Photo: Brian M. Powell (user Bitmapped on en.wikipedia) · CC BY-SA 3.0Few U.S. towns have colder winter nights than Sibley
July afternoons average 83°. Temperatures cover 77° across the year, low to high. Precipitation is light here, less than falls on 85% of U.S. towns. Long walks are most pleasant from May to September, when afternoons reach 69–83°.
A year in Sibley at a glance
Each month’s typical high and low, and what it brings.
What stands out about Sibley’s climate
Compared with towns across the U.S., with Sibley’s place in Iowa beside it.
What a year in Sibley 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 5 and the first by October 3. Frost and day counts come from NOAA’s station at Sibley, IA, 0.4 miles from the town’s center, at about the same height.
The 2023 USDA map puts Sibley’s center in zone 5a: 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 42 inches of snow a winter
Snow, measured at Sibley, IA, falls mostly in December. Precipitation (rain plus melted snow) adds up to 30 inches a year; June is the wettest month and January the driest. Rain or snow falls on about 97 days a year.
Rain + melted snow by month
Inches of water
Snowfall by month
Inches of snow
Heating and cooling a home in Sibley
93% 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 Sibley, IA.
Living with Sibley’s climate
What the numbers mean for a garden, a free afternoon and a bad-weather day.
152 frost-free days in zone 5a. The last frost comes by May 5 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 3.
Months with highs of 62–84° and lows of 40° or more: May, June, July, August and September. 2.8 miles of trails are waiting.
Parks & trails →Of the yearly building losses FEMA expects in Sibley from natural hazards, river flooding is the largest share (35%); heat waves, cold waves, winter storms and ice storms together are 23%. Normals are averages; the hazards page covers the extremes.
Natural hazards →Sibley and similar climates
TownRatings has no climate map of the towns around Sibley yet.
Climates most like Sibley’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 |
|---|---|---|---|---|
| Sibley, IA | 6° | 83° | 30" | 42" |
| St. Paul, MN | 7° | 83° | 33" | 40" |
| Hudson, WI | 6° | 82° | 33" | 50" |
| Plattsburgh, NY | 9° | 81° | 35" | 50" |
| Wahpeton, ND | 1° | 82° | 25" | 50" |
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 Sibley averaged 0.7° warmer than the 1900s. The biggest change is in January (+1.9°).
A smaller shift than in 94% 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 Sibley compares
Against 12,954 U.S. towns of 2,500 or more (one per 5 km climate cell), with Sibley’s place among Iowa’s.
Sibley weather by month
Highs, lows and precipitation from NOAA’s grid at Sibley’s center; snow, wet days and snow on the ground from Sibley, IA. 1991–2020 normals.
| Month | High | Low | Rain + melt | Snow | Wet days | Snow on ground | 30-yr range |
|---|---|---|---|---|---|---|---|
| January | 24° | 6° | 0.7" | 8.1" | 6 | 28 | 5° – 29° |
| February | 29° | 11° | 0.8" | 7.4" | 5 | 22 | 9° – 32° |
| March | 42° | 23° | 1.6" | 7.0" | 6 | 13 | 24° – 48° |
| April | 57° | 34° | 3.1" | 3.7" | 10 | 2 | 35° – 53° |
| May | 69° | 46° | 4.1" | 0.0" | 13 | 0 | 52° – 64° |
| June | 80° | 57° | 4.9" | 0.0" | 12 | 0 | 63° – 73° |
| July | 83° | 61° | 3.6" | 0.0" | 9 | 0 | 64° – 79° |
| August | 80° | 58° | 3.5" | 0.0" | 9 | 0 | 64° – 73° |
| September | 74° | 49° | 3.2" | 0.0" | 8 | 0 | 55° – 67° |
| October | 60° | 37° | 2.4" | 1.1" | 8 | 0 | 41° – 53° |
| November | 43° | 23° | 1.4" | 5.1" | 5 | 7 | 23° – 45° |
| December | 29° | 12° | 1.0" | 9.1" | 6 | 20 | 6° – 27° |
| Year | 56° | 35° | 30.3" | 41.5" | 97 | 91 |
How much a month can swing
A normal is an average. January swings the most: from 1991 to 2020 its average ranged from 5° to 29°. August is the most reliable, staying within 9°.
Where Sibley’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 Sibley’s center.
- Snow: Sibley, IA (NOAA station in town).
- Frost, freezing nights, 90° and 100° days, heating and cooling: Sibley, IA, 0.4 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 Sibley’s climate
What is the weather like in Sibley?
A typical July afternoon reaches 83°, a January night drops to 6°, and about 42 inches of snow falls in a normal winter. Colder January nights than 97% of U.S. towns; cooler July afternoons than 69% of U.S. towns.
How cold does it get in Sibley in winter?
January nights average 6°. About 173 nights a year reach 32° or below and 33 reach 0° or below. In the coldest January of the last 30 years the month averaged 5°.
How much snow does Sibley get?
About 42 inches in a normal winter at Sibley, IA, most of it in December, with snow on the ground about 91 days a year.
How hot does it get in Sibley?
July, with a typical high of 83° and a low of 61°. About 10 days a year reach 90° (Sibley, IA).
When is the first and last frost in Sibley?
In half of years the last spring frost (32°) comes by May 5 and the first fall frost by October 3, about 152 frost-free days, at Sibley, IA.
What growing zone is Sibley in?
Zone 5a 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 Sibley?
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 Sibley getting warmer?
Yes: 1991–2020 averaged 0.7° warmer than 1901–2000 on NOAA’s grid. A smaller shift than 94% of U.S. towns.
Neighbors talk weather
Gardens, snow, and the best days of the year in Sibley.
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.