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CheckWeather USSan Marcos
Forecast confidence: Medium · models disagree by 6°F

San Marcos weather

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Cloudy,rain likely tomorrow

NWS, the American and the European model put San Marcos's high today between 85° and 91°, a 6° split. Tomorrow looks cloudy around 86°, with a 62% chance of rain.

88°60°
86°71°
91°71°
92°71°
94°72°
90°72°
Todaysplit ±6°Tomorrowsplit ±6°Mondaysplit ±6°Tuesdaysplit ±6°Wednesdaysplit ±6°Thursdaymodels agree
NWSNational Blend (NBM)
85°
Partly cloudy
Today 85°·Low 65°·Rain 4%
AmericanNOAA GFS
91°
Cloudy
Today 91°·Low 59°·Rain 4%
EuropeanECMWF
89°
Cloudy
Today 89°·Low 57°·Rain 30%

The weather map: all three models at once

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

Next 14 hours

consensus of the three models

14-day forecast

where the models agree, and where they split
Today
Cloudy
88° 60°
±6°
Tomorrow
Cloudy
86° 71°
±6°
Mon
Partly cloudy
91° 71°
±6°
Tue
Partly cloudy
92° 71°
±6°
Wed
Light drizzle
94° 72°
±6°
Thu
Clear
90° 72°
models agree
Fri
Mostly clear
85° 69°
models agree
Sat
Cloudy
82° 67°
models agree
Sun
Mostly clear
81° 63°
±5°
Mon
Mostly clear
81° 63°
models agree
Tue
Light drizzle
84° 63°
models agree
Wed
Light drizzle
86° 66°
models agree
Thu
Drizzle
83° 66°
±6°
Fri
Mostly clear
84° 66°
±10°

San Marcos, 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 Score🌡 Temp💨 Wind🌧 RainRun by
European logo
European ★ Best
91
/100rank #1
79±2.1°F97±1.1 mph100100% hitECMWF - European Centre for Medium-Range Weather ForecastsReading, United Kingdom
American logo
American
91
/100rank #2
81±1.9°F95±1.6 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.

Where the models disagree

temperature and rain, judged separately
DayTemperatureRain
Today±6°85° to 91°±26%4% to 30% chance
Tomorrow±6°84° to 90°±47%15% to 62% chance
Mon±6°89° to 95°±11%3% to 14% chance
Tue±6°89° to 95°±5%7% to 12% chance
Wed±6°91° to 97°±12%4% to 16% 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
06:25
Sunset
19:08
Daylight
12h 43m

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 91/100), 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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