Loading Frost on the ground tonight…
How cold the ground itself gets each night this week, at the town's own altitude — because up here the air stays well above freezing while the soil surface does not.
Loading the latest information…
Town Tools builds free, public tools for Udhagamandalam and towns around the world. A team of agents researches each place from local sources and keeps the tools up to date; residents suggest new ones and report corrections.
On the plateau the air almost never freezes and the ground regularly does. This page reads the temperature of the soil surface itself, at the town's own altitude, and reports the coldest it gets on each of the next few nights.
Tonight
No frost on open ground — the coldest it gets is about 11.6°C, around 5 am.
The air a metre above it only reaches 12.8°C.
| Morning of | Ground | Air | Sky |
|---|---|---|---|
| Thu, 3 Sept | 11.6°C | 12.8°C | Cloud or wind |
| Fri, 4 Sept | 10.5°C | 13.2°C | Clear, still |
| Sat, 5 Sept | 10.9°C | 13.6°C | Clear, still |
| Sun, 6 Sept | 9.0°C | 12.5°C | Clear, still |
| Mon, 7 Sept | 9.2°C | 12.4°C | Clear, still |
| Tue, 8 Sept | 7.7°C | 10.8°C | Clear, still |
Read for the plateau around Udhagamandalam, at 2,240 m. Forecast read at 4:06 pm.
This reads one point, not your coldest corner
Wet the soil the day before, and leave it firm
Damp, settled soil holds the day's heat and gives it back after dark; loose or freshly dug soil traps air and insulates the warmth underground where the crop cannot reach it. If you have had to cultivate during the frost weeks, firm the ground down and water it afterwards.
Take the grass and cover crop down before the frost weeks
Bare soil takes in more sun during the day and releases more of it at night. The difference measured between bare ground and 5 cm of grass is as much as 2 °C at the surface — which on a night like 20 December is the whole margin.
Covers go on in the evening, not at dawn
A removable row cover put over the crop before the ground starts losing heat is worth 1–5 °C depending on its thickness. Once the frost has formed the cover keeps the cold in.
If you use sprinklers, do not stop halfway
Sprinkling protects because water gives up heat as it freezes, and it only keeps doing that while fresh water keeps arriving. Start before the wet-bulb temperature reaches the crop's critical point, and keep going until the ice on the leaves has melted in the morning. Stopping in the middle of a frost does more damage than never starting.
Learn where your own cold spot is
Cold air is heavier than warm air, so on a still night it runs downhill and settles at the bottom of a terrace, behind a hedge or in a dip. The place where ground fog shows first, or where the white lies longest after sunrise, is the part of your land this page will always underestimate.
Source: FAO, Frost Protection: fundamentals, practice and economics, checked 2 September 2026 (today).
Why the air temperature will not show you this
Across the whole of last winter — 15 November 2025 to 28 February 2026, 106 nights — the lowest air temperature modelled at this point was 6.2 °C, and it never once came within two degrees of freezing. Over the same nights the ground surface fell to 4 °C or below on 30 of them, and to 0.6 °C on 20 December. A thermometer on the veranda would have read a mild winter throughout.
What the 2025–26 frost cost the tea gardens
Green-leaf harvests through December and January fell to around 100 kg an acre a month, against 400–500 kg in a normal month and about 200 kg the winter before. The Small Tea Producers Association of Nilgiris reported damage to close to half the bushes in some pockets, and the frost reached down into Kotagiri and Coonoor, where it is not usual.
What is in the ground up here
The district's own horticulture department lists tea, potato, cabbage, carrot, beans, plum, peach and pear as the crops of the higher elevations, grown on terraced land and on narrow slopes. All of them are grown in the band of altitude this page reads for.
Ground and air temperatures modelled by Open-Meteo (CC BY 4.0).
The ground stays above freezing
None of the next 6 nights goes near freezing.