Iowa

Underwood, Iowa Climate

NOAA 1991-2020 normals for Omaha Eppley Airfield, 20.4 km from Underwood

The warmest month is July, with an average high of 88°F; the coldest is January, with an average low of 15°F. A normal year brings 31.9 in of precipitation and 27.1 in of snow.

Temperature through the year

The normal daily high and low and the record for every date at Council Bluffs (CBF), since 1948. The line marks today.

Normal daily high and low temperature at Underwood 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
76°F
Normal low
53°F
Record high
89°Fin 2017
Record low
31°Fin 1965
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°F15°F69°F (2012)-23°F (1982)0.75 in6.97.2 in29.71,2580
February39°F19°F80°F (2024)-23°F (2021)0.95 in7.37.8 in25.61,0090
March52°F30°F96°F (2026)-16°F (1948)1.79 in8.03.0 in19.97452
April64°F41°F97°F (1989)5°F (1975)3.17 in10.51.0 in6.338614
May75°F53°F101°F (2013)27°F (1976)4.66 in12.80.1 in0.313290
June84°F63°F105°F (2021)38°F (1983)4.44 in11.00.0 in0.011278
July88°F68°F110°F (1974)44°F (1972)3.55 in9.90.0 in0.01405
August86°F66°F107°F (1964)43°F (1950)4.60 in8.90.0 in0.03335
September79°F56°F103°F (1975)25°F (1984)2.96 in7.80.0 in0.171148
October66°F43°F96°F (2024)13°F (1972)2.32 in7.20.5 in4.435121
November50°F30°F83°F (1999)-9°F (1964)1.45 in6.01.7 in19.17430
December38°F20°F74°F (2021)-23°F (1989)1.22 in6.85.8 in29.01,1240
Year63°F42°F31.86 in10327.1 in1355,8331,294

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.

31.9 in in a normal year, most in May.

Chance of a wet day

The chance of at least 0.01 inch of precipitation on each date at Underwood, 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 Omaha Eppley Airfield.

27.1 in of snow in a normal year.

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Omaha Eppley Airfield. 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 18 and the first fall freeze around October 21, a growing season of about 185 days.

Median at 36°F
last April 28, first October 10
Median at 32°F
last April 18, first October 21
Median at 28°F
last April 8, first October 30

Frost dates, growing season and degree days

Humidity and comfort

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

The muggiest month is July, when 50 percent of days are muggy or worse, with a mean dew point of 65°F or more.

MonthDew pointHumidityDryComfortableHumidMuggyOppressiveMiserable
January17°F83%100%0%0%0%0%0%
February20°F79%100%0%0%0%0%0%
March29°F74%98%1%0%0%0%0%
April39°F70%95%4%1%0%0%0%
May51°F71%63%18%12%6%0%0%
June61°F73%21%22%20%26%11%1%
July64°F70%9%18%24%27%21%2%
August62°F68%19%22%25%22%11%1%
September53°F67%58%17%13%8%3%0%
October41°F70%90%6%3%1%0%0%
November29°F76%99%1%0%0%0%0%
December21°F83%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 46 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 13.0 mph at 10 meters (33 feet) above the ground.

Daylight and sunshine

The longest day is Jun 20, with 15 h 11 min of daylight; the shortest is Dec 18, with 9 h 11 min.

Hours of daylight at Underwood 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 Pottawattamie 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 Pottawattamie County: 73.4°F (+0.7 °F against 1991-2020), the 52nd warmest in 132 years on record.

August 2026 in Pottawattamie County: 5.75 in (+1.39 in against 1991-2020), the 26th wettest in 132 years on record.

January to August 2026 in Pottawattamie County: 55.1°F (+2.7 °F against 1991-2020), the 6th warmest in 132 years on record.

January to August 2026 in Pottawattamie County: 21.75 in (-3.97 in against 1991-2020), the 54th driest in 132 years on record.

Warmest August
81.0°F in 1936
Coolest August
66.3°F in 1915
Wettest August
11.26 in in 1903
Driest August
0.49 in in 2003

Every year since 1895

Each year's average temperature in Pottawattamie 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 Underwood 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 1948. 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 USW00014942 (Omaha Eppley Airfield), public domain. Records: NOAA GHCN-Daily, station USW00014942, 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.