Photo: Jared Winkler · CC BY-SA 4.0Midwinter lows in Underwood sink below those of 89% of U.S. towns
Midsummer highs settle at about 85°. Precipitation peaks in June and eases off in January. Its yearly precipitation falls short of 79% of U.S. towns. Homes need heating from November to March, the months averaging under 50°.
A year in Underwood at a glance
Each month’s typical high and low, and what it brings.
What stands out about Underwood’s climate
Compared with towns across the U.S., with Underwood’s place in Iowa beside it.
What a year in Underwood feels like
Typical highs and lows by season and by month, from NOAA’s 30-year normals.
About 185 frost-free days a year
In half of years the last 32° night comes by April 18 and the first by October 21. Frost and day counts come from NOAA’s station at Omaha Eppley Airfield, NE, 12 miles from the town’s center, at about the same height.
The 2023 USDA map puts Underwood’s center in zone 5b: the coldest night of a typical winter, averaged over 1991–2020, reaches about −11°. Plant labels use the zone; frost dates tell you when to plant.
Freezing nights by month
Average nights at or below 32°
90° days by month
Average days at 90° or more
About 27 inches of snow a winter
Snow, measured at Underwood, IA, falls mostly in February. Precipitation (rain plus melted snow) adds up to 34 inches a year; June is the wettest month and January the driest. Rain or snow falls on about 71 days a year.
Rain + melted snow by month
Inches of water
Snowfall by month
Inches of snow
Heating and cooling a home in Underwood
82% of the work is heating. Months averaging under 55° run from October through April.
Degree days add up how far each day’s average falls below (heating) or rises above (cooling) 65° over a year. NOAA normals at Omaha Eppley Airfield, NE.
Living with Underwood’s climate
What the numbers mean for a garden, a free afternoon and a bad-weather day.
185 frost-free days in zone 5b. The last frost comes by Apr 18 in half of years, so many gardeners wait a week or two past that to set out tomatoes. The first fall frost comes by Oct 21.
Months with highs of 62–84° and lows of 40° or more: May, June, August, September and October. 0.1 miles of trails are waiting.
Parks & trails →Of the yearly building losses FEMA expects in Underwood from natural hazards, river flooding is the largest share (34%); heat waves, cold waves, winter storms and ice storms together are 11%. Normals are averages; the hazards page covers the extremes.
Natural hazards →Underwood and similar climates
TownRatings has no climate map of the towns around Underwood yet.
Climates most like Underwood’s, farther away
TownRatings’ own comparison of NOAA 1991–2020 normals, not a NOAA product: places of 5,000+ at least 150 miles away, one per state, closest on January low, July high, precipitation and snow.
| Town | Jan. low | July high | Precip. | Snow |
|---|---|---|---|---|
| Underwood, IA | 13° | 85° | 34" | 27" |
| Spring Valley, IL | 15° | 85° | 37" | 29" |
| Tecumseh, MI | 17° | 84° | 34" | 26" |
| Wauseon, OH | 18° | 84° | 35" | 27" |
| Beloit, WI | 13° | 83° | 37" | 37" |
Temperatures and precipitation come from NOAA’s 5 km grid; snow and day counts from the stations named on this page.
Warmer than it used to be
The last 30 years in Underwood averaged 0.9° warmer than the 1900s. The biggest change is in March (+2.2°).
A smaller shift than in 87% of U.S. towns.
Change by month
The two periods overlap (1991–2000 is in both), which makes the gap a little smaller than it would be between separate periods.
How Underwood compares
Against 12,954 U.S. towns of 2,500 or more (one per 5 km climate cell), with Underwood’s place among Iowa’s.
Underwood weather by month
Highs, lows and precipitation from NOAA’s grid at Underwood’s center; snow, wet days and snow on the ground from Underwood, IA. 1991–2020 normals.
| Month | High | Low | Rain + melt | Snow | Wet days | Snow on ground | 30-yr range |
|---|---|---|---|---|---|---|---|
| January | 31° | 13° | 0.8" | 5.5" | 3 | 16 | 15° – 36° |
| February | 37° | 17° | 1.0" | 9.7" | 4 | 15 | 16° – 36° |
| March | 50° | 28° | 1.9" | 3.1" | 5 | 3 | 32° – 54° |
| April | 62° | 39° | 3.4" | 0.8" | 7 | 0 | 43° – 57° |
| May | 73° | 50° | 5.0" | 0.2" | 10 | 0 | 57° – 69° |
| June | 82° | 61° | 5.2" | 0.0" | 8 | 0 | 67° – 76° |
| July | 85° | 65° | 3.8" | 0.0" | 6 | 0 | 70° – 81° |
| August | 83° | 62° | 4.3" | 0.0" | 7 | 0 | 67° – 77° |
| September | 77° | 53° | 3.4" | 0.0" | 6 | 0 | 59° – 71° |
| October | 64° | 41° | 2.6" | 0.7" | 6 | 0 | 46° – 57° |
| November | 49° | 28° | 1.4" | 0.8" | 3 | 1 | 29° – 49° |
| December | 36° | 18° | 1.2" | 6.5" | 4 | 10 | 13° – 33° |
| Year | 61° | 40° | 34.1" | 27.3" | 71 | 46 |
How much a month can swing
A normal is an average. March swings the most: from 1991 to 2020 its average ranged from 32° to 54°. June is the most reliable, staying within 9°.
Where Underwood’s numbers come from
Normals are 30-year averages, not a forecast. How TownRatings reads climate data →
- Temperatures and precipitation: NOAA’s gridded 1991–2020 normals for the 5 km cell at Underwood’s center.
- Snow: Underwood, IA (NOAA station in town).
- Frost, freezing nights, 90° and 100° days, heating and cooling: Omaha Eppley Airfield, NE, 12 miles from the town’s center, at about the same height; the nearest station that passes our checks for distance, height and agreement with the grid.
- Growing zone: USDA Plant Hardiness Zone Map, 2023. USDA Agricultural Research Service and PRISM Group, Oregon State University, prism.oregonstate.edu/phzm, accessed 8 Oct 2026.
- Then and now: NOAA’s gridded normals for 1901–2000 at the same cell.
- Storms and extremes: FEMA National Risk Index (expected annual losses to buildings).
Common questions about Underwood’s climate
What is the weather like in Underwood?
A typical July afternoon reaches 85°, a January night drops to 13°, and about 27 inches of snow falls in a normal winter. Colder January nights than 89% of U.S. towns; hotter July afternoons than 51% of U.S. towns.
How cold does it get in Underwood in winter?
January nights average 13°. About 135 nights a year reach 32° or below and 9 reach 0° or below. In the coldest January of the last 30 years the month averaged 15°.
How much snow does Underwood get?
About 27 inches in a normal winter at Underwood, IA, most of it in February, with snow on the ground about 46 days a year.
How hot does it get in Underwood?
July, with a typical high of 85° and a low of 65°. About 33 days a year reach 90° and 2 reach 100° (Omaha Eppley Airfield, NE).
When is the first and last frost in Underwood?
In half of years the last spring frost (32°) comes by April 18 and the first fall frost by October 21, about 185 frost-free days, at Omaha Eppley Airfield, NE.
What growing zone is Underwood in?
Zone 5b on the 2023 USDA Plant Hardiness Zone Map: the coldest night of a typical winter reaches about −11°.
What is the best time of year to visit Underwood?
By one simple rule (highs of 62–84° and lows of 40° or more), May, June, August, September and October. The rule is ours, not NOAA’s; the month table has the numbers to judge by.
Is Underwood getting warmer?
Yes: 1991–2020 averaged 0.9° warmer than 1901–2000 on NOAA’s grid. A smaller shift than 87% of U.S. towns.
Neighbors talk weather
Gardens, snow, and the best days of the year in Underwood.
Source: NOAA NCEI U.S. Climate Normals, 1991–2020 and 1901–2000; USDA/PRISM 2023 hardiness zones; FEMA National Risk Index. Today’s forecast: National Weather Service.