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CheckWeather USPotomac
Forecast confidence: Medium · models disagree by 5°F

Potomac weather

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Partly cloudy,cooler tomorrow

NWS, the American and the European model put Potomac's high today between 82° and 86°, a 5° split. Tomorrow looks cloudy around 79°, with a 5% chance of rain.

84°71°
79°62°
83°68°
71°61°
64°59°
61°55°
Todaysplit ±5°Tomorrowmodels agreeSundaysplit ±6°Mondaysplit ±5°Tuesdaysplit ±4°Wednesdaymodels agree
NWSNational Blend (NBM)
82°
Partly cloudy
Today 82°·Low 70°·Rain 9%
AmericanNOAA GFS
84°
Cloudy
Today 84°·Low 71°·Rain 9%
EuropeanECMWF
86°
Drizzle
Today 86°·Low 72°·Rain 83%
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Potomac weather alerts and warnings

active National Weather Service watches, warnings and advisories

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Potomac weather in numbers

from 30 years of measured normals

Potomac swings 56°F across the year, from 89°F highs in July to 33°F lows in January, and December is usually the wettest month in a year that brings about 46 in of precipitation.

Warmest month
July
89°F average high
Coldest month
January
33°F average low
Wettest month
December
46 in a year
Below freezing
Never
overnight lows stay above 32°F
Comfortable
4 months
April, May, September and October
Residents
45,000
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The weather map: all three models at once

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

where the models agree, and where they split
Today
Partly cloudy
84° 71°
±5°
Tomorrow
Cloudy
79° 62°
models agree
Sun
Drizzle
83° 68°
±6°
Mon
Light rain
71° 61°
±5°
Tue
Heavy drizzle
64° 59°
±4°
Wed
Heavy drizzle
61° 55°
models agree
Thu
Heavy drizzle
63° 56°
±6°
Fri
Drizzle
70° 56°
±8°
Sat
Light drizzle
71° 52°
models agree
Sun
Light drizzle
72° 52°
±5°
Mon
Light drizzle
74° 56°
models agree
Tue
Light drizzle
76° 56°
models agree
Wed
Light rain
72° 59°
±7°
Thu
Clear
71° 52°
±7°

Potomac, Maryland (MD) is at its warmest in Jul (average highs near 89°F) and coldest in Jan (lows around 33°F), with roughly 46 in of precipitation across the year. Below, compare what NWS, American, European forecast for Potomac 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.

Potomac climate by month

average daytime high and overnight low across a typical year
Jan
47°
33°
Feb
51°
34°
Mar
56°
38°
Apr
69°
48°
May
74°
54°
Jun
84°
63°
Jul
89°
70°
Aug
85°
67°
Sep
78°
61°
Oct
69°
51°
Nov
57°
41°
Dec
48°
34°

Which forecast is most accurate in Potomac?

CheckWeather Score, graded against the weather that actually happened
ProviderCheckWeather-scoreTempWindRainRun by
European logo
European ★ Best
89
/100rank #1
90±1.0°F98±0.7 mph8290% hitECMWF - European Centre for Medium-Range Weather ForecastsReading, United Kingdom
American logo
American
68
/100rank #2
84±1.6°F95±1.5 mph2961% 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°82° to 86°±74%9% to 83% chance
Tomorrow±2°77° to 79°±3%2% to 5% chance
Sun±6°81° to 86°±14%53% to 67% chance
Mon±5°69° to 74°±11%53% to 64% chance
Tue±4°62° to 66°±8%43% to 51% 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 Potomac

today, local time
Sunrise
06:52
Sunset
19:12
Daylight
12h 20m

Common questions

What's the weather in Potomac today?
On this page we show what NWS, American, European each forecast for Potomac 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 Potomac today or tomorrow?
Check the hourly strip and 7-day forecast above. We compare rain from NWS, American, European for Potomac 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 Potomac?
Over the last 30 days, the European model has been the most accurate for Potomac (CheckWeather Score 89/100), ahead of the American at 68. We grade every model against the recorded weather. See the US accuracy scoreboard for the full method.
What is the warmest month in Potomac?
July is typically the warmest month in Potomac, with average highs around 89°F.
How cold does Potomac get?
The coldest month in Potomac is January, when overnight lows average about 33°F.
How much rain does Potomac get?
Potomac sees roughly 46 in of precipitation a year, with December usually the wettest month.

Nearby

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