Indiana

Putnam County, Indiana Climate

NOAA 1991-2020 normals for Greencastle 1 W, 3.7 km from Putnam County

The warmest month is July, with an average high of 83°F; the coldest is January, with an average low of 17°F. A normal year brings 46.1 in of precipitation and 22.1 in of snow.

Temperature through the year

The normal daily high and low and the record for every date at Greencastle (GPC), since 1895. The line marks today.

Normal daily high and low temperature at Putnam County through the year, in °F, with the record for each date.-50050100150JanFebMarAprMayJunJulAugSepOctNovDec
  • Normal low
  • Normal high
  • Record high
  • Record low

Normals for Sep 24

Normal high
74°F
Normal low
49°F
Record high
92°Fin 1920
Record low
31°Fin 1928
Chance of a wet day
26%
Daylight
12 h 04 min

Month by month

Averages for 1991-2020. Wet days have at least 0.01 inch of precipitation. Freeze nights have a low of 32°F or colder; degree days are on a 65°F base. Each month links to its own page.

MonthAvg highAvg lowRecord highRecord lowPrecipitationWet daysSnowfallFreeze nightsHeating DDCooling DD
January34°F17°F71°F (1950)-23°F (1985)3.18 in10.79.3 in26.71,2200
February39°F20°F74°F (1932)-20°F (1951)2.63 in9.14.3 in23.59950
March50°F29°F86°F (1929)-8°F (1943)3.50 in10.82.2 in20.07931
April62°F39°F90°F (1930)16°F (1982)4.65 in11.60.1 in6.44466
May72°F49°F95°F (1919)28°F (1947)4.91 in12.50.0 in0.718850
June80°F58°F105°F (1954)34°F (2003)5.36 in11.40.0 in0.034162
July83°F61°F108°F (1936)41°F (1929)4.72 in9.80.0 in0.07230
August82°F59°F105°F (1918)40°F (1965)3.36 in8.60.0 in0.012192
September77°F52°F106°F (1954)26°F (1928)3.67 in7.60.0 in0.29881
October65°F41°F95°F (1919)18°F (1925)3.59 in8.10.1 in4.938911
November51°F30°F85°F (1950)-6°F (1950)3.61 in9.80.9 in16.47320
December39°F22°F74°F (1982)-21°F (1989)2.96 in11.55.2 in25.01,0600
Year61°F40°F46.14 in12122.1 in1245,973733

Precipitation

Rain and melted snow together. The chance of a wet day is the share of days with at least 0.01 inch of precipitation.

46.1 in in a normal year, most in June.

Chance of a wet day

The chance of at least 0.01 inch of precipitation on each date at Putnam County, in percent, and of at least 0.1 inch of snowfall.01020304050JanFebMarAprMayJunJulAugSepOctNovDec
  • Chance of a wet day
  • Chance of snowfall

Snow

NOAA 1991-2020 snowfall normals for Greencastle 1 W.

22.1 in of snow in a normal year.

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Greencastle 1 W. A median date has an even chance of a later freeze in spring, or an earlier one in fall.

The last spring freeze typically comes around April 27 and the first fall freeze around October 15, a growing season of about 169 days.

Median at 36°F
last May 8, first October 4
Median at 32°F
last April 27, first October 15
Median at 28°F
last April 15, first October 26

Frost dates, growing season and degree days

Humidity and comfort

NASA POWER reanalysis, 1991-2020, for the grid cell around Putnam County.

The muggiest month is July, when 62 percent of days are muggy or worse, with a mean dew point of 65°F or more.

MonthDew pointHumidityDryComfortableHumidMuggyOppressiveMiserable
January24°F86%99%1%0%0%0%0%
February27°F84%99%1%0%0%0%0%
March35°F81%93%4%2%0%0%0%
April45°F78%79%12%7%2%0%0%
May56°F79%46%16%17%19%3%0%
June64°F79%12%16%22%27%21%2%
July66°F77%5%13%21%27%30%5%
August64°F73%10%22%23%25%19%1%
September55°F69%48%19%16%13%4%0%
October45°F73%82%10%5%3%0%0%
November35°F79%96%4%1%0%0%0%
December28°F85%99%1%0%0%0%0%

Comfort is judged by the day's mean dew point: dry below 55°F, comfortable to 60°F, humid to 65°F, muggy to 70°F, oppressive to 75°F, 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 September, with the sky 48 percent covered on average; the cloudiest is December, at 71 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 January, averaging 10.3 mph at 10 meters (33 feet) above the ground.

Daylight and sunshine

The longest day is Jun 17, with 14 h 59 min of daylight; the shortest is Dec 17, with 9 h 22 min.

Hours of daylight at Putnam County 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

How Putnam County is running

NOAA NCEI Climate at a Glance, from the nClimGrid analysis of every station, updated early each month. A rank of 1 is the highest or lowest of all years since 1895.

August 2026 in Putnam County: 72.6°F (+0.7 °F against 1991-2020), the 57th warmest in 132 years on record.

August 2026 in Putnam County: 6.67 in (+3.35 in against 1991-2020), the 8th wettest in 132 years on record.

January to August 2026 in Putnam County: 55.0°F (+1.4 °F against 1991-2020), the 19th warmest in 132 years on record.

January to August 2026 in Putnam County: 36.08 in (+4.68 in against 1991-2020), the 11th wettest in 132 years on record.

Warmest August
78.8°F in 1936
Coolest August
66.0°F in 1915
Wettest August
9.38 in in 1979
Driest August
0.78 in in 2010

Every year since 1895

Each year's average temperature in Putnam County against the 1991-2020 average, in °F, 1895 to 2025.-4-20+2+41900192019401960198020002020NOAA NCEI Climate at a Glance

Indiana climate and rankings

Month pages

The weather in Putnam County 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.

A record is the highest or lowest value on the date in every year the station has reported, back to 1895. It rests on one station, so a neighbor a few miles away can hold different ones.

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

Normals: NOAA NCEI U.S. Climate Normals, 1991-2020, station USC00123513 (Greencastle 1 W), public domain. Records: NOAA GHCN-Daily, station USC00123513, every year on file, quality-flagged values removed. Cloud, humidity, wind and sunshine: 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. Rankings: NOAA NCEI Climate at a Glance, public domain.