Photo: KRS9400 · CC BY-SA 4.0Few U.S. towns have colder winter nights than Northwood
July afternoons average 81°. Expect the heaviest rain or snow in June and the lightest in January. Summers stay cool: July afternoons here are cooler than in 86% of U.S. towns. The heating season runs October to April: each of those months averages under 50°.
A year in Northwood at a glance
Each month’s typical high and low, and what it brings.
What stands out about Northwood’s climate
Compared with towns across the U.S., with Northwood’s place in Iowa beside it.
What a year in Northwood feels like
Typical highs and lows by season and by month, from NOAA’s 30-year normals.
About 152 frost-free days a year
In half of years the last 32° night comes by May 4 and the first by October 4. Frost and day counts come from NOAA’s station at Northwood, IA, 0.6 miles from the town’s center, at about the same height.
The 2023 USDA map puts Northwood’s center in zone 4b: the coldest night of a typical winter, averaged over 1991–2020, reaches about −20°. 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 40 inches of snow a winter
Snow, measured at Northwood, IA, falls mostly in January. Precipitation (rain plus melted snow) adds up to 36 inches a year; June is the wettest month and January the driest. Rain or snow falls on about 101 days a year.
Rain + melted snow by month
Inches of water
Snowfall by month
Inches of snow
Heating and cooling a home in Northwood
96% 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 Northwood, IA.
Living with Northwood’s climate
What the numbers mean for a garden, a free afternoon and a bad-weather day.
152 frost-free days in zone 4b. The last frost comes by May 4 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 4.
Months with highs of 62–84° and lows of 40° or more: May, June, July, August and September. 0.3 miles of trails are waiting.
Parks & trails →Of the yearly building losses FEMA expects in Northwood from natural hazards, river flooding is the largest share (36%); heat waves, cold waves, winter storms and ice storms together are 13%. Normals are averages; the hazards page covers the extremes.
Natural hazards →Northwood and similar climates
TownRatings has no climate map of the towns around Northwood yet.
Climates most like Northwood’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 |
|---|---|---|---|---|
| Northwood, IA | 7° | 81° | 36" | 40" |
| Grand Rapids, WI | 7° | 81° | 34" | 48" |
| Plattsburgh, NY | 9° | 81° | 35" | 50" |
| Colchester, VT | 10° | 81° | 38" | 50" |
| Hanover, NH | 9° | 82° | 39" | 61" |
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 Northwood averaged 0.8° warmer than the 1900s. The biggest change is in December (+2.8°).
A smaller shift than in 89% 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 Northwood compares
Against 12,954 U.S. towns of 2,500 or more (one per 5 km climate cell), with Northwood’s place among Iowa’s.
Northwood weather by month
Highs, lows and precipitation from NOAA’s grid at Northwood’s center; snow, wet days and snow on the ground from Northwood, IA. 1991–2020 normals.
| Month | High | Low | Rain + melt | Snow | Wet days | 30-yr range |
|---|---|---|---|---|---|---|
| January | 23° | 7° | 0.9" | 10.9" | 8 | 4° – 28° |
| February | 28° | 11° | 1.0" | 9.3" | 6 | 9° – 31° |
| March | 41° | 23° | 2.0" | 6.2" | 8 | 24° – 48° |
| April | 56° | 35° | 3.8" | 3.3" | 10 | 34° – 53° |
| May | 69° | 47° | 4.9" | 0.0" | 12 | 52° – 64° |
| June | 79° | 57° | 5.6" | 0.0" | 11 | 65° – 73° |
| July | 81° | 61° | 4.7" | 0.0" | 9 | 65° – 77° |
| August | 79° | 58° | 4.0" | 0.0" | 8 | 63° – 74° |
| September | 73° | 50° | 3.5" | 0.0" | 8 | 55° – 67° |
| October | 59° | 37° | 2.6" | 0.3" | 8 | 42° – 54° |
| November | 43° | 25° | 1.7" | 2.6" | 7 | 25° – 46° |
| December | 29° | 14° | 1.3" | 7.6" | 7 | 6° – 30° |
| Year | 55° | 35° | 35.9" | 40.2" | 101 |
How much a month can swing
A normal is an average. March swings the most: from 1991 to 2020 its average ranged from 24° to 48°. June is the most reliable, staying within 8°.
Where Northwood’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 Northwood’s center.
- Snow: Northwood, IA (NOAA station in town).
- Frost, freezing nights, 90° and 100° days, heating and cooling: Northwood, IA, 0.6 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 Northwood’s climate
What is the weather like in Northwood?
A typical July afternoon reaches 81°, a January night drops to 7°, and about 40 inches of snow falls in a normal winter. Colder January nights than 97% of U.S. towns; cooler July afternoons than 86% of U.S. towns.
How cold does it get in Northwood in winter?
January nights average 7°. About 165 nights a year reach 32° or below and 30 reach 0° or below. In the coldest January of the last 30 years the month averaged 4°.
How much snow does Northwood get?
About 40 inches in a normal winter at Northwood, IA, most of it in January.
How hot does it get in Northwood?
July, with a typical high of 81° and a low of 61°. About 4 days a year reach 90° (Northwood, IA).
When is the first and last frost in Northwood?
In half of years the last spring frost (32°) comes by May 4 and the first fall frost by October 4, about 152 frost-free days, at Northwood, IA.
What growing zone is Northwood in?
Zone 4b on the 2023 USDA Plant Hardiness Zone Map: the coldest night of a typical winter reaches about −20°.
What is the best time of year to visit Northwood?
By one simple rule (highs of 62–84° and lows of 40° or more), May, June, July, August and September. The rule is ours, not NOAA’s; the month table has the numbers to judge by.
Is Northwood getting warmer?
Yes: 1991–2020 averaged 0.8° warmer than 1901–2000 on NOAA’s grid. A smaller shift than 89% of U.S. towns.
Neighbors talk weather
Gardens, snow, and the best days of the year in Northwood.
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.