Photo: Steven Pavlov · CC BY-SA 3.0Hardly any U.S. towns collect less precipitation than Soap Lake: 7 inches a year
In July the day’s top temperature is typically 90°. Temperatures cover 67° across the year, low to high. Summer afternoons here are warmer than in 77% of U.S. towns. Homes need heating from November to March, the months averaging under 50°.
A year in Soap Lake at a glance
Each month’s typical high and low, and what it brings.
What stands out about Soap Lake’s climate
Compared with towns across the U.S., with Soap Lake’s place in Washington beside it.
What a year in Soap Lake feels like
Typical highs and lows by season and by month, from NOAA’s 30-year normals.
About 175 frost-free days a year
In half of years the last 32° night comes by April 22 and the first by October 17. Frost and day counts come from NOAA’s station at Ephrata Muni Airport, 6 miles from the town’s center, 140 ft higher.
The 2023 USDA map puts Soap Lake’s center in zone 7a: the coldest night of a typical winter, averaged over 1991–2020, reaches about 1°. 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 7 inches of rain a year
December is the wettest month and August the driest.
Rain + melted snow by month
Inches of water
Heating and cooling a home in Soap Lake
87% 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 Ephrata Muni Airport.
Living with Soap Lake’s climate
What the numbers mean for a garden, a free afternoon and a bad-weather day.
175 frost-free days in zone 7a. The last frost comes by Apr 22 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 17.
Months with highs of 62–84° and lows of 40° or more: May, June and September. 1.4 miles of trails are waiting.
Parks & trails →Of the yearly building losses FEMA expects in Soap Lake from natural hazards, river flooding is the largest share (61%); heat waves, cold waves, winter storms and ice storms together are 17%. Normals are averages; the hazards page covers the extremes.
Natural hazards →Soap Lake and similar climates
TownRatings has no climate map of the towns around Soap Lake yet.
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 Soap Lake averaged 1.1° warmer than the 1900s. The biggest change is in January (+4.0°).
A smaller shift than in 67% 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 Soap Lake compares
Against 12,954 U.S. towns of 2,500 or more (one per 5 km climate cell), with Soap Lake’s place among Washington’s.
Soap Lake weather by month
Highs, lows and precipitation from NOAA’s grid at Soap Lake’s center. 1991–2020 normals.
| Month | High | Low | Rain + melt | 30-yr range |
|---|---|---|---|---|
| January | 36° | 23° | 0.8" | 20° – 36° |
| February | 43° | 26° | 0.6" | 24° – 42° |
| March | 55° | 31° | 0.7" | 36° – 49° |
| April | 64° | 38° | 0.6" | 45° – 58° |
| May | 74° | 46° | 0.7" | 54° – 66° |
| June | 81° | 53° | 0.6" | 62° – 76° |
| July | 90° | 59° | 0.3" | 65° – 78° |
| August | 89° | 57° | 0.2" | 67° – 76° |
| September | 79° | 48° | 0.2" | 60° – 67° |
| October | 63° | 37° | 0.6" | 45° – 57° |
| November | 46° | 29° | 0.8" | 31° – 45° |
| December | 35° | 23° | 1.0" | 23° – 35° |
| Year | 63° | 39° | 7.2" |
How much a month can swing
A normal is an average. February swings the most: from 1991 to 2020 its average ranged from 24° to 42°. September is the most reliable, staying within 7°.
Where Soap Lake’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 Soap Lake’s center.
- Frost, freezing nights, 90° and 100° days, heating and cooling: Ephrata Muni Airport, 6 miles from the town’s center, 140 ft higher; 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 Soap Lake’s climate
What is the weather like in Soap Lake?
A typical July afternoon reaches 90°, a January night drops to 23°. Milder January nights than 55% of U.S. towns; hotter July afternoons than 77% of U.S. towns.
How cold does it get in Soap Lake in winter?
January nights average 23°. About 121 nights a year reach 32° or below and 1 reach 0° or below. In the coldest January of the last 30 years the month averaged 20°.
How hot does it get in Soap Lake?
July, with a typical high of 90° and a low of 59°. About 40 days a year reach 90° and 6 reach 100° (Ephrata Muni Airport).
When is the first and last frost in Soap Lake?
In half of years the last spring frost (32°) comes by April 22 and the first fall frost by October 17, about 175 frost-free days, at Ephrata Muni Airport.
What growing zone is Soap Lake in?
Zone 7a on the 2023 USDA Plant Hardiness Zone Map: the coldest night of a typical winter reaches about 1°.
What is the best time of year to visit Soap Lake?
By one simple rule (highs of 62–84° and lows of 40° or more), May, June and September. The rule is ours, not NOAA’s; the month table has the numbers to judge by.
Is Soap Lake getting warmer?
Yes: 1991–2020 averaged 1.1° warmer than 1901–2000 on NOAA’s grid. A smaller shift than 67% of U.S. towns.
Neighbors talk weather
Gardens, snow, and the best days of the year in Soap Lake.
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.