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Forecast confidence: High · models disagree by 1°F

San Marcos weather

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Partly cloudy,much the same tomorrow

NWS, the American and the European model agree on a high near 78° in San Marcos today. Tomorrow looks cloudy around 79°, with a 0% chance of rain.

78°62°
79°61°
77°61°
76°62°
77°59°
80°61°
Todaymodels agreeTomorrowmodels agreeSundaymodels agreeMondaymodels agreeTuesdaymodels agreeWednesdaysplit ±5°
NWSNational Blend (NBM)
77°
Partly cloudy
Today 77°·Low 64°·Rain 0%
AmericanNOAA GFS
78°
Cloudy
Today 78°·Low 63°·Rain 0%
EuropeanECMWF
78°
Partly cloudy
Today 78°·Low 59°·Rain 0%
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San Marcos weather alerts and warnings

active National Weather Service watches, warnings and advisories

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San Marcos weather in numbers

from 30 years of measured normals

San Marcos swings 42°F across the year, from 84°F highs in July to 42°F lows in January, and January is usually the wettest month in a year that brings about 24 in of precipitation.

Warmest month
July
84°F average high
Coldest month
January
42°F average low
Wettest month
January
24 in a year
Below freezing
Never
overnight lows stay above 32°F
Comfortable
4 months
February, March, April and May
Residents
93,000
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The weather map: all three models at once

NWS, American, European side by side around San Marcos and nearby towns.Live rain radar →
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San Marcos 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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San Marcos 10-day forecast, out to 14 days

where the models agree, and where they split
Today
Partly cloudy
78° 62°
models agree
Tomorrow
Cloudy
79° 61°
models agree
Sun
Partly cloudy
77° 61°
models agree
Mon
Partly cloudy
76° 62°
models agree
Tue
Clear
77° 59°
models agree
Wed
Mostly clear
80° 61°
±5°
Thu
Partly cloudy
81° 63°
±5°
Fri
Mostly clear
82° 65°
±9°
Sat
Cloudy
84° 64°
±11°
Sun
Partly cloudy
87° 67°
±7°
Mon
Cloudy
88° 69°
±11°
Tue
Cloudy
89° 69°
models agree
Wed
Clear
76° 65°
±10°
Thu
Clear
74° 63°
±7°

San Marcos, California (CA) is at its warmest in Jul (average highs near 84°F) and coldest in Jan (lows around 42°F), with roughly 24 in of precipitation across the year. Below, compare what NWS, American, European forecast for San Marcos 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.

San Marcos climate by month

average daytime high and overnight low across a typical year
Jan
61°
42°
Feb
60°
42°
Mar
61°
45°
Apr
66°
48°
May
68°
53°
Jun
75°
57°
Jul
84°
62°
Aug
84°
63°
Sep
80°
62°
Oct
80°
56°
Nov
72°
48°
Dec
68°
46°

Which forecast is most accurate in San Marcos?

CheckWeather Score, graded against the weather that actually happened
ProviderCheckWeather-scoreTempWindRainRun by
European logo
European ★ Best
92
/100rank #1
82±1.8°F97±0.9 mph100100% hitECMWF - European Centre for Medium-Range Weather ForecastsReading, United Kingdom
American logo
American
91
/100rank #2
80±2.0°F95±1.5 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±1°77° to 78°models agree0% to 0% chance
Tomorrow±1°78° to 79°models agree0% to 0% chance
Sun±2°77° to 78°models agree0% to 0% chance
Mon±2°75° to 77°±3%3% to 6% chance
Tue±1°76° to 78°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 San Marcos

today, local time
Sunrise
06:34
Sunset
18:50
Daylight
12h 16m

Common questions

What's the weather in San Marcos today?
On this page we show what NWS, American, European each forecast for San Marcos 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 San Marcos today or tomorrow?
Check the hourly strip and 7-day forecast above. We compare rain from NWS, American, European for San Marcos 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 San Marcos?
Over the last 30 days, the European model has been the most accurate for San Marcos (CheckWeather Score 92/100), ahead of the American at 91. We grade every model against the recorded weather. See the US accuracy scoreboard for the full method.
What is the warmest month in San Marcos?
July is typically the warmest month in San Marcos, with average highs around 84°F.
How cold does San Marcos get?
The coldest month in San Marcos is January, when overnight lows average about 42°F.
How much rain does San Marcos get?
San Marcos sees roughly 24 in of precipitation a year, with January usually the wettest month.

Nearby

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