Sioux City weather in December: Sioux City, Iowa: normal highs, lows, rain and records for December
Sioux City in December has a normal high of 33°F and a normal low of 15°F, a daily mean of 24°F, falling from 39°F on the 1st to 30°F by the 31st. Measurable precipitation falls on 7 days in a normal December, 0.99 inches in all. (NOAA 1991-2020 normals)
In metric: a normal high of 1°C and low of −10°C, 25 mm of precipitation and 19 cm of snow in December.
- NOAA stationSioux City Airport
- Station IDUSW00014943
- Location42.39°N 96.38°W
- Elevation1,095 ft (334 m)
- From the center7 miles
- Population86,875
- Jan 30° 10°
- Feb 34° 15°
- Mar 48° 26°
- Apr 61° 37°
- May 72° 49°
- Jun 82° 59°
- Jul 85° 63°
- Aug 83° 61°
- Sep 77° 51°
- Oct 63° 38°
- Nov 47° 25°
- Dec 33° 15°
Each month: normal high (large) and low, °F. Fill: the month's normal mean, colder blue to hotter red.
How warm is Sioux City in December?
The normal high is 33°F and the normal low 15°F, for a daily mean of 24.1°F. December is 11.8°F cooler than November and 4.1°F warmer than January. December is the 11th warmest month of the year in Sioux City and the 10th wettest. Across the month the normal high falls 9°F, from 39°F on December 1 to 30°F on December 31. From one year to the next December's mean temperature typically moves about 4.9°F either way (NOAA's standard deviation), so roughly two Decembers in three average between 19°F and 29°F.
Bars above: each day's normal high to low. Columns below: the chance of 0.01 inch or more of precipitation that day, on a scale of 0 to 100% (highest 22%).
| Day | High | Low | Chance of 0.01 in | Chance of 0.10 in |
|---|---|---|---|---|
| December 1 | 39°F | 19°F | 21% | 8% |
| December 8 | 36°F | 17°F | 21% | 8% |
| December 15 | 33°F | 15°F | 22% | 8% |
| December 22 | 31°F | 13°F | 22% | 8% |
| December 31 | 30°F | 12°F | 22% | 8% |
Every day of December: normal high, low and chance of precipitation (warmest afternoon December 1, coldest night December 31)
| Day | High | Low | Chance of 0.01 in | Chance of 0.10 in | Daylight |
|---|---|---|---|---|---|
| December 1 | 39°F | 19°F | 21% | 8% | 9 h 20 min |
| December 2 | 39°F | 19°F | 21% | 8% | 9 h 20 min |
| December 3 | 38°F | 18°F | 21% | 8% | 9 h 20 min |
| December 4 | 38°F | 18°F | 21% | 8% | 9 h 20 min |
| December 5 | 37°F | 18°F | 21% | 8% | 9 h 10 min |
| December 6 | 37°F | 17°F | 21% | 8% | 9 h 10 min |
| December 7 | 36°F | 17°F | 21% | 8% | 9 h 10 min |
| December 8 | 36°F | 17°F | 21% | 8% | 9 h 10 min |
| December 9 | 36°F | 17°F | 21% | 8% | 9 h 10 min |
| December 10 | 35°F | 16°F | 21% | 8% | 9 h 10 min |
| December 11 | 35°F | 16°F | 21% | 8% | 9 h 10 min |
| December 12 | 34°F | 16°F | 22% | 8% | 9 h 10 min |
| December 13 | 34°F | 15°F | 22% | 8% | 9 h 10 min |
| December 14 | 34°F | 15°F | 22% | 8% | 9 h 10 min |
| December 15 | 33°F | 15°F | 22% | 8% | 9 h 10 min |
| December 16 | 33°F | 15°F | 22% | 8% | 9 h 10 min |
| December 17 | 33°F | 14°F | 22% | 8% | 9 h 10 min |
| December 18 | 32°F | 14°F | 22% | 8% | 9 h |
| December 19 | 32°F | 14°F | 22% | 8% | 9 h |
| December 20 | 32°F | 14°F | 22% | 8% | 9 h |
| December 21 | 31°F | 13°F | 22% | 8% | 9 h |
| December 22 | 31°F | 13°F | 22% | 8% | 9 h |
| December 23 | 31°F | 13°F | 22% | 8% | 9 h |
| December 24 | 31°F | 13°F | 22% | 8% | 9 h |
| December 25 | 31°F | 13°F | 22% | 8% | 9 h |
| December 26 | 30°F | 12°F | 22% | 8% | 9 h |
| December 27 | 30°F | 12°F | 22% | 8% | 9 h 10 min |
| December 28 | 30°F | 12°F | 22% | 8% | 9 h 10 min |
| December 29 | 30°F | 12°F | 22% | 8% | 9 h 10 min |
| December 30 | 30°F | 12°F | 22% | 8% | 9 h 10 min |
| December 31 | 30°F | 12°F | 22% | 8% | 9 h 10 min |
- Normal high
- 33°FDecember average
- Normal low
- 15°FDecember average
- Precipitation
- 0.99 inmonth total
- Days with precipitation
- 70.01 inch or more
- Snowfall
- 7.6 inmonth total
- Nights at 32°F or colder
- 30
- Daylight
- 9 h 20 min to 9 h 10 minDecember 1 to December 31
- Sunshine
- 69%of clear-sky sunlight (NASA)
Source: NOAA NCEI 1991-2020 daily normals, station USW00014943; monthly normals. Daylight is computed from the place's latitude with NOAA's solar equations.
Does it rain or snow in Sioux City in December?
On a given December day the chance of 0.01 inch or more is 22% on average, highest around December 28 (22%). In all, 0.99 in falls on 7 days of a normal December.
In a normal December in Sioux City, 30 nights fall to freezing, 13 days stay below freezing all day and snowfall averages 7.6 inches.
Snow falls on 5 days in a normal December, and an inch or more covers the ground on 13 days.
Source: NOAA NCEI 1991-2020 daily and monthly normals, station USW00014943.
How humid and windy is Sioux City in December?
At 3 p.m. the normal temperature is 27°F with 66% relative humidity and a dew point of 17°F; at 6 a.m. it is 17°F with 81% humidity. The wind averages 10.7 mph, most often from the northwest in the afternoon. A dew point under 50°F feels dry.
| Time | Temperature | Dew point | Humidity | Wind | Clear or few clouds |
|---|---|---|---|---|---|
| 6 a.m. | 17°F | 12°F | 81% | 10.1 mph | 50% |
| 9 a.m. | 18°F | 13°F | 81% | 10.2 mph | 55% |
| noon | 24°F | 16°F | 71% | 12.1 mph | 51% |
| 3 p.m. | 27°F | 17°F | 66% | 12.6 mph | 60% |
| 6 p.m. | 24°F | 16°F | 74% | 10.4 mph | 55% |
| 9 p.m. | 21°F | 15°F | 79% | 10.1 mph | 62% |
Source: NOAA NCEI 1991-2020 hourly normals, station USW00014943. Hourly normals exist only for NOAA's first-order stations; a dash where NOAA publishes no value for that hour (the sky at some hours).
What are the records for December in Sioux City?
The warmest December temperature on Sioux City's official record (since 1889) is 71°F, on December 6, 1939; the coldest is −28°F, on December 29, 1917. The wettest December brought 2.87 in (1911); the snowiest, 34.0 inches (2009).
The December mean against the 1991-2020 normal of 24.1°F: 2021 31.6°F (+7.5), 2022 20.6°F (−3.5), 2023 32.9°F (+8.8), 2024 29.0°F (+4.9), 2025 26.4°F (+2.3). 4 of 5 ran warmer than normal.
| December | Mean | Against normal | Precip. |
|---|---|---|---|
| 2021 | 31.6°F | +7.5°F | 0.65 in |
| 2022 | 20.6°F | −3.5°F | 1.83 in |
| 2023 | 32.9°F | +8.8°F | 1.59 in |
| 2024 | 29.0°F | +4.9°F | 0.49 in |
| 2025 | 26.4°F | +2.3°F | 0.61 in |
Source: records: ACIS, NWS threaded record SUXthr; recent months: ACIS, station USW00014943. Records and recent months use complete months only.
How does December in Sioux City compare across Iowa?
Across the 132 places PlainClimate covers in Iowa, December normal highs run from 27°F in Northwood to 38°F in Keokuk; Sioux City's is 33°F.
Source: NOAA NCEI 1991-2020 monthly normals for every station in the state.