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CheckWeather US›Georgia›Alpharetta
Forecast confidence: High · models disagree by 1°F

Alpharetta weather

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Clear,much the same tomorrow

NWS, the American and the European model agree on a high near 68° in Alpharetta today. Tomorrow: mostly clear, around 68°, with a 0% chance of rain.

68°48°
68°48°
71°49°
74°48°
70°50°
73°51°
Todaymodels agreeTomorrowmodels agreeMondaymodels agreeTuesdaymodels agreeWednesdaymodels agreeThursdaymodels agree
NWSNational Blend (NBM)
68°
Clear
Today 68°·Low 47°·Rain 0%
AmericanNOAA GFS
69°
Cloudy
Today 69°·Low 47°·Rain 0%
EuropeanECMWF
68°
Clear
Today 68°·Low 50°·Rain 0%
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Alpharetta weather alerts and warnings

active National Weather Service watches, warnings and advisories

Checking the National Weather Service for active alerts covering Alpharetta…

Alpharetta weather in numbers

measured normals and 10 years of recorded weather

Alpharetta swings 54°F across the year, from 87°F highs in July to 33°F lows in January, and March is usually the wettest month in a year that brings about 56 in of precipitation. Over 10 years of recorded weather it averages 153 days a year at 77°F or above, 61 of them at 86°F or above, 33 frost nights, and rain on 142 days.

Warmest month
July
87°F average high
Coldest month
January
33°F average low
Wettest month
March
56 in a year
Comfortable
3 months
April, May and October
Residents
64,000
share this forecast
Most accurate here
European
97/100 CheckWeather Score
Warm days
153 days
a year at 77°F or above
Frost nights
33 nights
a year below 32°F
Rain days
142 days
a year with 0.04 in or more

Day counts are from the ERA5 reanalysis for Alpharetta’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 Alpharetta and nearby towns.Live rain radar →
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Alpharetta 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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Alpharetta 10-day forecast, out to 14 days

where the models agree, and where they split
Today
Clear
68° 48°
models agree
Tomorrow
Mostly clear
68° 48°
models agree
Mon
Mostly clear
71° 49°
models agree
Tue
Mostly clear
74° 48°
models agree
Wed
Cloudy
70° 50°
models agree
Thu
Mostly clear
73° 51°
models agree
Fri
Mostly clear
76° 52°
models agree
Sat
Cloudy
75° 55°
models agree
Sun
Light drizzle
72° 58°
±7°
Mon
Light rain
71° 54°
models agree
Tue
Partly cloudy
68° 47°
models agree
Wed
Cloudy
67° 48°
models agree
Thu
Cloudy
69° 50°
±9°

Alpharetta, Georgia (GA) is at its warmest in Jul (average highs near 87°F) and coldest in Jan (lows around 33°F), with roughly 56 in of precipitation across the year. Below, compare what NWS, American, European forecast for Alpharetta 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.

Alpharetta climate by month

average daytime high and overnight low across a typical year (1991-2020)
Jan
50°
33°
Feb
55°
36°
Mar
62°
42°
Apr
70°
50°
May
78°
59°
Jun
86°
65°
Jul
87°
68°
Aug
87°
67°
Sep
81°
63°
Oct
73°
52°
Nov
59°
43°
Dec
53°
37°

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

How the weather around Alpharetta has changed since 1995

Alpharetta sits in the same roughly 50 km square of NASA's reanalysis as Sandy Springs. That square ran 1.7°F warmer in 2015-2024 than in 1995-2004. See the full 30-year picture on the Sandy Springs page.

Which forecast is most accurate in Alpharetta?

CheckWeather Score, graded against the weather that actually happened
ProviderCheckWeather-scoreTempWindRainRun by
European logo
European ★ Best
97
/100rank #1
95±0.5°F97±1.0 mph100100% hitECMWF - European Centre for Medium-Range Weather ForecastsReading, United Kingdom
American logo
American
75
/100rank #2
87±1.3°F96±1.2 mph4771% 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°68° to 69°models agree0% to 0% chance
Tomorrow±1°67° to 68°models agree0% to 0% chance
Mon±3°70° to 73°models agree0% to 0% chance
Tue±4°73° to 77°models agree0% to 0% chance
Wed±1°69° to 70°±1%1% to 2% 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 Alpharetta

today, local time
Sunrise
07:49
Sunset
18:52
Daylight
11h 3m

Common questions

What's the weather in Alpharetta today?
Saturday, October 24: NWS, the American and the European model agree on a high near 68° in Alpharetta today. Tomorrow: mostly clear, around 68°, with a 0% chance of rain. The forecast on this page refreshes live.
Will it rain in Alpharetta today or tomorrow?
Rain looks unlikely in Alpharetta 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 0%. The hourly strip and the model-by-model rain panel above update live.
Which forecast is most accurate for Alpharetta?
Over the last 30 days, the European model has been the most accurate for Alpharetta (CheckWeather Score 97/100), ahead of the American at 75. We grade every model against the recorded weather. See the US accuracy scoreboard for the full method.
What is the warmest month in Alpharetta?
July is typically the warmest month in Alpharetta, with average highs around 87°F.
How cold does Alpharetta get?
The coldest month in Alpharetta is January, when overnight lows average about 33°F.
How much rain does Alpharetta get?
Alpharetta sees roughly 56 in of precipitation a year, with March usually the wettest month.

Nearby

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