Photo: Jared Winkler · CC BY-SA 4.0Randolph has colder winter nights than 86% of U.S. towns
On a normal July day the thermometer tops out near 86°. Only 72° separates winter nights from summer afternoons. Its yearly precipitation falls short of 79% of U.S. towns. If you like long walks, May, June, September and October offer highs of 66–83°.
A year in Randolph at a glance
Each month’s typical high and low, and what it brings.
What stands out about Randolph’s climate
Compared with towns across the U.S., with Randolph’s place in Iowa beside it.
What a year in Randolph feels like
Typical highs and lows by season and by month, from NOAA’s 30-year normals.
About 182 frost-free days a year
In half of years the last 32° night comes by April 19 and the first by October 19. Frost and day counts come from NOAA’s station at Sidney 1sse, IA, 10 miles from the town’s center, 170 ft higher.
The 2023 USDA map puts Randolph’s center in zone 5b: the coldest night of a typical winter, averaged over 1991–2020, reaches about −12°. 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 24 inches of snow a winter
Snow, measured at Randolph, IA, is heaviest from January through February, about 7 inches a month. Precipitation (rain plus melted snow) adds up to 34 inches a year; May is the wettest month and January the driest. Rain or snow falls on about 99 days a year.
Rain + melted snow by month
Inches of water
Snowfall by month
Inches of snow
Heating and cooling a home in Randolph
86% of the work is heating, so the furnace matters far more than the air conditioner. 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 Sidney 1sse, IA.
Living with Randolph’s climate
What the numbers mean for a garden, a free afternoon and a bad-weather day.
182 frost-free days in zone 5b. The last frost comes by Apr 19 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 19.
Months with highs of 62–84° and lows of 40° or more: May, June, September and October.
Parks & trails →Of the yearly building losses FEMA expects in Randolph from natural hazards, river flooding is the largest share (38%); heat waves, cold waves, winter storms and ice storms together are 12%. Normals are averages; the hazards page covers the extremes.
Natural hazards →Randolph and similar climates
TownRatings has no climate map of the towns around Randolph yet.
Climates most like Randolph’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 |
|---|---|---|---|---|
| Randolph, IA | 14° | 86° | 34" | 24" |
| Chillicothe, IL | 16° | 86° | 37" | 20" |
| Napoleon, OH | 19° | 85° | 36" | 25" |
| Tecumseh, MI | 17° | 84° | 34" | 26" |
| Kirksville, MO | 17° | 86° | 41" | 19" |
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 Randolph averaged 0.8° warmer than the 1900s. The biggest change is in March (+2.3°).
A smaller shift than in 91% 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 Randolph compares
Against 12,954 U.S. towns of 2,500 or more (one per 5 km climate cell), with Randolph’s place among Iowa’s.
Randolph weather by month
Highs, lows and precipitation from NOAA’s grid at Randolph’s center; snow, wet days and snow on the ground from Randolph, IA. 1991–2020 normals.
| Month | High | Low | Rain + melt | Snow | Wet days | Snow on ground | 30-yr range |
|---|---|---|---|---|---|---|---|
| January | 33° | 14° | 0.8" | 7.4" | 6 | 18 | 16° – 37° |
| February | 39° | 19° | 1.1" | 6.8" | 6 | 14 | 18° – 38° |
| March | 52° | 30° | 1.9" | 2.1" | 7 | 4 | 33° – 56° |
| April | 64° | 40° | 3.3" | 1.1" | 10 | 0 | 43° – 58° |
| May | 74° | 51° | 5.4" | 0.0" | 13 | 0 | 57° – 70° |
| June | 83° | 62° | 5.1" | 0.0" | 11 | 0 | 68° – 77° |
| July | 86° | 66° | 4.1" | 0.0" | 10 | 0 | 71° – 82° |
| August | 85° | 63° | 3.6" | 0.0" | 9 | 0 | 68° – 78° |
| September | 78° | 54° | 3.2" | 0.0" | 8 | 0 | 59° – 72° |
| October | 66° | 42° | 2.7" | 0.6" | 8 | 0 | 47° – 58° |
| November | 50° | 30° | 1.6" | 1.4" | 6 | 1 | 30° – 50° |
| December | 38° | 19° | 1.3" | 4.6" | 6 | 10 | 15° – 34° |
| Year | 62° | 41° | 34.1" | 24.0" | 99 | 47 |
How much a month can swing
A normal is an average. March swings the most: from 1991 to 2020 its average ranged from 33° to 56°. June is the most reliable, staying within 8°.
Where Randolph’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 Randolph’s center.
- Snow: Randolph, IA (NOAA station in town).
- Frost, freezing nights, 90° and 100° days, heating and cooling: Sidney 1sse, IA, 10 miles from the town’s center, 170 ft higher; 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 Randolph’s climate
What is the weather like in Randolph?
A typical July afternoon reaches 86°, a January night drops to 14°, and about 24 inches of snow falls in a normal winter. Colder January nights than 86% of U.S. towns; hotter July afternoons than 58% of U.S. towns.
How cold does it get in Randolph in winter?
January nights average 14°. About 134 nights a year reach 32° or below and 11 reach 0° or below. In the coldest January of the last 30 years the month averaged 16°.
How much snow does Randolph get?
About 24 inches in a normal winter at Randolph, IA, heaviest from January through February, about 7 inches a month, with snow on the ground about 47 days a year.
How hot does it get in Randolph?
July, with a typical high of 86° and a low of 66°. About 24 days a year reach 90° (Sidney 1sse, IA).
When is the first and last frost in Randolph?
In half of years the last spring frost (32°) comes by April 19 and the first fall frost by October 19, about 182 frost-free days, at Sidney 1sse, IA.
What growing zone is Randolph in?
Zone 5b on the 2023 USDA Plant Hardiness Zone Map: the coldest night of a typical winter reaches about −12°.
What is the best time of year to visit Randolph?
By one simple rule (highs of 62–84° and lows of 40° or more), May, June, September and October. The rule is ours, not NOAA’s; the month table has the numbers to judge by.
Is Randolph getting warmer?
Yes: 1991–2020 averaged 0.8° warmer than 1901–2000 on NOAA’s grid. A smaller shift than 91% of U.S. towns.
Neighbors talk weather
Gardens, snow, and the best days of the year in Randolph.
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.