Climate in Patna (Bihar)

The climate of Patna is subtropical, with a rainy season that runs roughly from mid-June to early October, due to the monsoon, and a dry season from mid-October to early June.
The city is located in northeastern India, in the state of Bihar (of which it is the capital), at 25 degrees north latitude and on the banks of the Ganges.
We are in the Indo-Gangetic plain, which is a very polluted area, especially from October to February, when air stagnates more easily.
In winter, from mid-November to late February or early March, nights are cool, and sometimes even cold. In January 2013, the temperature dropped to 1 °C (34 °F).
In addition, from November to January, fog can form at night and in the early morning. The fog usually dissolves during the day, however, in these situations, it can sometimes be cool even during the day, with highs of 15/16 °C (59/61 °F), and sometimes even below.
From mid-March to mid-June, before the monsoon, it is very hot. In the hottest periods, the temperature can reach or exceed 45 °C (113 °F).



Patna is in the path of tropical cyclones, which come from the Bay of Bengal, usually from mid-April to early December. In general, they are most intense either at the beginning and the end of the period, that is, in May-June and October-November. Since we are far from the coast, the city is not hit by cyclones at full strength, however, they can bring heavy rainfall, as happened for example at the end of May 2021 with cyclone Yaas.

Best Time

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The best time to visit Patna is from mid-November to mid-February, being the coolest within the dry season. It must be said that this is the time of the year when pollution is highest. Also, in the middle of winter, usually from mid-December to mid-January, it can get a little cold and fog can be persistent, so the latter period can be avoided.

Patna - Climate data

In Patna, the average temperature of the coldest month (January) is of 15.4 °C (59.6 °F), that of the warmest month (June) is of 31.7 °C (89.1 °F). Here are the average temperatures.
Precipitation amounts to 1145 millimeters (45.1 inches) per year: it is therefore quite abundant. It ranges from 6.1 mm (0.2 in) in the driest month (December) to 355 mm (14 in) in the wettest one (July). Here is the average precipitation.
There are on average around 2550 sunshine hours per year. Here are the average hours of sunshine per day.

Patna - Weather by month

Based on the period 1991-2020

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January, the coldest month of the year, is generally a very mild month. The average temperature is of 15.4 °C (60 °F), with a minimum of 9 °C (48.3 °F) and a maximum of 21.7 °C (71 °F).
On the coldest nights of the month, the temperature usually drops to around 4.5 °C (40.5 °F).
On the warmest days of the month, the temperature usually reaches around 26.5 °C (80 °F).
Precipitation amounts to 11.1 mm (0.4 in), and all occurs in one day.
The day lasts on average 10 hours and 50 minutes.
There are on average 6.5 hours of sunshine per day. So, the sun shines 62% of the time.
The average humidity is 75%. Hence, the air is normally humid.
The average wind speed is 4 kph (2 mph).

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February is generally a warm month. However, there are remarkable differences between night and day. The average temperature is of 19.5 °C (67 °F), with a minimum of 12.5 °C (54.5 °F) and a maximum of 26.6 °C (79.8 °F).
On the coldest nights of the month, the temperature usually drops to around 8 °C (46.5 °F).
On the warmest days of the month, the temperature usually reaches around 31 °C (88 °F).
Precipitation amounts to 14 mm (0.6 in), and all occurs in one day.
The day lasts on average 11 hours and 20 minutes.
There are on average 8 hours of sunshine per day. So, the sun shines 72% of the time.
The average humidity is 64%.
The average wind speed is 5 kph (3 mph).

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March is generally a warm to hot month. However, there are remarkable differences between night and day. The average temperature is of 24.9 °C (77 °F), with a minimum of 17.2 °C (63 °F) and a maximum of 32.5 °C (90.5 °F).
On the coldest nights, which normally occur at the beginning of the month, the temperature usually drops to around 12 °C (54 °F).
On the warmest days, which normally occur at the end of the month, the temperature usually reaches around 38 °C (100 °F).
Precipitation amounts to only 9.5 mm (0.4 in), and all occurs in one day.
The day lasts on average 12 hours and 0 minutes.
There are on average 8.5 hours of sunshine per day. So, the sun shines 70% of the time.
The average humidity is 50%.
The average wind speed is 6 kph (4 mph).

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April is generally a very hot month. However, there are remarkable differences between night and day. The average temperature is of 29.6 °C (85 °F), with a minimum of 22.2 °C (71.9 °F) and a maximum of 36.9 °C (98.5 °F).
On the coldest nights, which normally occur at the beginning of the month, the temperature usually drops to around 18 °C (64 °F).
On the warmest days, which normally occur at the end of the month, the temperature usually reaches around 41 °C (106 °F).
Precipitation amounts to 12.7 mm (0.5 in), and all occurs in one day.
The day lasts on average 12 hours and 50 minutes.
There are on average 9 hours of sunshine per day. So, the sun shines 69% of the time.
The average humidity is 45%.
The average wind speed is 8 kph (5 mph).

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May is generally a very hot month. The average temperature is of 31.5 °C (89 °F), with a minimum of 25.2 °C (77.3 °F) and a maximum of 37.8 °C (100.1 °F).
On the coldest nights, which normally occur at the beginning of the month, the temperature usually drops to around 20.5 °C (69.5 °F).
On the warmest days, which normally occur at the end of the month, the temperature usually reaches around 43 °C (109.5 °F).
Precipitation amounts to 45 mm (1.8 in), distributed over 3 days.
The day lasts on average 13 hours and 25 minutes.
There are on average 9 hours of sunshine per day. So, the sun shines 66% of the time.
The average humidity is 54%.
The average wind speed is 10 kph (6 mph).

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June, the hottest month of the year, is generally a very hot month. The average temperature is of 31.7 °C (89 °F), with a minimum of 26.8 °C (80.3 °F) and a maximum of 36.7 °C (98 °F).
On the coldest nights, the temperature usually drops to around 23 °C (73.5 °F).
On the warmest days, the temperature usually reaches around 42 °C (107.5 °F).
Precipitation amounts to 165 mm (6.5 in), distributed over 7 days.
The day lasts on average 13 hours and 40 minutes. June 21, the summer solstice, is the longest day of the year in the Northern Hemisphere.
There are on average 6.5 hours of sunshine per day. So, the sun shines 47% of the time.
The average humidity is 66%.
The average wind speed is 9 kph (6 mph).

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July is generally a very hot, muggy month. The average temperature is of 30 °C (86 °F), with a minimum of 26.5 °C (79.6 °F) and a maximum of 33.5 °C (92.3 °F).
On the coldest nights of the month, the temperature usually drops to around 24 °C (75 °F).
On the warmest days of the month, the temperature usually reaches around 37.5 °C (99 °F).
Precipitation amounts to 355 mm (14 in), distributed over 14 days.
The day lasts on average 13 hours and 30 minutes.
There are on average 4 hours of sunshine per day. So, the sun shines 31% of the time.
The average humidity is 79%. Hence, the air is normally humid.
The average wind speed is 8 kph (5 mph).

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August is generally a very hot, muggy month. The average temperature is of 29.8 °C (86 °F), with a minimum of 26.4 °C (79.4 °F) and a maximum of 33.2 °C (91.8 °F).
On the coldest nights of the month, the temperature usually drops to around 23.5 °C (74.5 °F).
On the warmest days of the month, the temperature usually reaches around 36.5 °C (98 °F).
Precipitation amounts to 280 mm (11 in), distributed over 12 days.
The day lasts on average 13 hours and 0 minutes.
There are on average 5 hours of sunshine per day. So, the sun shines 38% of the time.
The average humidity is 81%. Hence, the air is normally humid.
The average wind speed is 8 kph (5 mph).

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September is generally a very hot, muggy month. The average temperature is of 29.2 °C (85 °F), with a minimum of 25.6 °C (78 °F) and a maximum of 32.9 °C (91.2 °F).
On the coldest nights, the temperature usually drops to around 23 °C (73.5 °F).
On the warmest days, the temperature usually reaches around 36 °C (96.5 °F).
Precipitation amounts to 200 mm (7.9 in), distributed over 10 days.
The day lasts on average 12 hours and 20 minutes.
There are on average 5.5 hours of sunshine per day. So, the sun shines 44% of the time.
The average humidity is 80%. Hence, the air is normally humid.
The average wind speed is 7 kph (4 mph).

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October is generally a warm to hot, muggy month. The average temperature is of 27.1 °C (81 °F), with a minimum of 22 °C (71.5 °F) and a maximum of 32.2 °C (89.9 °F).
On the coldest nights, which normally occur at the end of the month, the temperature usually drops to around 17 °C (62.5 °F).
On the warmest days, which normally occur at the beginning of the month, the temperature usually reaches around 35.5 °C (96 °F).
Precipitation amounts to 50 mm (2 in), distributed over 3 days.
The day lasts on average 11 hours and 30 minutes.
There are on average 7.5 hours of sunshine per day. So, the sun shines 67% of the time.
The average humidity is 74%. Hence, the air is normally humid.
The average wind speed is 3 kph (2 mph).

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November is generally a warm month. However, there are remarkable differences between night and day. The average temperature is of 22.3 °C (72 °F), with a minimum of 15.6 °C (60 °F) and a maximum of 29 °C (84.2 °F).
On the coldest nights, which normally occur at the end of the month, the temperature usually drops to around 11 °C (51.5 °F).
On the warmest days, which normally occur at the beginning of the month, the temperature usually reaches around 32 °C (90 °F).
Precipitation amounts to only 7.2 mm (0.3 in), distributed over 0 days.
The day lasts on average 10 hours and 55 minutes.
There are on average 8 hours of sunshine per day. So, the sun shines 73% of the time.
The average humidity is 69%.
The average wind speed is 2 kph (1 mph).

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December is generally a very mild month. However, there are remarkable differences between night and day. The average temperature is of 17.2 °C (63 °F), with a minimum of 10.5 °C (50.9 °F) and a maximum of 23.8 °C (74.9 °F).
On the coldest nights of the month, the temperature usually drops to around 6.5 °C (43.5 °F).
On the warmest days of the month, the temperature usually reaches around 28 °C (82.5 °F).
Precipitation amounts to only 6.1 mm (0.2 in), and all occurs in one day.
The day lasts on average 10 hours and 35 minutes. December 21, the winter solstice, is the shortest day of the year in the Northern Hemisphere.
There are on average 6.5 hours of sunshine per day. So, the sun shines 61% of the time.
The average humidity is 74%. Hence, the air is normally humid.
The average wind speed is 2 kph (1 mph).