Iowa

Pomeroy, Iowa Climate

NOAA 1991-2020 normals for Rockwell City, 17.7 km from Pomeroy

The warmest month is July, with an average high of 83°F; the coldest is January, with an average low of 8°F. A normal year brings 33.8 in of precipitation and 32.1 in of snow.

Temperature through the year

The normal daily high and low and the record for every date at Fort Dodge (FOD), since 1899. The line marks today.

Normal daily high and low temperature at Pomeroy 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
73°F
Normal low
48°F
Record high
89°Fin 1935
Record low
28°Fin 1942
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
January27°F8°F66°F (1944)-35°F (1912)0.76 in5.37.4 in30.51,4740
February31°F12°F75°F (2024)-30°F (1996)0.99 in5.27.6 in26.91,2080
March45°F24°F90°F (2026)-22°F (1962)1.99 in7.04.9 in23.89380
April59°F36°F100°F (1980)6°F (1975)3.76 in9.41.9 in10.45324
May70°F49°F106°F (1934)21°F (1907)5.02 in12.40.0 in0.821843
June80°F60°F104°F (1934)34°F (1945)5.04 in10.90.0 in0.030166
July83°F63°F110°F (1936)42°F (1934)3.54 in8.80.0 in0.06250
August81°F61°F109°F (1936)35°F (1915)4.53 in8.80.0 in0.015188
September75°F51°F103°F (1939)20°F (1942)2.95 in7.80.0 in0.213173
October62°F38°F95°F (1997)-4°F (1925)2.35 in8.10.6 in8.14648
November46°F25°F87°F (2005)-9°F (1977)1.48 in5.02.4 in23.18820
December32°F15°F69°F (2021)-26°F (1983)1.34 in5.47.3 in29.91,2900
Year58°F37°F33.75 in9432.1 in1547,187733

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.

33.8 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 Pomeroy, in percent, and of at least 0.1 inch of snowfall.010203040JanFebMarAprMayJunJulAugSepOctNovDec
  • Chance of a wet day
  • Chance of snowfall

Snow

NOAA 1991-2020 snowfall normals for Rockwell City.

32.1 in of snow in a normal year.

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Rockwell City. 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 26 and the first fall freeze around October 10, a growing season of about 167 days.

Median at 36°F
last May 4, first October 1
Median at 32°F
last April 26, first October 10
Median at 28°F
last April 16, first October 21

Frost dates, growing season and degree days

Humidity and comfort

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

The muggiest month is July, when 42 percent of days are muggy or worse, with a mean dew point of 65°F or more.

MonthDew pointHumidityDryComfortableHumidMuggyOppressiveMiserable
January14°F86%100%0%0%0%0%0%
February18°F82%100%0%0%0%0%0%
March28°F75%99%1%0%0%0%0%
April38°F70%96%4%1%0%0%0%
May50°F71%69%15%10%5%0%0%
June60°F72%27%24%20%20%9%1%
July63°F69%14%21%24%25%15%2%
August60°F68%25%25%24%17%9%1%
September51°F67%64%16%11%6%3%0%
October39°F70%92%5%2%1%0%0%
November28°F77%99%1%0%0%0%0%
December19°F85%100%0%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 49 percent covered on average; the cloudiest is March, at 65 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 April, averaging 13.2 mph at 10 meters (33 feet) above the ground.

Daylight and sunshine

The longest day is Jun 19, with 15 h 19 min of daylight; the shortest is Dec 18, with 9 h 03 min.

Hours of daylight at Pomeroy 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 Calhoun 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 Calhoun County: 71.4°F (+0.9 °F against 1991-2020), the 55th warmest in 132 years on record.

August 2026 in Calhoun County: 4.47 in (+0.24 in against 1991-2020), the 40th wettest in 132 years on record.

January to August 2026 in Calhoun County: 52.9°F (+3.1 °F against 1991-2020), the 5th warmest in 132 years on record.

January to August 2026 in Calhoun County: 19.24 in (-5.94 in against 1991-2020), the 34th driest in 132 years on record.

Warmest August
79.2°F in 1947
Coolest August
64.6°F in 1915
Wettest August
14.07 in in 2007
Driest August
0.55 in in 1909

Every year since 1895

Each year's average temperature in Calhoun County against the 1991-2020 average, in °F, 1895 to 2025.-6-4-20+2+4+61900192019401960198020002020NOAA NCEI Climate at a Glance

Iowa climate and rankings

Month pages

The weather in Pomeroy 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 1899. 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 USC00137161 (Rockwell City), public domain. Records: NOAA GHCN-Daily, station USC00132999, 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.