Lewisville, WA climate
Lewisville has mild winters and pleasant summers, with plenty of rain. A typical July afternoon reaches 80°, a January night drops to 35°, and about 3 inches of snow falls in a normal winter.
NOAA 1991-2020 climate normals Updated once a decadeWhat a year in Lewisville feels like
Winter
Spring
Summer
Fall
Lewisville 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 | 46° | 35° | 8.4" | 1.6" | 21 | 1 | 33° – 45° |
| February | 50° | 35° | 6.3" | 0.9" | 18 | 1 | 36° – 48° |
| March | 55° | 37° | 6.5" | 0.2" | 20 | 0 | 43° – 51° |
| April | 60° | 40° | 5.3" | 0 | 19 | 0 | 46° – 55° |
| May | 68° | 46° | 3.7" | 0 | 14 | 0 | 52° – 60° |
| June | 72° | 50° | 2.7" | 0 | 11 | 0 | 57° – 67° |
| July | 80° | 54° | 0.7" | 0 | 4 | 0 | 62° – 70° |
| August | 80° | 54° | 1.0" | 0 | 4 | 0 | 63° – 70° |
| September | 75° | 50° | 2.5" | 0 | 9 | 0 | 59° – 64° |
| October | 62° | 43° | 5.6" | 0 | 15 | 0 | 49° – 57° |
| November | 52° | 38° | 8.9" | 0 | 20 | 0 | 39° – 50° |
| December | 45° | 34° | 9.2" | 0.3" | 21 | 0 | 35° – 43° |
| Year | 62° | 43° | 60.8" | 3.0" | 176 | 2 |
“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 Lewisville
Lewisville gets 61 inches of rain and melted snow a year. December is the wettest month and July the driest. Rain or snow falls on about 176 days a year.
About 174 frost-free days a year
In half of years the last 32° night comes by April 26 and the first one by October 16. That leaves about 174 frost-free days for gardens, shorter than 56% of U.S. towns.
Heating and cooling a home in Lewisville
Engineers use “degree days” to estimate how hard a furnace or air conditioner works. In Lewisville, 97% of that work is heating and 3% 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.
Lewisville and its neighbors
Lewisville borders 3 towns with climate data. January nights across them vary by 0.2°. Battle Ground has both the coldest January nights (35°) and the hottest July afternoons (80°). Lewisville’s January low is 35° and its July high 80°.
Temperatures and rain come from NOAA’s 5 km grid, so each town gets its own value.
How Lewisville 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 Lewisville averaged 1.3° warmer than the 1900s. The biggest change is in January (+3.2°). The shift is larger than in 53% of U.S. towns.
Change by month1991–2020 average minus 1901–2000 average, at Lewisville’s spot on NOAA’s grid
How much a month can swing
A normal is an average, and real years wander around it. January swings the most: between 1991 and 2020 its average temperature ranged from 33° to 45°. September is the most reliable, staying within 6°.
Common questions about Lewisville’s climate
What is the coldest month in Lewisville?
December, with a typical high of 45° and a low of 34°.
What is the hottest month in Lewisville?
August, with a typical high of 80° and a low of 54°. About 11 days a year reach 90°.
How much snow does Lewisville get?
About 3 inches in a normal winter, most of it in January.
When is the first frost in Lewisville?
In half of years the first 32° night comes by October 16, and the last spring frost by April 26.
What is the rainiest month in Lewisville?
December, with 9.2 inches of rain and melted snow. The year totals 61 inches.
Temperatures and rainfall come from NOAA’s gridded climate normals for Lewisville itself (about a 3-mile square). Snow, frost dates and day counts come from NOAA’s weather station at Merwin Dam, WA (10 mi, snow) and Battle Ground, WA (3 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.