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Every US forecast, compared
CheckWeather US›Napa

Napa weather

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NWSNational Blend (NBM)
61°
Clear
Feels 61° · Wind 4 mph · Humidity 82%
AmericanNOAA GFS
60°
Clear
Feels 59° · Wind 5 mph · Humidity 87%
EuropeanECMWF
60°
Clear
Feels 59° · Wind 6 mph · Humidity 90%

Latest for Napa: NWS (National Blend (NBM)): 61° Clear · American (NOAA GFS): 60° Clear · European (ECMWF): 60° Clear.

The weather map: all three models at once

NWS, American, European side by side around Napa and nearby towns.Live rain radar →
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Next 14 hours

consensus of the three models

7-day forecast

where the models agree, and where they split

Napa, CA is at its warmest in Jul (average highs near 90°F) and coldest in Feb (lows around 39°F), with roughly 39 in of precipitation across the year. Below, compare what NWS, American, European forecast for Napa right now, and see exactly where they disagree.

Napa climate by month

average daytime high and overnight low across a typical year
Jan
58°
42°
Feb
58°
39°
Mar
59°
42°
Apr
68°
44°
May
74°
50°
Jun
81°
54°
Jul
90°
57°
Aug
87°
57°
Sep
82°
55°
Oct
80°
53°
Nov
65°
44°
Dec
60°
43°

Which forecast is most accurate in the US?

CheckWeather Score — graded against the weather that actually happened
ProviderCheckWeather Score🌡 Temp💨 Wind🌧 RainRun by
European logo
European ★ Best
Behind Apple Weather, Windy
88
/100rank #1
85±1.5°F96±1.2 mph8592% hitECMWF — European Centre for Medium-Range Weather ForecastsReading, United Kingdom
American logo
American
Behind Windy & many free apps
74
/100rank #2
82±1.8°F92±2.6 mph5374% 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 40 cities. Lower error means a higher score. The apps you know (AccuWeather, Apple Weather, The Weather Channel) are built on these models.

Common questions

What's the weather in Napa today?
On this page we show what NWS, American, European each forecast for Napa 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 Napa today or tomorrow?
Check the hourly strip and 7-day forecast above. We compare rain from NWS, American, European for Napa 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 Napa?
No single model is always right. NWS, American, European each run their own physics, so we line all three up: when they agree the Napa forecast is reliable, and when they split you should expect surprises. See our tested US accuracy scoreboard for how the models compare.
What is the warmest month in Napa?
July is typically the warmest month in Napa, with average highs around 90°F.
How cold does Napa get?
The coldest month in Napa is February, when overnight lows average about 39°F.
How much rain does Napa get?
Napa sees roughly 39 in of precipitation a year, with January usually the wettest month.

The forecasts Americans check

The two biggest apps keep their model a secret, so we can't show their numbers, only link you to them. The National Weather Service is public, so its data sits right in the comparison above.

NWSNational Weather Service
Open model · shown above ✓AWAccuWeather
Closed model · open ↗↗TWCThe Weather Channel
Closed model · open ↗↗

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