

GovtSources: IMD press releases, read in full: 4 June 2026, 2 July 2026, 9 July 2026.

The last full week of August was dry, and the west had nothing

IMD's Meteorological Centre Jaipur reported the following for the week of 20 to 26 August 2026.

GovtSource: India Meteorological Department, Meteorological Centre Jaipur, Weekly Rainfall Statistics, as on 20/08/2026 to 26/08/2026. This file is republished every week and the figures above are for the week stated, not a season total. Eight of the ten West Rajasthan districts recorded nil rainfall that week — Barmer, Bikaner, Churu, Hanumangarh, Jaisalmer, Jalore, Jodhpur and Sri Ganganagar — with Nagaur at 0.6 mm and Pali at 1.3 mm. In East Rajasthan the same week ran the other way in places, with Bharatpur at +111% and Alwar at +94%.

No IMD seasonal cumulative for Rajasthan in 2026 has been published, because the season is not over: IMD's Rajasthan Monsoon Report is an annual document issued after September, and no 2026 edition exists as of 29 August 2026. Do not carry a 2026 season total for Rajasthan from any source; there is not yet an official one.

What can be said about the season's shape. June opened wet: to 9 June 2026 the state had recorded 19.1 mm against a normal of 7.5 mm, a departure of +154%, before the monsoon had formally arrived, because IMD counts rainfall from 1 June in its monsoon statistics. The last full week of August is the opposite, with West Rajasthan at −99%.August is not over as this is written on 29 August 2026, and the weekly file had not yet rolled forward to the week beginning 27 August. A season that begins in excess and ends in deficit is the ordinary shape of a weak monsoon year, and it is what a 90%-of-LPA forecast describes.

Heat in 2026

The state's highest reading of the 2026 summer reported so far is 48.2 °C at Sri Ganganagar on 27 May 2026, with Bikaner at 46.6 °C, Jaisalmer and Churu at 46.4 °C and Phalodi at 46.2 °C on the same day. These are press reports of IMD readings and not an IMD publication, and they are given as such. Nothing in 2026 has approached the Phalodi record of 51.0 °C, which stands.

What has not changed

The physical geography of the chapter does not move. The Aravalli's alignment, the west-to-east gradient, the 50 cm line, the four seasons and the mechanism of mawath are the same facts they were a decade ago, and no part of section 1, 2 or 3 needs a freshness check beyond the numbers.

The normals have not been revised again. IMD's onset and withdrawal normals are still those published in the 2020 research report, and the station normals are still the 1991-2020 set. A new normal period will arrive with 2001-2030 and has not.

The agro-climatic zones are unchanged: still 10, with the same names and the same district composition as in the Economic Review 2025-26. The Review's district list is already on the current framework, so no correction for the December 2024 reorganisation is needed here.

The Phalodi record of 51.0 °C, 19 May 2016, and the 844.2 mm monsoon of 1917, both still stand.

And Rajasthan still has no published 2026 seasonal rainfall figure, which is stated rather than filled in.

What RPSC has actually asked

Six questions across six Prelims papers carry this chapter's material, and climate has appeared in every paper since 2018. They are worked in full, with RPSC's own keys, on the Geography of Rajasthan PYQ page, under Climate. In summary:

Note what that pattern says about the paper. Two of the questions are the same gradient asked in opposite directions, eight years apart. One is a definition (mawath). One is a mechanism stated in the negative (the Aravalli and rainfall). Only one requires a memorised map, and even that one can be reasoned: Dungarpur is the southernmost and wettest, so it takes the tropical class.

Important for RAS

Prelims Focus

• The Aravalli lies parallel to the Arabian Sea branch of the south-west monsoon, running south-west to north-east in the same direction as the flow, so it produces no orographic lift and no rain. The Bay of Bengal branch reaches Rajasthan already exhausted over the Gangetic plain. Together these explain the west-to-east gradient
• RPSC has confirmed that the Aravalli DOES affect rainfall distribution and DOES restrict the desert's eastward spread (2016, Q35), and that the May and June dust storms are caused by convectional currents, not by the range's alignment (2018, Q28)
• Four seasons in the IMD and NCERT scheme: cold weather, hot weather, south-west monsoon, retreating monsoon. The Rajasthan SAPCC 2022 uses three: hot summer March to June, summer monsoon July to September, cold winter October to February
• January is the coldest month and MAY the hottest by mean daily maximum, at every one of IMD's ten Rajasthan observatories (1991-2020). June carries record highs; May carries the highest normal
• Churu: coldest January mean minimum 5.6 °C, largest annual mean daily range 15.8 K. Kota: smallest range 11.3 K, highest annual mean minimum 21.8 °C
• Seasonal rainfall normals (June to September, IMD 1971-2020): Rajasthan 435.6 mm, East Rajasthan 626.6 mm, West Rajasthan 283.6 mm. Annual average about 572 mm per the state's SAPCC 2022
• Annual station normals (IMD 1991-2020): Jaisalmer 236.9 · Bikaner 285.9 · Barmer 304.4 · Sri Ganganagar 311.9 · Jodhpur 370.2 · Churu 426.2 · Ajmer 571.4 · Jaipur 600.3 · Udaipur (Dabok) 674.2 · Kota 816.2 mm
• Rainy days a year: Jaisalmer 13.1, Kota 38.6
• July is the wettest normal month statewide and in West Rajasthan; August is marginally wetter than July in East Rajasthan
• Monsoon share of annual rainfall: 93% at Udaipur, 92% at Kota, but 76% at Sri Ganganagar and Bikaner. Mawath, winter rain from western disturbances, is a north-western phenomenon
• The 50 cm isohyet divides NCERT's "areas of low rainfall" (50 to 100 cm, eastern Rajasthan) from "areas of inadequate rainfall" (below 50 cm, most of western Rajasthan)
• Koppen types in Rajasthan: Aw, Cwg, BShw, BWhw. D and E do not occur. RPSC's 2021 key accepts Cwg–Bharatpur and Aw–Dungarpur and rejects Bwhw–Barmer and Bshw–Ganganagar
• Ten agro-climatic zones, on the current district framework, from the Economic Review 2025-26. North-western 61% desert or semi-desert, south-eastern 39% fertile
• Highest temperature ever recorded in Rajasthan and in India: 51.0 °C, Phalodi, 19 May 2016. It superseded Alwar's 50.6 °C of 1956. Phalodi was in Jodhpur district at the time and is a separate district now
• Highest monsoon-season rainfall over Rajasthan: 844.2 mm in 1917, with 2025 second at 715.9 mm and 2024 fourth at 678.4 mm
• New normal onset dates (IMD 2020): Jhalawar 24 June, Udaipur 25 June, Kota 26 June, Jaipur 29 June, Ajmer 1 July, Jodhpur 2 July, Churu 4 July, Barmer 5 July, Bikaner and Pokharan 6 July. The monsoon covers the whole state by 8 July, withdrawal begins around 17 September and is complete by 30 September
• The 2020 revision delayed the withdrawal normals by two to three weeks and the onset normals by only a few days
• Drought: the state's SAPCC 2022 states Rajasthan has the highest probability of drought occurrence in the country. Four types: meteorological, surface water, ground water, soil-water. SPI thresholds: mild below −1, severe below −1.5, extreme below −2
• The Rajasthan Climate Change Policy was released on 5 June 2023; the State Action Plan on Climate Change dates from 2022

Interview and Mains Angles

• The Aravalli fails to catch the Arabian Sea branch because of its alignment, and the Bay of Bengal branch reaches Rajasthan spent. Which of the two failures is the state better able to engineer around, and what does the Indira Gandhi canal system's history suggest about the answer?
• Sri Ganganagar and Bikaner take a quarter of their rainfall outside the monsoon, against seven per cent at Udaipur. What does that imply for how a rabi-season contingency plan should differ between the two halves of the state?
• The state's own action plan calls Rajasthan the most drought-prone state in the country and also projects an increase in mild rather than extreme drought months. Is a shift towards frequent mild drought easier or harder to manage than occasional severe drought?
• Four of the ten wettest monsoons since 1901 have fallen since 2011, two of them consecutively in 2024 and 2025, in a state whose infrastructure is built for scarcity. What does an arid state have to build differently once its heavy years become more frequent?
• IMD's withdrawal normals moved two to three weeks later in the 2020 revision while its onset normals barely moved. What follows for cropping calendars, and who bears the cost of a calendar built on the old dates?

Practice

• Practice: Rajasthan's Climate — 45 questions built from this chapter: the Aravalli mechanism, the rainfall gradient, Koppen worked from IMD's normals, the records, and the 2026 season, each with a worked "why not the others".
• Every RAS Prelims Geography question, 2013–2024 — all 78 official questions with RPSC's keys and worked explanations, including the five on climate.

More in This Series

• Rajasthan: Location, Extent and Physiography
• Soils of Rajasthan: Classification, Distribution and Soil Health
• Agriculture of Rajasthan: Crops, Zones and the State's Standing
• Tourism in Rajasthan: Sites, Visitors and the World Heritage Count
• Lakes, Traditional Water Harvesting and Irrigation
• Natural Vegetation, Biodiversity and Conservation
• Livestock and Dairy Development
• Population, Urbanisation and Tribes
• Minerals and Energy Resources
• Caution for Readers — the claims across this site that are genuinely unsettled

Aggregator Watch

Unresolved claims from this box are collected, with what was checked, on the Caution for Readers page.

Sources & Verification

Written on 28 August 2026. Every link below was tested and returned HTTP 200 on that date.

Source priority on this page: the Economic Review 2025-26 for the agro-climatic zones and the state's climate-policy position; IMD for every temperature, rainfall, onset and withdrawal figure; the Government of Rajasthan's State Action Plan on Climate Change 2022 for the state's own account of drought and climate change; NCERT for the national rainfall classes and the monsoon mechanism; and one peer-reviewed paper for the 2016 temperature record. No coaching material or aggregator has been used as a source on this page.

The documents themselves

Taken from the Economic Review 2025-26, read directly: the ten agro-climatic zones with their district composition and crops, the 61% and 39% split of the state, the Rajasthan Climate Change Policy 2023 and its release date of 5 June 2023, and the Review's own list of the state's climate hazards.

Taken from IMD's station files, read directly: all 1991-2020 normals for Ajmer, Barmer, Bikaner, Churu, Jaipur, Jaisalmer, Jodhpur, Kota, Ganganagar and Dabok (Udaipur), covering mean daily maximum and minimum by month, monthly and annual rainfall, rainy days, and thunderstorm and fog day counts. Every station's twelve monthly rainfall values were summed and checked against IMD's own annual total before any figure was used; all ten reconcile to within 0.2 mm. The same check was run on the mean-temperature columns.

Three figures on this page are arithmetic on IMD's data and are labelled as such where they appear: the annual mean daily temperature range (the difference between IMD's two annual columns), the June-to-September share of annual rainfall (the sum of four of IMD's monthly columns over its annual total), and the Koppen classification table in section 4 (Koppen's published thresholds applied to IMD's normals). None of the three is a published figure and none is presented as one.

One IMD document contradicts itself and the contradiction is carried openly. The Rajasthan Monsoon Report 2025 gives the 2025 seasonal total as 715.2 mm in its Highlights and as 715.9 mm in its body text and in Table 2. 715.9 mm is used here because it is the value in the table and in the narrative, and the discrepancy is stated rather than averaged away.

A second internal inconsistency, in IMD's state-level onset normal. The Rajasthan Monsoon Report 2024 describes the monsoon's entry into Rajasthan on 25 June as being "at scheduled normal date"; the 2025 report describes entry on 18 June in the same words. Both cannot be the normal. This page therefore carries the station-wise normals from IMD's 2020 research report and does not assert a single state-level entry date. The three state-level normals that both reports agree on, namely coverage of the state by 8 July, withdrawal beginning around 17 September and complete withdrawal by 30 September, are carried as stated.

Official sources disagree on how many seasons Rajasthan has, and the disagreement is printed rather than resolved. NCERT and IMD give four; the Government of Rajasthan's own SAPCC 2022 gives three and runs winter from October to February; the Rajasthan Foundation gives a fourth arrangement again. They are built for different purposes and no arithmetic reconciles them. The four-fold division is recommended for the exam because it is the one the syllabus vocabulary and the standard textbooks use, not because the others are wrong.

The rank and record claims were checked by trying to refute them, not to confirm them. The Phalodi 51.0 °C record was tested against the 2024 heat wave, which produced Churu at 50.5 °C on 28 May 2024, the highest Indian reading since 2016 and still below the record. The Alwar 1956 figure of 50.6 °C, which preparation material still gives as Rajasthan's highest, is the record Phalodi replaced, and that is stated on the face of the table. The 1917 seasonal rainfall record of 844.2 mm was checked against IMD's own top-ten list for 1901-2025 and stands.

One claim is deliberately not made. Rajasthan's lowest recorded temperature is not given, because no dated figure from a meteorological authority could be reached and the values in circulation conflict with one another. The wettest and driest individual places in the state are likewise not asserted, for the same reason. Both are in Aggregator Watch.

Two 2026 items rest on press reporting rather than on a publication, and are marked where they appear. The 48.2 °C at Sri Ganganagar on 27 May 2026 and the +154% June-to-9-June departure are reports of IMD data rather than IMD documents. The 2026 monsoon dates, by contrast, are from IMD's own press releases, read in full, and the weekly rainfall figures are from IMD's own weekly statistics file.

A caution on the district framework. IMD reports Rajasthan on the thirty-three-district framework, which is why the 2025 monsoon report speaks of "out of total 33 districts". The Economic Review's agro-climatic zone table is on the current framework and names Phalodi, Balotra, Beawar, Deeg, Salumber, Didwana-Kuchaman, Khairthal-Tijara and Kotputli-Behror. A question keyed to an IMD rainfall figure will be on 33 districts; one keyed to an agro-climatic zone will be on 41. Phalodi, where the 2016 temperature record was set, was in Jodhpur district at the time and is a district in its own right now, and RPSC may key either.

Not covered here and therefore not asserted: district-wise rainfall normals, isobar and isotherm patterns over the state, evapotranspiration figures by district, and the detailed synoptic systems of individual seasons. The 2026 season's cumulative rainfall for Rajasthan is not given, because IMD has not published one; its Rajasthan Monsoon Report is an annual document issued after September and no 2026 edition exists.