The short answer: October to mid-December, and March to April. These are the dry, mild months. Days are warm enough for walking, nights are cool, and the rain is low. November is the driest month of the year. If you want cold weather and a chance of snow in the hills, come from late December to February. If you want green hills and quiet roads and don’t mind rain, the monsoon has its own pull, but plan around it carefully.
Dehradun weather by month
These are India Meteorological Department (IMD) averages for Dehradun, from its 1991–2020 climate normals. They describe a typical month, not the week you’re coming. The season and event notes are ours.
| Month | Avg high | Avg low | Rain | Rainy days | Season and crowds | Main events |
|---|---|---|---|---|---|---|
| January | 19.7 °C | 6.6 °C | 43.5 mm | 2.8 | Winter. Coldest month; quiet after New Year. | New Year’s Day (Fri 1 Jan 2027) |
| February | 22.5 °C | 9.2 °C | 57.9 mm | 3.8 | Late winter, warming. Wettest winter month. | — |
| March | 27.4 °C | 13.1 °C | 45.8 mm | 3.2 | Spring. Mild and green. | Jhanda Mela at Darbar Sahib |
| April | 32.5 °C | 17.4 °C | 32.9 mm | 2.7 | Spring into summer. Warm days. | — |
| May | 35.3 °C | 21.2 °C | 51.4 mm | 3.8 | Summer. Hottest month; heavy weekend traffic to the hills. | School holidays, Char Dham season |
| June | 34.1 °C | 23.2 °C | 231.1 mm | 10.3 | Hot, then the monsoon arrives late in the month. | IMA Passing Out Parade; Rajaji safaris end 15 Jun |
| July | 30.6 °C | 23.6 °C | 621.6 mm | 20.5 | Monsoon. Rain most days; road closures possible. | — |
| August | 30.1 °C | 23.1 °C | 714.9 mm | 21.6 | Monsoon. Wettest month of the year. | — |
| September | 30.1 °C | 21.3 °C | 305.9 mm | 12.0 | Monsoon eases; withdraws late in the month. | — |
| October | 29.0 °C | 16.3 °C | 38.3 mm | 2.1 | Autumn. Dry and clear; busy long weekends. | — |
| November | 25.5 °C | 11.4 °C | 5.2 mm | 0.4 | Autumn into winter. Driest month. | Rajaji safaris start 15 Nov |
| December | 21.7 °C | 7.6 °C | 13.0 mm | 1.1 | Winter. Bright days, cold nights; busy last week. | IMA Passing Out Parade; Christmas; Mussoorie Winterline Carnival |
Two numbers tell most of the story. Dehradun gets about 2,160 mm of rain in an average year, and more than three quarters of it falls from June to September. August alone brings about 715 mm over about 22 rainy days. November, by contrast, averages 5 mm and less than one rainy day.
Dates to plan around
- Monsoon
- On IMD’s records the monsoon reaches Dehradun around 28 June on average and withdraws around 26 September. Both dates move a lot: onset has come as early as 10 June and as late as 29 July.IMD: Climate of Dehra Dun, checked 1 Nov 2026
- IMA parade, December 2026
- Expected around Saturday 12 December 2026, not yet announced (as of 1 Nov 2026). The last December parade was on Saturday 13 December 2025.PIB, 13 Dec 2025, checked 1 Nov 2026
- IMA parade, June
- The June 2026 parade was on Saturday 13 June. The June 2027 date is not yet announced.PIB, 13 Jun 2026, checked 1 Nov 2026
- Rajaji safari season
- 15 November to 15 June each year, Garhwal Post reported in October 2025 as the reserve prepared to reopen. We found no 2026 notice from the reserve itself as of 1 Nov 2026; safari operators are giving 15 Nov 2026 as the start.Garhwal Post, 23 Oct 2025, checked 1 Nov 2026
- Mussoorie Winterline Carnival
- 2026 dates not yet announced; the District Magistrate held a preparation review on 29 Oct 2026. Last year it ran 24 to 29 December 2025.Garhwal Post, 30 Oct 2026, checked 1 Nov 2026
- Jhanda Mela
- Begins on the fifth day after Holi. In 2026 it began on Sunday 8 March. It was due to end on 27 March (the Times of India had said 26 March), but the committee extended it for rain and it closed on Sunday 29 March. The 2027 fair is expected in late March, not yet announced.Pioneer Edge, 30 Mar 2026, checked 1 Nov 2026
Our verdict, season by season
Winter (December to February): bright days, cold nights
December days are usually clear and pleasant, around 20 °C, but nights fall to about 7–8 °C, and January is colder still. This is the season for snow trips up to Mussoorie and Dhanaulti, though snow is never guaranteed. Fog is rare here: on IMD’s averages, about one foggy day in December and two in January. The last week of December is one of the busiest on the Mussoorie road. Last year the Dehradun Police issued a special Christmas and New Year traffic plan in mid-December, and barred heavy vehicles from city roads at peak hours from 30 December to 1 January. This winter Christmas falls on Friday 25 December and New Year’s Day on Friday 1 January 2027, so expect two busy weekends in a row.
Our advice: come in the first half of December or after the first week of January for winter without the crowds. Bring a warm jacket for evenings. We’ve written more in Dehradun in winter, Dehradun in December and Dehradun in January.
Spring (March and April): good weather for walking
March warms quickly, from highs around 27 °C to above 32 °C by April, with mild nights. There’s some rain from passing western disturbances, about three rainy days a month. In March the Jhanda Mela at Darbar Sahib brings devotees from Punjab, Haryana, Rajasthan and Uttar Pradesh to the old town, so that part of the city is lively and crowded for a few weeks. If you like Old Dehradun, that’s a good time to see it full of life. If you want it quiet, go in April.
Our advice: early March to mid-April is the pick for long walks and day trips. Do your outdoor plans in the morning by April.
Summer (May and the first half of June): hot here, crowded in the hills
May is the hottest month, with an average high of about 35 °C, and IMD’s Dehradun climate report records heat-wave days in May and June. This is also when the plains empty out towards the hills. In May 2026 the Dehradun Police issued a weekend traffic plan, saying school holidays and the heatwave in Delhi and nearby states were sending people to Mussoorie and Chakrata, with Char Dham and Hemkund Sahib traffic on top. Valley afternoons are warm, but mornings and late evenings stay workable.
Our advice: if summer holidays are your only window, come on weekdays, plan hill trips for early morning, and spend the hot middle of the day indoors. The Rajaji safari season ends on 15 June, so plan a safari before then.
Monsoon (late June to September): green, wet, unpredictable
July and August each average more than 20 rainy days, and heavy rain can close roads at short notice. On 20 July 2026, after a red alert from IMD, the district administration closed the Dehradun–Mussoorie road “till further orders” when part of it sank near Kolhukhet, and advised people to avoid unnecessary travel near rivers, streams and landslide-prone areas. Rivers and seasonal streams rise fast in this season. Stay well away from the water’s edge, and don’t go into rivers or pools at falls.
Our advice: the monsoon suits a slow stay, a good book and a desk more than a list of sights. If you do come, keep your days flexible, check IMD Dehradun’s district warnings every morning before any drive, and read how we check roads and weather.
Autumn (October and November): the clearest weather of the year
Once the monsoon withdraws, the air clears, the hills are still green, and the rain almost stops. October highs are about 29 °C and November about 25 °C. The catch is long weekends. On 3 October 2026, ETV Bharat reported that on weekends and holidays the 35 km drive from Dehradun to Mussoorie was taking visitors close to five hours. On 8 October we told our Instagram followers, “Bring light jackets and enjoy pre winters.”
Our advice: this is the best season for most trips. Avoid holiday weekends for the hill road, and come mid-week if you can. The Rajaji safari season starts on 15 November.
How we’d choose, as people who live here
- For the best weather: mid-October to mid-December. Dry, mild days and the clearest views.
- For a chance of snow nearby: late December to February, and keep a day free after any winter rain in the forecast. We explain why in Dehradun in winter.
- For a family wildlife trip: 15 November to April, inside the Rajaji safari season and before the heat.
- For a cadet’s parade: June or December, and fix your dates as soon as the academy announces them. See our IMA parade guide.
- For a quiet work stay: February, March or the monsoon, when the town is calmer. Fast Wi-Fi and a desk matter more than sights then. See long stays.
- What we’d skip: the Christmas to New Year week and holiday weekends for a first trip to Mussoorie, unless the occasion is the point. Leave room in your day for the road.
Staying with us in any season
Fyonli Nest is our two-bedroom home in Dehradun, with a green room and a red room, each with a king bed. It sleeps 4 adults, or up to 6 guests with children aged 2–12. There are heaters in winter, a courtyard that catches the morning sun, parking in the courtyard and a full kitchen. A pahadi breakfast of mandua roti, aloo and seasonal fruit is ₹350 per guest per morning, on request; tell us the night before. Dogs are welcome if you tell us beforehand. We live ten minutes away and meet you at the gate. See the rooms and send your dates; there’s no payment until we confirm, and cancellation is free until 7 days before arrival.
Sources: IMD climatological table, Dehradun (1991–2020); IMD Meteorological Centre Dehradun: extremes and climatological table; IMD: Climate of Dehra Dun; IMD Meteorological Centre Dehradun: forecasts and warnings; PIB (Dec 2025): 157th Passing Out Parade; PIB (Jun 2026): June 2026 Passing Out Parade; Garhwal Post (Oct 2025): Rajaji reopens 15 Nov; District Dehradun: Mussoorie Winterline Carnival 2025; Garhwal Post (Oct 2026): Winterline Carnival preparations; Times of India (Mar 2026): Jhanda Mela; Pioneer Edge (Mar 2026): Jhanda Mela ends; The Tribune / PTI (May 2026): weekend traffic plan; ETV Bharat (Oct 2026): Dehradun–Mussoorie traffic; Pioneer Edge (Dec 2025): Christmas and New Year traffic plan; Garhwal Post (Jul 2026): Doon–Mussoorie road closed.