Kota air pressure: how barometric pressure changes through the year

Kota air pressure rarely makes headlines, but it quietly shapes the city’s seasons. High pressure in winter brings settled, clear, dry weather; low pressure in early summer and the monsoon goes with heat, wind and rain. If you own a barometer, use a weather station at home, or are simply puzzled why different sources give different pressure values for Kota, this guide explains the official figures.

The numbers come from the India Meteorological Department’s (IMD) Climatological Tables 1991-2020 for Kota (station 42452), which give the mean station-level pressure at 08:30 IST (03 UTC) and 17:30 IST (12 UTC). They are long-term averages, not a forecast.

Kota air pressure by month

Month	08:30 IST	17:30 IST	Morning to evening
January	986.1 hPa	983.1 hPa	-3.0
February	984.1 hPa	980.9 hPa	-3.2
March	981.5 hPa	977.8 hPa	-3.7
April	978.0 hPa	973.8 hPa	-4.2
May	974.1 hPa	969.9 hPa	-4.2
June	970.5 hPa	966.6 hPa	-3.9
July	969.7 hPa	966.7 hPa	-3.0
August	971.8 hPa	969.1 hPa	-2.7
September	975.9 hPa	972.6 hPa	-3.3
October	981.1 hPa	977.8 hPa	-3.3
November	984.6 hPa	981.4 hPa	-3.2
December	986.2 hPa	983.2 hPa	-3.0
Year	978.5 hPa	975.2 hPa	-3.3

hPa (hectopascal) is the same unit as the millibar (mb).

The yearly cycle: high in winter, low in the monsoon

Kota’s pressure follows a clear seasonal curve. It is highest in December and January, about 986 hPa in the morning, when cold, dense air settles over north India and skies are clear. From February it falls steadily as the land heats up. By May and June the hot plains of northwest India and Pakistan sit under a broad seasonal low, and Kota’s pressure drops to around 970 hPa in the morning and under 967 hPa in the evening. The lowest values come in June and July, when this heat low and the monsoon trough draw moist air in from the Arabian Sea and the Bay of Bengal. After the monsoon withdraws in September and October, pressure rises again.

The difference between the winter peak and the monsoon low is about 16 hPa. That swing is part of the same large-scale pattern that drives the monsoon itself. Read more in our Kota monsoon guide.

The daily cycle: falling from morning to evening

In every month, the 17:30 reading is about 3 to 4 hPa lower than the 08:30 reading. In the tropics, pressure rises and falls twice a day in a regular pattern, with highs around mid-morning and late evening and lows in the afternoon and early morning. Strong daytime heating adds to the afternoon fall, which is why the morning-to-evening drop is largest in April and May (4.2 hPa) and smallest in the cloudy monsoon month of August (2.7 hPa).

This matters if you are reading a home barometer. A drop of 3 hPa between breakfast and evening is normal in Kota and does not by itself mean a storm is coming.

Station pressure vs sea level pressure

IMD’s table gives station-level pressure: the weight of the air above the barometer at the observatory. Weather maps, forecasts and most apps show mean sea level pressure, which is the station reading adjusted to what it would be at sea level, so that places at different heights can be compared. Because the Kota observatory is above sea level, its station pressure is lower than the sea-level value you see in apps, which is why app values for Kota are usually above 1000 hPa. Both are correct; they answer different questions.

If you set a home barometer or an altimeter watch, check which value it expects. Barometers on forecast maps are normally set to sea level pressure, while some instruments record raw station pressure.

Pressure and Kota’s weather

• Winter highs: settled high pressure brings calm, clear nights, cool mornings and, on some days, fog or haze. See Kota winter weather and Kota fog.
• Western disturbances: in winter and spring, a passing low brings a fall in pressure, cloud, sometimes rain, thunder or hail, and then a cooler spell. See Kota thunderstorms.
• Summer low: falling pressure over the heated plains goes with hot westerly winds and dust storms from April to June. See Kota wind and Kota dust storm.
• Monsoon systems: low-pressure areas and depressions moving across central India can bring several days of heavy rain to Hadoti. IMD tracks them in its bulletins. See Kota rainfall.

Reading a home barometer in Kota

If you keep a barometer or a home weather station, a few simple habits make its readings useful:

1. Note the setting. Find out whether the display shows station pressure or a sea-level value. Many home stations let you enter your altitude so they can show a sea-level figure comparable with forecasts.
2. Compare at the same hour. Because pressure falls by 3 to 4 hPa from morning to evening, compare today’s 08:30 reading with the 08:30 normal for the month, not with an evening value.
3. Watch the trend over a day or two. In winter, a steady fall followed by a rise often brackets the passage of a western disturbance. In the monsoon, falls are part of the season’s normal pattern and are better read alongside IMD bulletins.
4. Do not over-read small changes. A change of 1 to 2 hPa within a few hours is ordinary in Kota.

Pressure and humidity in the same table

IMD’s tables also list the mean vapour pressure, the part of the air pressure made up by water vapour. At Kota it climbs from about 9 to 11 hPa between January and April to around 28 to 30 hPa in July and August. That rise is the moisture of the monsoon arriving, and it is why the monsoon feels so much heavier than the dry heat of May. Our Kota humidity guide explains the relative humidity figures that go with it.

Does pressure affect how you feel?

Some people say they feel weather changes in their joints or as headaches, and pressure falls are sometimes blamed. Kota’s normal changes are gradual, a few hPa a day. In practice, heat, humidity, dust and air quality affect health in Kota far more than pressure does. Our Kota heatwave and Kota air quality guides cover those risks.

Where the numbers come from

The observatory and its full list of measurements are explained in our Kota weather station guide. For the rest of Kota’s monthly averages, see Kota weather by month.