Ames weather in December

In December, Ames sees average daytime highs of 33°F and overnight lows near 18°F, with 1.6 in of precipitation across 6 wet days and about 9 hours of daylight. It is the 10th-warmest and 10th-wettest month of the year here.

Highs ease over the month, from about 38°F in the first days to 30°F by the end. The sky is clear or mostly clear about 27% of the time in December, and the air most often feels dry.

Daylight stretches from about 9 h 12 min at the start of December to 9 hours by month's end. Set against the rest of the year, December is Ames's 11th-clearest and 8th-windiest month. For the whole year in context, see Ames's year-round climate.

Daytime high
33°
10th warmest
Overnight low
18°
3rd coldest
Precipitation
1.6 in
6 wet days
Daylight
9 hours
7:42 AM – 4:39 PM
Cloud cover
65%
11th clearest
Wind
10 mph
8th windiest
Solar energy
1.77 kWh/m²
Travel score
0.0
out of 10

Ames is city in Story County, Iowa, United States.

Density
1,035/km²
people per km²
Founded
1864

Air quality: WHO Ambient Air Quality Database. Density & description: Wikidata (CC0), GeoNames.

Temperature in December

Average highAverage lowShaded bands: 10–90% of days

Highs ease over the month, from about 38°F in the first days to 30°F by the end.

A typical December day in Ames reaches about 33°F in the afternoon and slips back to 18°F overnight — a 15°F spread between the day's warmth and the night's chill. On most days the high lands between 17°F and 48°F. Set against its neighbours, December runs about 13°F cooler than November and about 5°F warmer than January.

20°40°60°151015202531
Avg high (°F)Avg low (°F)
13923
23823
33822
43722
53721
63721
73621
83620
93520
103520
113519
123419
133419
143319
153318
163318
173318
183218
193217
203217
213217
223117
233117
243116
253116
263116
273116
283015
293015
303015
313015

How December really feels in Ames

Once humidity and wind are folded in, December averages 0 days that feel above 90°F and 31 that feel at or below 32°F — the comfort signal a plain temperature reading hides.

Days feeling ≥ 90°F
0
heat index over the day's high
Days feeling ≤ 32°F
31
31 feel bitter (≤ 14°F)

The story in December is cold — wind chill drags the overnight "feels like" below the raw low.

Ames weather by month

How December compares with the rest of the year at a glance. December is the 10th-warmest and 10th-wettest month here — the current month is highlighted below.

MonthHigh / Low (°F)Rainfall (inches)Wet daysSnow daysDaylight (hours)Travel score
Jan28° / 13°1.264.89.30.0
Feb33° / 16°1.46.54.710.30.0
Mar47° / 28°2.58.9311.71.5
Apr60° / 40°4.511.1113.14.6
May71° / 52°5.513.60.114.36.0
Jun80° / 62°5.111.80156.3
Jul83° / 65°3.89.6014.76.1
Aug81° / 62°4.09.2013.76.8
Sep74° / 54°3.68.5012.37.2
Oct62° / 42°2.980.510.95.5
Nov47° / 29°2.06.51.79.61.6
Dec33° / 18°1.664.590.0

Cloud cover in December

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 27% of the time in December.

Beyond those clear spells, partly cloudy skies cover about 11% of December, with mostly cloudy or overcast conditions the remaining 61%.

0%25%50%75%100%151015202531
Clearer (%)Cloudier (%)
14060
24060
34159
44159
54159
64159
73961
83961
94060
104060
113961
123961
133961
143862
153862
163763
173763
183862
193763
203763
213763
223862
233763
243763
253763
263862
273862
283862
293862
303961
313961

Chance of precipitation in December

Any precipitationSnow

Ames gets around 1.6 in of rain and snow over 6 wet days in December. The line is the day-by-day chance of measurable precipitation.

Day to day, the chance of measurable precipitation averages around 19% and peaks near 21% on the wettest days, and about 5 days bring snow.

0%10%20%30%151015202531
Rain chance (%)Snow chance (%)
12111
22012
32012
42013
52013
62013
72014
81914
91914
101914
111914
121914
131914
141914
151914
161914
171914
181914
191914
201914
211914
221914
231914
241914
251914
261914
271914
281914
291914
301914
311914

Humidity in December

DryComfortableHumidMuggyOppressiveMiserable

Most of December feels dry — the stacked bands show each day's mix of comfort levels, read off the dew point.

By dew point, December lands in the dry band about 100% of days. It rarely turns muggy — the humid and sticky bands barely register.

0%25%50%75%100%151015202531
Dry (%)
1100
2100
3100
4100
5100
6100
7100
8100
9100
10100
11100
12100
13100
14100
15100
16100
17100
18100
19100
20100
21100
22100
23100
24100
25100
26100
27100
28100
29100
30100
31100

Wind in December

Winds average 10 mph in December.

Across December, daily wind ranges from about 9 mph on the calmest days to 10 mph at its breeziest. It stays fairly steady from day to day.

051015151015202531
Wind speed (mph)Feels
110light breeze
210light breeze
310light breeze
410light breeze
59light breeze
69light breeze
79light breeze
89light breeze
99light breeze
109light breeze
119light breeze
129light breeze
139light breeze
149light breeze
159light breeze
1610light breeze
1710light breeze
1810light breeze
1910light breeze
2010light breeze
2110light breeze
2210light breeze
2310light breeze
2410light breeze
2510light breeze
2610light breeze
2710light breeze
2810light breeze
2910light breeze
3010light breeze
3110light breeze

Sunrise & sunset in December

DaylightNight

Daylight runs from about 9 h 12 min at the start of December to 9 hours by month's end. The lit band spans sunrise to sunset each day.

Days shrink by about 12 minutes over December. Sunrise moves from 7:29 AM to 7:48 AM, and sunset from 4:39 PM to 4:47 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202531
Daylight (h)Sunrise (AM)Sunset (PM)
19.27:294:39
29.17:304:39
39.17:314:39
49.17:324:38
59.17:334:38
69.17:344:38
79.17:354:38
89.07:364:38
99.07:374:38
109.07:384:38
119.07:384:38
129.07:394:38
139.07:404:39
149.07:414:39
159.07:414:39
169.07:424:39
178.97:434:39
188.97:434:40
198.97:444:40
208.97:444:41
218.97:454:41
228.97:454:41
238.97:464:42
248.97:464:42
258.97:474:43
268.97:474:44
278.97:474:44
289.07:484:45
299.07:484:45
309.07:484:46
319.07:484:47

Solar energy in December

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in December, about 1.77 kWh/m² — the year's lowest.

For context, solar energy here swings from a low near 1.77 kWh/m² to a high of 6.46 kWh/m² in July across the year — December's 1.77 kWh/m² sits near the bottom.

00.511.522.5151015202531
Solar energy (kWh/m²)Level
11.9Dim
21.8Dim
31.8Dim
41.8Dim
51.8Dim
61.8Dim
71.8Dim
81.8Dim
91.8Dim
101.8Dim
111.8Dim
121.8Dim
131.8Dim
141.8Dim
151.8Dim
161.8Dim
171.8Dim
181.8Dim
191.8Dim
201.8Dim
211.8Dim
221.8Dim
231.8Dim
241.8Dim
251.8Dim
261.8Dim
271.8Dim
281.8Dim
291.8Dim
301.8Dim
311.8Dim
Planning a trip in December

Is December a good time to visit Ames?

Our two travel scores rate December for general sightseeing and for beach or pool weather — 0 (poor) to 10 (ideal).

0.0
Sightseeing
10th-best month of the year
0.0
Beach & pool
10th-best month of the year

December is a weaker month for outdoor sightseeing in Ames.

What to pack for Ames in December

From December's temperature range, rain chance, sun and wind — what's worth putting in the bag.

In December, Ames sees daytime highs around 33°F and nights near 18°F. Pack a warm layer and a heavy coat. About 6 days see rain.

a warm layera heavy coat

UV index in Ames in December

LowModerateHighVery highExtreme

Clear-sky midday UV in December peaks around 2. The full-year curve, shaded by WHO exposure level, is below.

Under clear skies, the midday UV index in Ames peaks around June 19 at about 9 (very high) — sunscreen, a hat and midday shade are essential. It bottoms out near December 21 at about 2 (low).

The index reaches 3 or more — the level where the WHO recommends sun protection — in 8 months of the year.

025710JanFebMarAprMayJunJulAugSepOctNovDecModerateHighVery highHighModerateLowJun 19UV 9Dec 21UV 2
UV index (midday)Level
Jan2Low
Feb3Moderate
Mar4Moderate
Apr6High
May7High
Jun9Very high
Jul8Very high
Aug7Very high
Sep6High
Oct4Moderate
Nov3Moderate
Dec2Low

Air quality in Ames in December

GoodModeratePoorUnhealthyVery unhealthy

Average fine-particle pollution (PM2.5) through the year — so you can see where December falls, not just the annual average.

Air quality in Ames is worst in July — around 16 µg/m³ PM2.5 (moderate), about 2.2× the cleanest month (October, 7 µg/m³).

Modeled monthly averages (CAMS reanalysis, 2015–2024).

01020JanFebMarAprMayJunJulAugSepOctNovDecModerateGoodModerateGoodJul 2016 µg/m³Oct 217 µg/m³
PM2.5 (µg/m³)Level
Jan13Moderate
Feb15Moderate
Mar14Moderate
Apr11Good
May11Good
Jun12Moderate
Jul16Moderate
Aug14Moderate
Sep12Good
Oct7Good
Nov9Good
Dec10Good
Location & terrain

Where is Ames?

Ames sits at 42.0°N, 93.6°W, 942 ft above sea level, in United States. The nearest listed city is Ankeny, 21 mi away.

Topography around Ames

How much the land rises and falls, and what covers it, within 2, 10 and 50 miles of Ames.

Within 2 miles, the terrain around Ames has only modest variations in elevation — a maximum elevation change of 207 ft around an average of 932 ft above sea level; within 10 miles, only modest variations in elevation — a maximum elevation change of 325 ft; within 50 miles, only modest variations in elevation — a maximum elevation change of 568 ft.

The land around Ames is covered by trees (38%) and artificial surfaces (34%) within 2 miles, cropland (74%) within 10 miles, and cropland (78%) within 50 miles.

2 miles
207 ft
10 miles
325 ft
50 miles
568 ft
treesgrasslandcroplandartificial surfaceswater
December weather nearby: Ankeny 21 mi · Johnston 25 mi · Altoona 28 mi · Urbandale 29 mi · Des Moines 30 mi · Clive 30 mi · West Des Moines 32 mi · Waukee 32 mi

United States travel facts

Power plugs
Type A / B
120 V · 60 Hz
Prices
≈ 100% of US
price level, 2025
GDP per capita
$90,027
2025
Happiness
6.8 / 10
World Happiness, 2025
Safe drinking water
98%
of population, 2024
Homicide rate
5.8
per 100k, 2023
Road deaths
12.7
per 100k/yr, 2019
Income group
High
World Bank
Religion
Protestant 47%unaffiliated 23%Roman Catholic 21%Jewish 2%

Sources: World Bank, US State Department, World Happiness Report, WHO/UNICEF, EF EPI, CIA World Factbook.

Data sources

Temperature, precipitation, cloud, humidity, wind and solar figures are a 1991–2020 climatology for Ames (42.0347°, -93.6199°, elevation 942 ft), computed from hourly ERA5 reanalysis — contains modified Copernicus Climate Change Service information. Sun figures are astronomical calculations, not observations. City data © GeoNames, CC BY 4.0. Map outlines from Natural Earth (public domain); interactive map © Google. UV index is derived from CAMS (Copernicus Atmosphere Monitoring Service) clear-sky UV data — contains modified Copernicus Atmosphere Monitoring Service information. Monthly air-quality (PM2.5) seasonality is from the CAMS EAC4 reanalysis (Copernicus Atmosphere Monitoring Service), scaled to the WHO annual mean where available. Topography is sampled from the Copernicus DEM GLO-90 elevation model (© ESA/Airbus) and ESA WorldCover 2021 land cover (CC BY 4.0).