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Forecast confidence: High · models disagree by 3°F

Janesville weather

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Cloudy,much the same tomorrow

NWS, the American and the European model agree on a high near 70° in Janesville today. Tomorrow: cloudy, around 71°, with a 14% chance of rain.

70°49°
71°51°
62°48°
65°47°
70°53°
68°52°
Todaymodels agreeTomorrowmodels agreeMondaymodels agreeTuesdaymodels agreeWednesdaymodels agreeThursdaysplit ±5°
NWSNational Blend (NBM)
51°
Partly cloudy
Feels 47° · Wind 6 mph · Humidity 79%
AmericanNOAA GFS
47°
Partly cloudy
Feels 44° · Wind 4 mph · Humidity 88%
EuropeanECMWF
53°
Overcast
Feels 48° · Wind 8 mph · Humidity 73%

Latest for Janesville: NWS (National Blend (NBM)): 51° Partly cloudy · American (NOAA GFS): 47° Partly cloudy · European (ECMWF): 53° Overcast.

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Janesville weather alerts and warnings

active National Weather Service watches, warnings and advisories

Checking the National Weather Service for active alerts covering Janesville…

Janesville weather in numbers

measured normals and 10 years of recorded weather

Janesville swings 68°F across the year, from 82°F highs in July to 14°F lows in January, and June is usually the wettest month in a year that brings about 36 in of precipitation. Over 10 years of recorded weather it averages 91 days a year at 77°F or above, 22 of them at 86°F or above, 130 frost nights, and rain on 119 days.

Warmest month
July
82°F average high
Coldest month
January
14°F average low
Wettest month
June
36 in a year
Comfortable
2 months
May and September
Residents
64,000
share this forecast
Most accurate here
European
97/100 CheckWeather Score
Warm days
91 days
a year at 77°F or above
Frost nights
130 nights
a year below 32°F
Rain days
119 days
a year with 0.04 in or more

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

where the models agree, and where they split
Today
Cloudy
70° 49°
models agree
Tomorrow
Cloudy
71° 51°
models agree
Mon
Cloudy
62° 48°
models agree
Tue
Cloudy
65° 47°
models agree
Wed
Cloudy
70° 53°
models agree
Thu
Partly cloudy
68° 52°
±5°
Fri
Partly cloudy
69° 51°
±7°
Sat
Light drizzle
68° 54°
±9°
Sun
Light drizzle
63° 50°
±8°
Mon
Drizzle
59° 41°
±8°
Tue
Cloudy
45° 39°
models agree
Wed
Cloudy
52° 39°
models agree
Thu
Cloudy
56° 38°
±13°

Janesville, Wisconsin (WI) is at its warmest in Jul (average highs near 82°F) and coldest in Jan (lows around 14°F), with roughly 36 in of precipitation across the year. Below, compare what NWS, American, European forecast for Janesville 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.

Janesville climate by month

average daytime high and overnight low across a typical year (1991-2020)
Jan
26°
14°
Feb
35°
15°
Mar
45°
27°
Apr
56°
37°
May
70°
48°
Jun
79°
59°
Jul
82°
63°
Aug
80°
61°
Sep
72°
54°
Oct
59°
42°
Nov
45°
31°
Dec
32°
21°

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

How Janesville's weather has changed since 1995

30 years of daily data, 1995-2024, shown as change
+0.9°F

Around Janesville, the difference between 1995-2004 and 2015-2024 is +0.9°F, within the normal swing from year to year.

1995: −1.8°F vs the 30-year average1996: −3.4°F vs the 30-year average1997: −1.6°F vs the 30-year average1998: +2.5°F vs the 30-year average1999: +0.6°F vs the 30-year average2000: −0.5°F vs the 30-year average2001: +0.7°F vs the 30-year average2002: +0.7°F vs the 30-year average2003: −0.3°F vs the 30-year average2004: ±0.0°F vs the 30-year average2005: +1.6°F vs the 30-year average2006: +1.3°F vs the 30-year average2007: +0.2°F vs the 30-year average2008: −2.5°F vs the 30-year average2009: −2.1°F vs the 30-year average2010: +0.4°F vs the 30-year average2011: ±0.0°F vs the 30-year average2012: +3.6°F vs the 30-year average2013: −1.8°F vs the 30-year average2014: −3.8°F vs the 30-year average2015: +0.4°F vs the 30-year average2016: +1.5°F vs the 30-year average2017: +0.6°F vs the 30-year average2018: −0.9°F vs the 30-year average2019: −1.8°F vs the 30-year average2020: ±0.0°F vs the 30-year average2021: +2.0°F vs the 30-year average2022: −0.7°F vs the 30-year average2023: +2.2°F vs the 30-year average2024: +2.9°F vs the 30-year average
1995each stripe is one year2024
cooler than averagearound averagewarmer than average

Days above 86°F

3 fewer days a year

2015-2024 against 1995-2004. Within the normal year-to-year swing

1995: +7 vs the 30-year average1996: −15 vs the 30-year average1997: −2 vs the 30-year average1998: −3 vs the 30-year average1999: −2 vs the 30-year average2000: −7 vs the 30-year average2001: +8 vs the 30-year average2002: +14 vs the 30-year average2003: +22 vs the 30-year average2004: −15 vs the 30-year average2005: +41 vs the 30-year average2006: +8 vs the 30-year average2007: −4 vs the 30-year average2008: −15 vs the 30-year average2009: −12 vs the 30-year average2010: −15 vs the 30-year average2011: −5 vs the 30-year average2012: +43 vs the 30-year average2013: −7 vs the 30-year average2014: −15 vs the 30-year average2015: −4 vs the 30-year average2016: −7 vs the 30-year average2017: −10 vs the 30-year average2018: −6 vs the 30-year average2019: −11 vs the 30-year average2020: −9 vs the 30-year average2021: +22 vs the 30-year average2022: −2 vs the 30-year average2023: +7 vs the 30-year average2024: +2 vs the 30-year average

Frost nights

1 fewer night a year

2015-2024 against 1995-2004, below 32°F. Within the normal year-to-year swing

1995: +9 vs the 30-year average1996: +24 vs the 30-year average1997: +15 vs the 30-year average1998: −20 vs the 30-year average1999: −8 vs the 30-year average2000: −4 vs the 30-year average2001: −10 vs the 30-year average2002: +15 vs the 30-year average2003: −3 vs the 30-year average2004: −5 vs the 30-year average2005: −4 vs the 30-year average2006: +2 vs the 30-year average2007: −6 vs the 30-year average2008: +11 vs the 30-year average2009: −5 vs the 30-year average2010: −10 vs the 30-year average2011: −3 vs the 30-year average2012: −13 vs the 30-year average2013: +16 vs the 30-year average2014: +9 vs the 30-year average2015: −10 vs the 30-year average2016: −15 vs the 30-year average2017: −9 vs the 30-year average2018: +28 vs the 30-year average2019: +12 vs the 30-year average2020: +13 vs the 30-year average2021: −6 vs the 30-year average2022: +12 vs the 30-year average2023: −1 vs the 30-year average2024: −22 vs the 30-year average

Average wind

−2%

2015-2024 against 1995-2004. Within the normal year-to-year swing

1995: +2% vs the 30-year average1996: +2% vs the 30-year average1997: +2% vs the 30-year average1998: −5% vs the 30-year average1999: +2% vs the 30-year average2000: −1% vs the 30-year average2001: −1% vs the 30-year average2002: +2% vs the 30-year average2003: +4% vs the 30-year average2004: +4% vs the 30-year average2005: −3% vs the 30-year average2006: +2% vs the 30-year average2007: +4% vs the 30-year average2008: +4% vs the 30-year average2009: −1% vs the 30-year average2010: −5% vs the 30-year average2011: −1% vs the 30-year average2012: −1% vs the 30-year average2013: −1% vs the 30-year average2014: +2% vs the 30-year average2015: +2% vs the 30-year average2016: −3% vs the 30-year average2017: +2% vs the 30-year average2018: −5% vs the 30-year average2019: −3% vs the 30-year average2020: −1% vs the 30-year average2021: −3% vs the 30-year average2022: +6% vs the 30-year average2023: −5% vs the 30-year average2024: −1% vs the 30-year average

Bars: each year against the area's 30-year average. Dashed lines: the average of the first and the last ten years.

See the numbers year by year
YearTemp vs averageDays >86°F vs avgFrost nights vs avgWind vs avg
1995−1.8°F+7+9+2%
1996−3.4°F−15+24+2%
1997−1.6°F−2+15+2%
1998+2.5°F−3−20−5%
1999+0.6°F−2−8+2%
2000−0.5°F−7−4−1%
2001+0.7°F+8−10−1%
2002+0.7°F+14+15+2%
2003−0.3°F+22−3+4%
2004±0.0°F−15−5+4%
2005+1.6°F+41−4−3%
2006+1.3°F+8+2+2%
2007+0.2°F−4−6+4%
2008−2.5°F−15+11+4%
2009−2.1°F−12−5−1%
2010+0.4°F−15−10−5%
2011±0.0°F−5−3−1%
2012+3.6°F+43−13−1%
2013−1.8°F−7+16−1%
2014−3.8°F−15+9+2%
2015+0.4°F−4−10+2%
2016+1.5°F−7−15−3%
2017+0.6°F−10−9+2%
2018−0.9°F−6+28−5%
2019−1.8°F−11+12−3%
2020±0.0°F−9+13−1%
2021+2.0°F+22−6−3%
2022−0.7°F−2+12+6%
2023+2.2°F+7−1−5%
2024+2.9°F+2−22−1%

Source: NASA POWER daily data from the MERRA-2 reanalysis, 1995-2024. Each value describes a grid square of about 50 km around Janesville, not a weather station, and a square that takes in sea or a large lake runs milder than the city itself. That is why this section shows change against the square's own 30-year average rather than counts you could compare with a local station. Rain and snow are left out because their long-term record in this dataset is not consistent over time. "Within the normal year-to-year swing" means the change is smaller than the usual differences between single years.

Which forecast is most accurate in Janesville?

CheckWeather Score, graded against the weather that actually happened
ProviderCheckWeather-scoreTempWindRainRun by
European logo
European ★ Best
97
/100rank #1
97±0.3°F98±0.5 mph9597% hitECMWF - European Centre for Medium-Range Weather ForecastsReading, United Kingdom
American logo
American
85
/100rank #2
87±1.3°F95±1.5 mph7687% 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±3°68° to 71°±8%3% to 11% chance
Tomorrow±4°69° to 73°±10%4% to 14% chance
Mon±4°60° to 64°±9%1% to 10% chance
Tue±1°64° to 66°±34%3% to 37% chance
Wed±2°69° to 70°±13%11% to 24% 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 Janesville

today, local time
Sunrise
07:20
Sunset
17:59
Daylight
10h 39m

Common questions

What's the weather in Janesville today?
Saturday, October 24: NWS, the American and the European model agree on a high near 70° in Janesville today. Tomorrow: cloudy, around 71°, with a 14% chance of rain. The forecast on this page refreshes live.
Will it rain in Janesville today or tomorrow?
Rain looks unlikely in Janesville on Sunday, October 25: no model gives more than 14% (NWS 4%, American 4%, European 14%). On Saturday, October 24 the highest chance of rain from any model is 11%. The hourly strip and the model-by-model rain panel above update live.
Which forecast is most accurate for Janesville?
Over the last 30 days, the European model has been the most accurate for Janesville (CheckWeather Score 97/100), ahead of the American at 85. We grade every model against the recorded weather. See the US accuracy scoreboard for the full method.
What is the warmest month in Janesville?
July is typically the warmest month in Janesville, with average highs around 82°F.
How cold does Janesville get?
The coldest month in Janesville is January, when overnight lows average about 14°F.
How much rain does Janesville get?
Janesville sees roughly 36 in of precipitation a year, with June usually the wettest month.
Is Janesville getting warmer?
Not clearly. In NASA's reanalysis for the area around Janesville, the difference between 1995-2004 and 2015-2024 is 0.9°F, within the normal swing from year to year.

Nearby

MiltonEdgertonBeloitSouth BeloitEvansvilleRocktonWhitewaterRoscoe

More US weather

Which forecast is most accurate in United States?US rain radarNWS vs American vs European: models comparedHow we measure forecast accuracyHow accurate is a 7-day forecast?Wisconsin weather todayAll US citiesHoliday weather abroadEmbed Janesville on your siteThe national forecast models, explained: NBM, UKMO, GEM and ACCESS