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Forecast confidence: Medium · models disagree by 5°F

Fountain Valley weather

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Clear,much the same tomorrow

NWS, the American and the European model put Fountain Valley's high today between 74° and 79°, a 5° split. Tomorrow: mostly clear, around 78°, with a 0% chance of rain.

76°56°
78°58°
77°62°
74°61°
73°61°
72°63°
Todaysplit ±5°Tomorrowmodels agreeMondaysplit ±6°Tuesdaysplit ±6°Wednesdaysplit ±7°Thursdaysplit ±5°
NWSNational Blend (NBM)
58°
Clear
Feels 59° · Wind 2 mph · Humidity 98%
AmericanNOAA GFS
58°
Clear
Feels 57° · Wind 4 mph · Humidity 85%
EuropeanECMWF
57°
Clear
Feels 58° · Wind 2 mph · Humidity 94%

Latest for Fountain Valley: NWS (National Blend (NBM)): 58° Clear · American (NOAA GFS): 58° Clear · European (ECMWF): 57° Clear.

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Fountain Valley weather alerts and warnings

active National Weather Service watches, warnings and advisories

Checking the National Weather Service for active alerts covering Fountain Valley…

Fountain Valley weather in numbers

measured normals and 10 years of recorded weather

Fountain Valley swings 31°F across the year, from 79°F highs in September to 48°F lows in January, and February is usually the wettest month in a year that brings about 12 in of precipitation. Over 10 years of recorded weather it averages 84 days a year at 77°F or above, 9 of them at 86°F or above, 0 frost nights, and rain on 33 days.

Warmest month
September
79°F average high
Coldest month
January
48°F average low
Wettest month
February
12 in a year
Comfortable
4 months
January, March, April and May
Residents
57,000
share this forecast
Most accurate here
European
94/100 CheckWeather Score
Warm days
84 days
a year at 77°F or above
Frost nights
0 nights
a year below 32°F
Rain days
33 days
a year with 0.04 in or more

Day counts are from the ERA5 reanalysis for Fountain Valley’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 Fountain Valley and nearby towns.Live rain radar →
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Fountain Valley 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

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Fountain Valley 10-day forecast, out to 14 days

where the models agree, and where they split
Today
Clear
76° 56°
±5°
Tomorrow
Mostly clear
78° 58°
models agree
Mon
Mostly clear
77° 62°
±6°
Tue
Cloudy
74° 61°
±6°
Wed
Cloudy
73° 61°
±7°
Thu
Cloudy
72° 63°
±5°
Fri
Drizzle
70° 62°
models agree
Sat
Light rain
69° 62°
models agree
Sun
Light rain
71° 62°
±5°
Mon
Drizzle
72° 62°
±8°
Tue
Light drizzle
72° 63°
models agree
Wed
Light drizzle
72° 62°
models agree
Thu
Cloudy
72° 65°
models agree

Fountain Valley, California (CA) is at its warmest in Sep (average highs near 79°F) and coldest in Jan (lows around 48°F), with roughly 12 in of precipitation across the year. Below, compare what NWS, American, European forecast for Fountain Valley 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.

Fountain Valley climate by month

average daytime high and overnight low across a typical year (1991-2020)
Jan
63°
48°
Feb
62°
48°
Mar
64°
51°
Apr
69°
53°
May
70°
58°
Jun
73°
60°
Jul
78°
61°
Aug
78°
62°
Sep
79°
63°
Oct
75°
57°
Nov
70°
51°
Dec
65°
48°

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

How the weather around Fountain Valley has changed since 1995

Fountain Valley sits in the same roughly 50 km square of NASA's reanalysis as Santa Ana. That square ran 1.1°F warmer in 2015-2024 than in 1995-2004. See the full 30-year picture on the Santa Ana page.

Which forecast is most accurate in Fountain Valley?

CheckWeather Score, graded against the weather that actually happened
ProviderCheckWeather-scoreTempWindRainRun by
European logo
European ★ Best
94
/100rank #1
91±0.9°F98±0.6 mph9597% hitECMWF - European Centre for Medium-Range Weather ForecastsReading, United Kingdom
American logo
American
87
/100rank #2
71±2.9°F95±1.7 mph100100% 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)
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AmericanNOAA GFS
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EuropeanECMWF
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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.

Where the models disagree

temperature and rain, judged separately
DayTemperatureRain
Today±5°74° to 79°±2%0% to 2% chance
Tomorrow±2°77° to 79°models agree0% to 0% chance
Mon±6°73° to 79°models agree0% to 0% chance
Tue±6°71° to 77°models agree0% to 0% chance
Wed±7°69° to 76°models agree0% to 0% chance

The models often agree on temperature and still split on rain, and rain is usually what decides whether a plan survives. A wide rain range means the shower is genuinely uncertain, not that the forecast is wrong.

Sunrise and sunset in Fountain Valley

today, local time
Sunrise
07:04
Sunset
18:07
Daylight
11h 3m

Common questions

What's the weather in Fountain Valley today?
Saturday, October 24: NWS, the American and the European model put Fountain Valley's high today between 74° and 79°, a 5° split. Tomorrow: mostly clear, around 78°, with a 0% chance of rain. The forecast on this page refreshes live.
Will it rain in Fountain Valley today or tomorrow?
Rain looks unlikely in Fountain Valley on Sunday, October 25: no model gives more than 0% (NWS 0%, American 0%, European 0%). On Saturday, October 24 the highest chance of rain from any model is 2%. The hourly strip and the model-by-model rain panel above update live.
Which forecast is most accurate for Fountain Valley?
Over the last 30 days, the European model has been the most accurate for Fountain Valley (CheckWeather Score 94/100), ahead of the American at 87. We grade every model against the recorded weather. See the US accuracy scoreboard for the full method.
What is the warmest month in Fountain Valley?
September is typically the warmest month in Fountain Valley, with average highs around 79°F.
How cold does Fountain Valley get?
The coldest month in Fountain Valley is January, when overnight lows average about 48°F.
How much rain does Fountain Valley get?
Fountain Valley sees roughly 12 in of precipitation a year, with February usually the wettest month.

Nearby

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