Skip to main content
One weather site to rule them all
checkweather.io

Issaquah weather

Loading live data…

NWSNational Blend (NBM)
40°
Partly cloudy
Feels 36° · Wind 2 mph · Humidity 89%
AmericanNOAA GFS
42°
Partly cloudy
Feels 35° · Wind 6 mph · Humidity 58%
EuropeanECMWF
35°
Partly cloudy
Feels 30° · Wind 4 mph · Humidity 92%

Latest for Issaquah: NWS (National Blend (NBM)): 40° Partly cloudy · American (NOAA GFS): 42° Partly cloudy · European (ECMWF): 35° Partly cloudy.

CheckWeather.io on iPhoneFree. No ads, no account.

Issaquah weather alerts and warnings

active National Weather Service watches, warnings and advisories

Checking the National Weather Service for active alerts covering Issaquah…

Issaquah weather in numbers

measured normals and 10 years of recorded weather

Issaquah swings 44°F across the year, from 79°F highs in July to 35°F lows in December, and November is usually the wettest month in a year that brings about 66 in of precipitation. Over 10 years of recorded weather it averages 53 days a year at 77°F or above, 14 of them at 86°F or above, 37 frost nights, and rain on 172 days.

Warmest month
July
79°F average high
Coldest month
December
35°F average low
Wettest month
November
66 in a year
Comfortable
4 months
May, June, August and September
Residents
36,000
share this forecast
Most accurate here
European
98/100 CheckWeather Score
Warm days
53 days
a year at 77°F or above
Frost nights
37 nights
a year below 32°F
Rain days
172 days
a year with 0.04 in or more

Day counts are from the ERA5 reanalysis for Issaquah’s grid square, 2016 to 2025, counted the same way for every city so the numbers compare. A reanalysis square is an area, not a weather station, so it is good for counting days and not for a single day’s record.

The weather map: all three models at once

NWS, American, European side by side around Issaquah and nearby towns.Live rain radar →
Loading the three model maps…

Issaquah hourly forecast: next 14 hours

consensus of the three models

Rain in the next 24 hours, model by model

each model's own hourly precipitation, side by side

Loading the three models…

Issaquah 10-day forecast, out to 14 days

where the models agree, and where they split

Issaquah, Washington (WA) is at its warmest in Jul (average highs near 79°F) and coldest in Dec (lows around 35°F), with roughly 66 in of precipitation across the year. Below, compare what NWS, American, European forecast for Issaquah right now, and see exactly where they disagree.

We grade every model against the weather that actually happened, so you can see which forecast model is most accurate in United States before you trust any single number.

Issaquah climate by month

average daytime high and overnight low across a typical year (1991-2020)
Jan
47°
36°
Feb
48°
36°
Mar
54°
37°
Apr
57°
41°
May
65°
46°
Jun
70°
51°
Jul
79°
54°
Aug
77°
55°
Sep
71°
54°
Oct
62°
46°
Nov
52°
40°
Dec
47°
35°

Source: 1991-2020 averages, ERA5 for this place adjusted with NASA POWER.

How the weather around Issaquah has changed since 1995

Issaquah sits in the same roughly 50 km square of NASA's reanalysis as Redmond. That square shows no clear change in temperature between 1995-2004 and 2015-2024. See the full 30-year picture on the Redmond page.

Which forecast is most accurate in Issaquah?

CheckWeather Score, graded against the weather that actually happened
ProviderCheckWeather-scoreTempWindRainRun by
European logo
European ★ Best
98
/100rank #1
96±0.4°F98±0.7 mph100100% hitECMWF - European Centre for Medium-Range Weather ForecastsReading, United Kingdom
American logo
American
88
/100rank #2
84±1.6°F95±1.6 mph8994% hitNOAA / NCEP (United States)College Park, Maryland, USA

The CheckWeather Score blends temperature, wind and rain accuracy, each measured against ERA5 (the recorded weather) over the last 30 days across 1999 cities. Lower error means a higher score. See which forecast model is most accurate in United States, how we measure forecast accuracy, or which model each weather app uses.

What do you think of the forecasts?

your vote counts

The accuracy above is the measured record. This is your opinion: which forecast service do you trust most in United States? Give each 1 to 5 stars.

NWSNational Blend (NBM)
Loading ratings…
AmericanNOAA GFS
Loading ratings…
EuropeanECMWF
Loading ratings…

One vote per service. Anonymous: we store no personal data, only a one-way hash of your connection for a day to stop double votes.

Common questions

What's the weather in Issaquah today?
On this page we show what NWS, American, European each forecast for Issaquah today, side by side and updated live. When all three agree the forecast is reliable; when they split, we flag it so you know the day is genuinely less certain.
Will it rain in Issaquah today or tomorrow?
Check the hourly strip and 7-day forecast above. We compare rain from NWS, American, European for Issaquah and flag the days where the models disagree on whether showers actually arrive, which is exactly when a single app can catch you out.
Which forecast is most accurate for Issaquah?
Over the last 30 days, the European model has been the most accurate for Issaquah (CheckWeather Score 98/100), ahead of the American at 88. We grade every model against the recorded weather. See the US accuracy scoreboard for the full method.
What is the warmest month in Issaquah?
July is typically the warmest month in Issaquah, with average highs around 79°F.
How cold does Issaquah get?
The coldest month in Issaquah is December, when overnight lows average about 35°F.
How much rain does Issaquah get?
Issaquah sees roughly 66 in of precipitation a year, with November usually the wettest month.

Nearby

More US weather