Photo: Boscophotos · CC BY-SA 3.0Winter nights in Montezuma are colder than in 91% of U.S. towns
Midsummer highs settle at about 84°. It is a dry place: less rain and snow fall here than on 69% of U.S. towns. The latest 30-year average runs 0.8° warmer than 1901–2000’s, with December up the most. The frost-free window for a garden runs roughly May 3 to October 6.
A year in Montezuma at a glance
Each month’s typical high and low, and what it brings.
What stands out about Montezuma’s climate
Compared with towns across the U.S., with Montezuma’s place in Iowa beside it.
What a year in Montezuma feels like
Typical highs and lows by season and by month, from NOAA’s 30-year normals.
About 155 frost-free days a year
In half of years the last 32° night comes by May 3 and the first by October 6. Frost and day counts come from NOAA’s station at Grinnell 3 Sw, IA, 15 miles from the town’s center, at about the same height.
The 2023 USDA map puts Montezuma’s center in zone 5b: the coldest night of a typical winter, averaged over 1991–2020, reaches about −15°. 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 30 inches of snow a winter
Snow, measured at Montezuma 1 W, IA, falls mostly in January and December. Precipitation (rain plus melted snow) adds up to 38 inches a year; June is the wettest month and January the driest. Rain or snow falls on about 103 days a year.
Rain + melted snow by month
Inches of water
Snowfall by month
Inches of snow
Heating and cooling a home in Montezuma
91% 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 Grinnell 3 Sw, IA.
Living with Montezuma’s climate
What the numbers mean for a garden, a free afternoon and a bad-weather day.
155 frost-free days in zone 5b. The last frost comes by May 3 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 6.
Months with highs of 62–84° and lows of 40° or more: May, June, August, September and October. 0.0 miles of trails are waiting.
Parks & trails →Of the yearly building losses FEMA expects in Montezuma from natural hazards, drought is the largest share (28%); heat waves, cold waves, winter storms and ice storms together are 12%. Normals are averages; the hazards page covers the extremes.
Natural hazards →Montezuma and similar climates
TownRatings has no climate map of the towns around Montezuma yet.
Climates most like Montezuma’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 |
|---|---|---|---|---|
| Montezuma, IA | 12° | 84° | 38" | 30" |
| Rochelle, IL | 13° | 83° | 38" | 28" |
| Beloit, WI | 13° | 83° | 37" | 37" |
| Lowell, IN | 17° | 84° | 40" | 30" |
| Sayre, PA | 17° | 84° | 37" | 35" |
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 Montezuma averaged 0.8° warmer than the 1900s. The biggest change is in December (+2.4°).
A smaller shift than in 90% 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 Montezuma compares
Against 12,954 U.S. towns of 2,500 or more (one per 5 km climate cell), with Montezuma’s place among Iowa’s.
Montezuma weather by month
Highs, lows and precipitation from NOAA’s grid at Montezuma’s center; snow, wet days and snow on the ground from Montezuma 1 W, IA. 1991–2020 normals.
| Month | High | Low | Rain + melt | Snow | Wet days | Snow on ground | 30-yr range |
|---|---|---|---|---|---|---|---|
| January | 29° | 12° | 1.1" | 8.7" | 6 | 20 | 12° – 33° |
| February | 34° | 17° | 1.3" | 6.9" | 6 | 15 | 14° – 37° |
| March | 48° | 27° | 2.2" | 3.9" | 8 | 7 | 30° – 52° |
| April | 61° | 38° | 3.8" | 1.0" | 11 | 1 | 41° – 56° |
| May | 71° | 49° | 5.0" | 0.0" | 12 | 0 | 54° – 68° |
| June | 80° | 60° | 5.5" | 0.0" | 12 | 0 | 67° – 74° |
| July | 84° | 63° | 4.2" | 0.0" | 10 | 0 | 68° – 80° |
| August | 82° | 61° | 4.3" | 0.0" | 9 | 0 | 66° – 77° |
| September | 76° | 53° | 3.6" | 0.0" | 8 | 0 | 58° – 69° |
| October | 63° | 40° | 3.0" | 0.5" | 8 | 0 | 46° – 57° |
| November | 47° | 29° | 2.1" | 1.1" | 7 | 1 | 30° – 49° |
| December | 35° | 18° | 1.5" | 7.9" | 7 | 12 | 11° – 36° |
| Year | 59° | 39° | 37.6" | 30.0" | 103 | 56 |
How much a month can swing
A normal is an average. December swings the most: from 1991 to 2020 its average ranged from 11° to 36°. June is the most reliable, staying within 7°.
Where Montezuma’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 Montezuma’s center.
- Snow: Montezuma 1 W, IA (NOAA station in town).
- Frost, freezing nights, 90° and 100° days, heating and cooling: Grinnell 3 Sw, IA, 15 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 Montezuma’s climate
What is the weather like in Montezuma?
A typical July afternoon reaches 84°, a January night drops to 12°, and about 30 inches of snow falls in a normal winter. Colder January nights than 91% of U.S. towns; cooler July afternoons than 59% of U.S. towns.
How cold does it get in Montezuma in winter?
January nights average 12°. About 157 nights a year reach 32° or below and 19 reach 0° or below. In the coldest January of the last 30 years the month averaged 12°.
How much snow does Montezuma get?
About 30 inches in a normal winter at Montezuma 1 W, IA, most of it in January and December, with snow on the ground about 56 days a year.
How hot does it get in Montezuma?
July, with a typical high of 84° and a low of 63°. About 11 days a year reach 90° (Grinnell 3 Sw, IA).
When is the first and last frost in Montezuma?
In half of years the last spring frost (32°) comes by May 3 and the first fall frost by October 6, about 155 frost-free days, at Grinnell 3 Sw, IA.
What growing zone is Montezuma in?
Zone 5b on the 2023 USDA Plant Hardiness Zone Map: the coldest night of a typical winter reaches about −15°.
What is the best time of year to visit Montezuma?
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 Montezuma getting warmer?
Yes: 1991–2020 averaged 0.8° warmer than 1901–2000 on NOAA’s grid. A smaller shift than 90% of U.S. towns.
Neighbors talk weather
Gardens, snow, and the best days of the year in Montezuma.
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.