Ste. Marie, IL climate
Ste. Marie has chilly winters and warm summers. A typical July afternoon reaches 87°, a January night drops to 22°, and about 14 inches of snow falls in a normal winter.
NOAA 1991-2020 climate normals Updated once a decadeWhat a year in Ste. Marie feels like
Winter
Spring
Summer
Fall
Ste. Marie weather by month
Average highs, lows, rain and snow for every month, from NOAA’s 1991–2020 normals.
| Month | High | Low | Rain + melt | Snow | Wet days | 30-yr range |
|---|---|---|---|---|---|---|
| January | 38° | 22° | 3.1" | 5.4" | 9 | 23° – 41° |
| February | 43° | 25° | 2.4" | 2.7" | 8 | 21° – 43° |
| March | 54° | 34° | 3.5" | 1.1" | 9 | 36° – 58° |
| April | 66° | 44° | 4.8" | 0 | 10 | 48° – 61° |
| May | 75° | 55° | 4.8" | 0 | 11 | 59° – 73° |
| June | 84° | 63° | 4.9" | 0 | 9 | 69° – 77° |
| July | 87° | 66° | 4.4" | 0 | 8 | 71° – 84° |
| August | 86° | 64° | 3.3" | 0 | 7 | 70° – 81° |
| September | 80° | 57° | 3.2" | 0 | 7 | 64° – 74° |
| October | 68° | 45° | 3.7" | 0.2" | 7 | 52° – 62° |
| November | 53° | 35° | 3.8" | 0.6" | 9 | 37° – 51° |
| December | 42° | 27° | 3.0" | 4.2" | 9 | 21° – 44° |
| Year | 65° | 45° | 45.0" | 14.2" | 101 |
“Wet days” have at least 0.01" of rain or melted snow. “Snow on ground” counts days with 1" or more. The 30-year range is the coldest and warmest that month’s average temperature got between 1991 and 2020.
Rain and snow in Ste. Marie
Ste. Marie gets 45 inches of rain and melted snow a year. June is the wettest month and February the driest. Rain or snow falls on about 101 days a year.
About 190 frost-free days a year
In half of years the last 32° night comes by April 13 and the first one by October 22. That leaves about 190 frost-free days for gardens, longer than 64% of U.S. towns.
Heating and cooling a home in Ste. Marie
Engineers use “degree days” to estimate how hard a furnace or air conditioner works. In Ste. Marie, 80% of that work is heating and 20% is cooling, so the furnace matters far more than the air conditioner.
Degree days measure how far each day’s average temperature falls below or rises above 65°, added up over a year. Source: NOAA station normals.
How Ste. Marie compares
Compared with every U.S. town and city on TownTapestry, each counted once.
Warmer than it used to be
The last 30 years in Ste. Marie averaged 0.9° warmer than the 1900s. The biggest change is in December (+1.9°). The shift is smaller than in 78% of U.S. towns.
Change by month1991–2020 average minus 1901–2000 average, at Ste. Marie’s spot on NOAA’s grid
How much a month can swing
A normal is an average, and real years wander around it. December swings the most: between 1991 and 2020 its average temperature ranged from 21° to 44°. June is the most reliable, staying within 8°.
Common questions about Ste. Marie’s climate
What is the coldest month in Ste. Marie?
January, with a typical high of 38° and a low of 22°.
What is the hottest month in Ste. Marie?
July, with a typical high of 87° and a low of 66°. About 30 days a year reach 90°.
How much snow does Ste. Marie get?
About 14 inches in a normal winter, most of it in January.
When is the first frost in Ste. Marie?
In half of years the first 32° night comes by October 22, and the last spring frost by April 13.
What is the rainiest month in Ste. Marie?
June, with 4.9 inches of rain and melted snow. The year totals 45 inches.
Temperatures and rainfall come from NOAA’s gridded climate normals for Ste. Marie itself (about a 3-mile square). Snow, frost dates and day counts come from NOAA’s weather station at Ste Marie (river), IL (1 mi, snow) and Newton, IL (9 mi, frost, heat and degree days). Normals are 30-year averages, not a forecast. Source: NOAA NCEI U.S. Climate Normals, 1991–2020 and 1901–2000.