Ratchaburi

Ban I Chang, Thailand Climate

NASA POWER reanalysis for the half-degree grid cell around Ban I Chang, 1991-2020; a grid cell is an area average and can differ from a thermometer in town by several degrees

The warmest month is April, with an average high of 36°C; the coldest is December, with an average low of 20°C. A normal year brings 1125 mm of precipitation.

Temperature through the year

The normal daily high and low. The line marks today.

Normal daily high and low temperature at Ban I Chang through the year, in °C, with the record for each date.01020304050JanFebMarAprMayJunJulAugSepOctNovDec
  • Normal low
  • Normal high
  • Reanalysis extreme high
  • Reanalysis extreme low

Normals for Sep 26

Normal high
30°C
Normal low
25°C
Reanalysis high
33°Cin 2015
Reanalysis low
24°Cin 2013
Chance of a wet day
87%
Daylight
12 h 04 min

Month by month

Averages for 1991-2020. Wet days have at least 1 mm of precipitation in the reanalysis. Each month links to its own page.

MonthAvg highAvg lowWarmestColdestPrecipitationWet days
January32°C21°C36°C (2005)13°C (2009)16 mm3.1
February34°C23°C39°C (1998)15°C (2016)11 mm2.8
March36°C25°C40°C (2016)16°C (2011)40 mm6.2
April36°C26°C42°C (2016)19°C (2018)60 mm9.0
May34°C26°C41°C (1998)24°C (2007)133 mm21.7
June33°C26°C40°C (1992)23°C (2004)120 mm21.0
July32°C25°C38°C (2015)23°C (2009)121 mm21.7
August32°C25°C37°C (2016)23°C (2006)121 mm21.7
September31°C25°C35°C (2015)22°C (2008)210 mm24.0
October30°C24°C34°C (2004)17°C (1994)233 mm24.8
November30°C22°C36°C (2004)15°C (2007)51 mm9.0
December30°C20°C35°C (2019)9°C (1999)9 mm3.1
Year32°C24°C1125 mm168

Precipitation

Rain and melted snow together. The chance of a wet day is the share of days with at least 1 mm of precipitation in the reanalysis.

1125 mm in a normal year, most in October.

Chance of a wet day

The chance of at least 1 mm of precipitation in the reanalysis on each date at Ban I Chang, in percent.020406080100JanFebMarAprMayJunJulAugSepOctNovDec
  • Chance of a wet day

Humidity and comfort

NASA POWER reanalysis, 1991-2020, for the grid cell around Ban I Chang.

The muggiest month is May, when 100 percent of days are muggy or worse, with a mean dew point of 18°C or more.

MonthDew pointHumidityDryComfortableHumidMuggyOppressiveMiserable
January19°C66%5%11%26%38%21%0%
February19°C63%3%9%17%41%30%0%
March21°C63%0%2%7%36%53%2%
April22°C65%0%0%2%14%72%12%
May24°C73%0%0%0%2%48%50%
June24°C76%0%0%0%1%48%51%
July23°C77%0%0%0%0%70%30%
August23°C77%0%0%0%0%73%27%
September24°C82%0%0%0%0%49%51%
October24°C84%0%0%0%3%39%58%
November22°C80%0%1%6%23%53%17%
December19°C71%3%12%22%37%25%1%

Comfort is judged by the day's mean dew point: dry below 13°C, comfortable to 16°C, humid to 18°C, muggy to 21°C, oppressive to 24°C, miserable above.

Clouds

Average share of the sky covered, from satellite (CERES and GEWEX SRB) by way of NASA POWER, 1991-2020.

The clearest month is February, with the sky 36 percent covered on average; the cloudiest is August, at 91 percent.

Wind

The mean wind speed over the whole day, from the MERRA-2 reanalysis by way of NASA POWER. Gusts run well above it.

The windiest month is March, averaging 12.6 km/h at 10 meters (33 feet) above the ground.

Daylight and sunshine

The longest day is Jun 22, with 12 h 57 min of daylight; the shortest is Dec 15, with 11 h 19 min.

Hours of daylight at Ban I Chang through the year.0510152025JanFebMarAprMayJunJulAugSepOctNovDec
  • Day length

Solar energy

Average daily sunshine reaching the ground on a flat surface, in kilowatt-hours per square meter, clouds included.

Sunrise and sunset calendar

Month pages

The weather in Ban I Chang in each month, day by day.

What this means

A normal is the average of the thirty years 1991 to 2020, the period the World Meteorological Organization and NOAA use for comparison. It is an average, not a forecast: most days depart from it, and some by a long way.

Where no station record is within reach, the extremes shown are the highest and lowest the reanalysis produced for the date in 1991-2020, not measured records.

Cloud, humidity, wind and sunshine come from a reanalysis: a weather model run over the past with every observation fed in, averaged over a grid cell about 50 km across. It is consistent everywhere on Earth; it smooths local detail such as a lake shore or a valley.

More for this place

Nearby

Sources

Cloud, humidity, wind and sunshine, and temperature and precipitation: NASA POWER (MERRA-2, CERES and GEWEX SRB), 1991-2020. The data was obtained from the National Aeronautics and Space Administration (NASA) Langley Research Center's Prediction Of Worldwide Energy Resources (POWER) project funded through the NASA Earth Science Division: POWER Daily API v2, accessed 2026-09-24. Sun and moon: computed with the NOAA solar equations and Meeus.