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Forecast confidence: High · models disagree by 2°C

Grantham weather

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Rain,rain likely tomorrow

Met Office, the European and the American model agree on a high near 15° in Grantham today. Tomorrow: cloudy, around 11°, with a 56% chance of rain.

15°6°
11°8°
16°7°
16°9°
14°8°
12°8°
Todaymodels agreeTomorrowmodels agreeMondaymodels agreeTuesdaymodels agreeWednesdaymodels agreeThursdaysplit ±3°
Met OfficeUKMO model
10°
Heavy drizzle
Feels 5° · Wind 17 mph · Humidity 89%
EuropeanECMWF
10°
Light rain
Feels 5° · Wind 20 mph · Humidity 90%
AmericanNOAA GFS
10°
Light drizzle
Feels 4° · Wind 22 mph · Humidity 85%

Latest for Grantham: Met Office (UKMO model): 10° Heavy drizzle · European (ECMWF): 10° Light rain · American (NOAA GFS): 10° Light drizzle.

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Grantham weather warnings

Met Office yellow, amber and red warnings for East Midlands

Checking the Met Office for warnings in force for East Midlands…

Grantham weather in numbers

measured normals and 10 years of recorded weather

Grantham swings 20°C across the year, from 21°C highs in August to 1°C lows in February, and August is usually the wettest month in a year that brings about 645 mm of precipitation. Over 10 years of recorded weather it averages 13 days a year at 25°C or above, 1 of them at 30°C or above, 30 frost nights, and rain on 139 days.

Warmest month
August
21°C average high
Coldest month
February
1°C average low
Wettest month
August
645 mm a year
Comfortable
4 months
May, June, July and September
Residents
45,000
share this forecast
Most accurate here
European
94/100 CheckWeather Score
Warm days
13 days
a year at 25°C or above
Frost nights
30 nights
a year below 0°C
Rain days
139 days
a year with 1 mm or more

Day counts are from the ERA5 reanalysis for Grantham’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

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

where the models agree, and where they split
Today
Rain
15° 6°
models agree
Tomorrow
Cloudy
11° 8°
models agree
Mon
Light rain
16° 7°
models agree
Tue
Light drizzle
16° 9°
models agree
Wed
Cloudy
14° 8°
models agree
Thu
Fog
12° 8°
±3°
Fri
Light drizzle
14° 8°
models agree
Sat
Light rain
12° 6°
models agree
Sun
Light drizzle
11° 6°
models agree
Mon
Light drizzle
10° 5°
models agree
Tue
Light drizzle
10° 6°
models agree
Wed
Light drizzle
8° 2°
models agree
Thu
Cloudy
7° 2°
±3°
Fri
Light drizzle
8° 1°
±3°

Grantham, England is at its warmest in Aug (average highs near 21°C) and coldest in Feb (lows around 1°C), with roughly 645 mm of precipitation across the year. Below, compare what Met Office, European, American forecast for Grantham 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 Kingdom before you trust any single number.

Grantham climate by month

average daytime high and overnight low across a typical year (1991-2020)
Jan
7°
2°
Feb
7°
1°
Mar
9°
3°
Apr
12°
5°
May
16°
8°
Jun
19°
10°
Jul
20°
12°
Aug
21°
13°
Sep
17°
9°
Oct
14°
8°
Nov
9°
4°
Dec
7°
3°

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

How the weather around Grantham has changed since 1995

Grantham sits in the same roughly 50 km square of NASA's reanalysis as Lincoln. That square ran 0.5°C warmer in 2015-2024 than in 1995-2004. See the full 30-year picture on the Lincoln page.

Which forecast is most accurate in Grantham?

CheckWeather Score, graded against the weather that actually happened
ProviderCheckWeather-scoreTempWindRainRun by
European logo
European ★ Best
94
/100rank #1
96±0.2°C97±1.0 mph8994% hitECMWF - European Centre for Medium-Range Weather ForecastsReading, United Kingdom
Met Office logo
Met Office
81
/100rank #2
92±0.5°C96±1.1 mph5877% hitMet Office (United Kingdom)Exeter, United Kingdom
American logo
American
77
/100rank #3
82±1.0°C94±1.9 mph5877% 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 1950 cities. Lower error means a higher score. See which forecast model is most accurate in United Kingdom, 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 Kingdom? Give each 1 to 5 stars.

Met OfficeUKMO model
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EuropeanECMWF
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AmericanNOAA GFS
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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±2°14° to 16°models agree100% to 100% chance
Tomorrow±1°11° to 12°±23%33% to 56% chance
Mon±1°15° to 16°±9%91% to 100% chance
Tuemodels agree16° to 16°±51%49% to 100% chance
Wed±2°13° to 15°±64%3% to 67% 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 Grantham

today, local time
Sunrise
07:45
Sunset
17:47
Daylight
10h 2m

Common questions

What's the weather in Grantham today?
Saturday 24 October: Met Office, the European and the American model agree on a high near 15° in Grantham today. Tomorrow: cloudy, around 11°, with a 56% chance of rain. The forecast on this page refreshes live.
Will it rain in Grantham today or tomorrow?
The models split on rain in Grantham on Sunday 25 October: Met Office 33%, European 41%, American 56%. When they disagree like this, treat any single app's answer with caution. On Saturday 24 October the highest chance of rain from any model is 100%. The hourly strip and the model-by-model rain panel above update live.
Which forecast is most accurate for Grantham?
Over the last 30 days, the European model has been the most accurate for Grantham (CheckWeather Score 94/100), ahead of the Met Office at 81. We grade every model against the recorded weather. See the UK accuracy scoreboard for the full method.
What is the warmest month in Grantham?
August is typically the warmest month in Grantham, with average highs around 21°C.
How cold does Grantham get?
The coldest month in Grantham is February, when overnight lows average about 1°C.
How much rain does Grantham get?
Grantham sees roughly 645 mm of precipitation a year, with August usually the wettest month.

Nearby

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