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CheckWeather USSioux City
Forecast confidence: High · models disagree by 3°F

Sioux City weather

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Showers,rain likely tomorrow

NWS, the American and the European model agree on a high near 86° in Sioux City today. Tomorrow looks light rain around 72°, with a 50% chance of rain.

86°65°
72°63°
64°60°
61°55°
63°52°
67°50°
Todaymodels agreeTomorrowmodels agreeSundaymodels agreeMondaysplit ±4°Tuesdaysplit ±5°Wednesdaysplit ±8°
NWSNational Blend (NBM)
85°
Showers
Today 85°·Low 66°·Rain 47%
AmericanNOAA GFS
88°
Light drizzle
Today 88°·Low 65°·Rain 47%
EuropeanECMWF
87°
Rain
Today 87°·Low 65°·Rain 86%
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Sioux City weather alerts and warnings

active National Weather Service watches, warnings and advisories

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Sioux City weather in numbers

from 30 years of measured normals

Sioux City swings 72°F across the year, from 84°F highs in July to 12°F lows in January, and June is usually the wettest month in a year that brings about 31 in of precipitation.

Warmest month
July
84°F average high
Coldest month
January
12°F average low
Wettest month
June
31 in a year
Below freezing
4 months
January, February, March and December
Comfortable
3 months
April, May and October
Residents
83,000
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The weather map: all three models at once

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

where the models agree, and where they split
Today
Showers
86° 65°
models agree
Tomorrow
Light rain
72° 63°
models agree
Sun
Light drizzle
64° 60°
models agree
Mon
Drizzle
61° 55°
±4°
Tue
Cloudy
63° 52°
±5°
Wed
Cloudy
67° 50°
±8°
Thu
Light drizzle
67° 54°
models agree
Fri
Partly cloudy
65° 57°
±11°
Sat
Cloudy
69° 57°
±8°
Sun
Heavy drizzle
68° 57°
±9°
Mon
Light drizzle
65° 53°
±7°
Tue
Cloudy
64° 46°
models agree
Wed
Cloudy
67° 46°
±10°
Thu
Cloudy
77° 52°
models agree

Sioux City, Iowa (IA) is at its warmest in Jul (average highs near 84°F) and coldest in Jan (lows around 12°F), with roughly 31 in of precipitation across the year. Below, compare what NWS, American, European forecast for Sioux City 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.

Sioux City climate by month

average daytime high and overnight low across a typical year
Jan
25°
12°
Feb
42°
21°
Mar
47°
27°
Apr
61°
41°
May
75°
53°
Jun
83°
63°
Jul
84°
65°
Aug
84°
66°
Sep
81°
61°
Oct
66°
47°
Nov
50°
33°
Dec
38°
24°

Which forecast is most accurate in Sioux City?

CheckWeather Score, graded against the weather that actually happened
ProviderCheckWeather-scoreTempWindRainRun by
European logo
European ★ Best
91
/100rank #1
96±0.4°F95±1.5 mph8290% hitECMWF - European Centre for Medium-Range Weather ForecastsReading, United Kingdom
American logo
American
75
/100rank #2
87±1.3°F94±2.0 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±3°85° to 88°±39%47% to 86% chance
Tomorrow±3°70° to 73°±30%20% to 50% chance
Sun±4°63° to 66°±2%39% to 41% chance
Mon±4°60° to 64°±3%60% to 63% chance
Tue±5°60° to 65°±1%5% to 6% 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 Sioux City

today, local time
Sunrise
07:08
Sunset
19:29
Daylight
12h 21m

Common questions

What's the weather in Sioux City today?
On this page we show what NWS, American, European each forecast for Sioux City 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 Sioux City today or tomorrow?
Check the hourly strip and 7-day forecast above. We compare rain from NWS, American, European for Sioux City 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 Sioux City?
Over the last 30 days, the European model has been the most accurate for Sioux City (CheckWeather Score 91/100), 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 Sioux City?
July is typically the warmest month in Sioux City, with average highs around 84°F.
How cold does Sioux City get?
The coldest month in Sioux City is January, when overnight lows average about 12°F.
How much rain does Sioux City get?
Sioux City sees roughly 31 in of precipitation a year, with June usually the wettest month.

Nearby

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