Weldon Spring, MO climate
Weldon Spring has chilly winters and warm summers. A typical July afternoon reaches 89°, 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 Weldon Spring feels like
Winter
Spring
Summer
Fall
Weldon Spring 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 | Snow on ground | 30-yr range |
|---|---|---|---|---|---|---|---|
| January | 40° | 22° | 2.5" | 4.1" | 8 | 5 | 25° – 42° |
| February | 45° | 26° | 2.3" | 3.7" | 8 | 4 | 26° – 46° |
| March | 56° | 35° | 3.6" | 1.7" | 10 | 1 | 38° – 59° |
| April | 68° | 44° | 4.7" | 0.2" | 10 | 0 | 49° – 62° |
| May | 77° | 55° | 5.0" | 0 | 13 | 0 | 61° – 73° |
| June | 85° | 64° | 4.5" | 0 | 10 | 0 | 69° – 79° |
| July | 89° | 68° | 3.7" | 0 | 8 | 0 | 73° – 85° |
| August | 87° | 66° | 3.7" | 0 | 8 | 0 | 71° – 82° |
| September | 80° | 58° | 3.3" | 0 | 7 | 0 | 64° – 76° |
| October | 69° | 46° | 3.2" | 0 | 9 | 0 | 52° – 63° |
| November | 55° | 36° | 3.4" | 0.8" | 8 | 1 | 38° – 52° |
| December | 44° | 27° | 2.6" | 3.0" | 8 | 4 | 22° – 44° |
| Year | 66° | 45° | 42.5" | 13.5" | 107 | 15 |
“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 Weldon Spring
Weldon Spring gets 42 inches of rain and melted snow a year. May is the wettest month and February the driest. Rain or snow falls on about 107 days a year. Snow covers the ground about 15 days of the year.
About 199 frost-free days a year
In half of years the last 32° night comes by April 10 and the first one by October 26. That leaves about 199 frost-free days for gardens, longer than 72% of U.S. towns.
Heating and cooling a home in Weldon Spring
Engineers use “degree days” to estimate how hard a furnace or air conditioner works. In Weldon Spring, 79% of that work is heating and 21% is cooling.
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.
Weldon Spring and its neighbors
Weldon Spring borders 3 towns with climate data. January nights across them vary by 0.7°. O'Fallon has the coldest January nights (22°) and St. Peters the hottest July afternoons (89°). Weldon Spring’s January low is 22° and its July high 89°.
Temperatures and rain come from NOAA’s 5 km grid, so each town gets its own value.
How Weldon Spring 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 Weldon Spring averaged 1.0° warmer than the 1900s. The biggest change is in December (+2.2°). The shift is smaller than in 74% of U.S. towns.
Change by month1991–2020 average minus 1901–2000 average, at Weldon Spring’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 22° to 44°. June is the most reliable, staying within 9°.
Common questions about Weldon Spring’s climate
What is the coldest month in Weldon Spring?
January, with a typical high of 40° and a low of 22°.
What is the hottest month in Weldon Spring?
July, with a typical high of 89° and a low of 68°. About 36 days a year reach 90°.
How much snow does Weldon Spring get?
About 14 inches in a normal winter, most of it in January.
When is the first frost in Weldon Spring?
In half of years the first 32° night comes by October 26, and the last spring frost by April 10.
What is the rainiest month in Weldon Spring?
May, with 5.0 inches of rain and melted snow. The year totals 42 inches.
Temperatures and rainfall come from NOAA’s gridded climate normals for Weldon Spring itself (about a 3-mile square). Snow, frost dates and day counts come from NOAA’s weather station at Weldon Spring Nws, MO (2 mi) away. Normals are 30-year averages, not a forecast. Source: NOAA NCEI U.S. Climate Normals, 1991–2020 and 1901–2000.