Gwynn Oak weather in December

In December, Gwynn Oak sees average daytime highs of 46°F and overnight lows near 32°F, with 3.7 in of precipitation across 9 wet days and about 9.3 hours of daylight. It is the 10th-warmest and 7th-wettest month of the year here.

Highs ease over the month, from about 49°F in the first days to 44°F by the end. The sky is clear or mostly clear about 33% of the time in December, and the air most often feels dry.

Daylight stretches from about 9 h 24 min at the start of December to 9 h 18 min by month's end. Set against the rest of the year, December is Gwynn Oak's 6th-clearest and 5th-windiest month. For the whole year in context, see Gwynn Oak's year-round climate.

Daytime high
46°
10th warmest
Overnight low
32°
3rd coldest
Precipitation
3.7 in
9 wet days
Daylight
9 h 12 min
7:26 AM – 4:40 PM
Cloud cover
59%
6th clearest
Wind
8 mph
5th windiest
Solar energy
1.92 kWh/m²
Travel score
1.2
out of 10

Gwynn Oak is human settlement in United States of America.

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 49°F in the first days to 44°F by the end.

A typical December day in Gwynn Oak reaches about 46°F in the afternoon and slips back to 32°F overnight — a 13°F spread between the day's warmth and the night's chill. On most days the high lands between 34°F and 58°F. Set against its neighbours, December runs about 9°F cooler than November and about 4°F warmer than January.

20°40°60°151015202531
Avg high (°F)Avg low (°F)
15036
24935
34935
44935
54835
64834
74734
84734
94733
104633
114633
124633
134633
144632
154532
164532
174532
184532
194532
204531
214431
224431
234431
244431
254431
264431
274431
284431
294430
304430
314330

How December really feels in Gwynn Oak

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
wind chill below the day's low

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

Gwynn Oak weather by month

How December compares with the rest of the year at a glance. December is the 10th-warmest and 7th-wettest month here — the current month is highlighted below.

MonthHigh / Low (°F)Rainfall (inches)Wet daysSnow daysDaylight (hours)Travel score
Jan42° / 28°3.18.539.50.2
Feb44° / 29°2.98.53.210.50.9
Mar53° / 36°4.010.32.211.73.0
Apr64° / 47°3.510.30.2135.7
May73° / 56°3.811.4014.16.5
Jun82° / 65°3.711.6014.75.8
Jul86° / 70°4.212.1014.54.7
Aug84° / 69°3.710.9013.55.4
Sep78° / 61°4.69.1012.36.9
Oct66° / 50°3.680116.4
Nov55° / 39°3.07.60.29.83.8
Dec46° / 32°3.791.79.31.2

Cloud cover in December

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 33% of the time in December.

Beyond those clear spells, partly cloudy skies cover about 15% of December, with mostly cloudy or overcast conditions the remaining 52%.

0%25%50%75%100%151015202531
Clearer (%)Cloudier (%)
14951
24951
34951
44852
54753
64654
74654
84654
94654
104555
114555
124555
134654
144654
154654
164654
174753
184852
194753
204753
214951
224951
234852
244951
254951
264951
275050
284951
295050
305050
315050

Chance of precipitation in December

Any precipitationSnow

Gwynn Oak gets around 3.7 in of rain and snow over 9 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 29% and peaks near 31% on the wettest days, and about 2 days bring snow.

0%10%20%30%40%151015202531
Rain chance (%)Snow chance (%)
1293
2303
3304
4304
5304
6304
7315
8315
9315
10316
11316
12306
13306
14306
15306
16306
17306
18296
19296
20296
21286
22286
23276
24276
25275
26275
27275
28276
29276
30276
31286

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 99% of days. It rarely turns muggy — the humid and sticky bands barely register.

0%25%50%75%100%151015202531
Dry (%)Comfortable (%)
1973
2973
3973
4982
5982
6982
7982
8982
9991
10991
11991
12991
13991
14991
15991
16991
17991
18991
19991
20991
21991
22991
23991
24991
25991
26991
27991
28991
29991
30991
31991

Wind in December

Winds average 8 mph in December.

Across December, daily wind ranges from about 7 mph on the calmest days to 8 mph at its breeziest. It stays fairly steady from day to day.

0246810151015202531
Wind speed (mph)Feels
17light breeze
27light breeze
37light breeze
47light breeze
57light breeze
67light breeze
77light breeze
87light breeze
97light breeze
107light breeze
117light breeze
127light breeze
137light breeze
147light breeze
158light breeze
168light breeze
178light breeze
188light breeze
198light breeze
208light breeze
218light breeze
228light breeze
238light breeze
248light breeze
258light breeze
268light breeze
278light breeze
288light breeze
298light breeze
308light breeze
318light breeze

Sunrise & sunset in December

DaylightNight

Daylight runs from about 9 h 24 min at the start of December to 9 h 18 min by month's end. The lit band spans sunrise to sunset each day.

Days shrink by about 6 minutes over December. Sunrise moves from 7:14 AM to 7:32 AM, and sunset from 4:39 PM to 4:48 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202531
Daylight (h)Sunrise (AM)Sunset (PM)
19.47:144:39
29.47:154:39
39.47:154:39
49.47:164:39
59.47:174:39
69.37:184:39
79.37:194:39
89.37:204:39
99.37:214:39
109.37:214:39
119.37:224:39
129.37:234:39
139.37:244:39
149.37:244:40
159.27:254:40
169.27:264:40
179.27:264:41
189.27:274:41
199.27:274:41
209.27:284:42
219.27:284:42
229.27:294:42
239.27:294:43
249.27:304:43
259.27:304:44
269.27:314:45
279.27:314:45
289.27:314:46
299.27:324:46
309.37:324:47
319.37:324:48

Solar energy in December

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in December, about 1.92 kWh/m² — the year's lowest.

For context, solar energy here swings from a low near 1.92 kWh/m² to a high of 6.11 kWh/m² in June across the year — December's 1.92 kWh/m² sits near the bottom.

0123151015202531
Solar energy (kWh/m²)Level
12.0Moderate
22.0Moderate
32.0Moderate
42.0Dim
52.0Dim
61.9Dim
71.9Dim
81.9Dim
91.9Dim
101.9Dim
111.9Dim
121.9Dim
131.9Dim
141.9Dim
151.9Dim
161.9Dim
171.9Dim
181.9Dim
191.9Dim
201.9Dim
211.9Dim
221.9Dim
231.9Dim
241.9Dim
251.9Dim
261.9Dim
271.9Dim
281.9Dim
291.9Dim
302.0Dim
312.0Dim
Planning a trip in December

Hazard calendar for Gwynn Oak

In seasonPeak

None of Gwynn Oak's seasonal hazards are active in December. The full-year calendar below shows when the rainy season, cyclone risk and dust haze do peak.

Gwynn Oak sits in the Atlantic hurricane belt; the season peaks August–October.

Atlantic hurricane
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec

Is December a good time to visit Gwynn Oak?

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

1.2
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 Gwynn Oak.

What to pack for Gwynn Oak in December

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

In December, Gwynn Oak sees daytime highs around 46°F and nights near 32°F. Pack a warm layer. Worth having: a heavy coat and rain gear. About 9 days see rain.

a warm layera heavy coatrain gear

Sea temperature near Gwynn Oak in December

The nearest coast averages about 44°F in December — the other half of the beach question. The full-year curve and swim-comfort zones are below.

The sea at the nearest coast (about 22 mi away) is warmest in August at about 78°F and coldest in February near 36°F.

It's comfortable for a long swim from Jun 16 to Oct 5 — about 3.7 months when the water holds above 68°F.

30°40°50°60°70°80°JanFebMarAprMayJunJulAugSepOctNovDecbracingcoolrefreshingwarmtropicalcomfortable to swim
Sea temperature (°F)Comfort
Jan38Bracing
Feb36Bracing
Mar40Bracing
Apr47Bracing
May58Bracing
Jun68Refreshing
Jul76Warm
Aug78Warm
Sep74Refreshing
Oct65Cool
Nov53Bracing
Dec44Bracing

UV index in Gwynn Oak 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 Gwynn Oak peaks around July 10 at about 9 (very high) — sunscreen, a hat and midday shade are essential. It bottoms out near December 19 at about 2 (low).

The index reaches 3 or more — the level where the WHO recommends sun protection — in 9 months of the year.

025710JanFebMarAprMayJunJulAugSepOctNovDecModerateHighVery highHighModerateLowJul 10UV 9Dec 19UV 2
UV index (midday)Level
Jan2Low
Feb3Moderate
Mar5Moderate
Apr6High
May8Very high
Jun9Very high
Jul9Very high
Aug7High
Sep6High
Oct4Moderate
Nov3Moderate
Dec2Low

Air quality in Gwynn Oak 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 Gwynn Oak is worst in July — around 17 µg/m³ PM2.5 (moderate), about 2.0× the cleanest month (November, 8 µg/m³).

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

01020JanFebMarAprMayJunJulAugSepOctNovDecGoodModerateGoodJul 1216 µg/m³Nov 118 µg/m³
PM2.5 (µg/m³)Level
Jan10Good
Feb12Good
Mar13Moderate
Apr13Moderate
May15Moderate
Jun16Moderate
Jul17Moderate
Aug14Moderate
Sep12Good
Oct9Good
Nov8Good
Dec10Good
Location & terrain

Where is Gwynn Oak?

Gwynn Oak sits at 39.3°N, 76.7°W, 427 ft above sea level, in United States. The nearest listed city is Lochearn, 1.9 mi away.

Topography around Gwynn Oak

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

Within 2 miles, the terrain around Gwynn Oak has only modest variations in elevation — a maximum elevation change of 348 ft around an average of 397 ft above sea level; within 10 miles, significant variations in elevation — a maximum elevation change of 925 ft; within 50 miles, large variations in elevation — a maximum elevation change of 2,031 ft.

The land around Gwynn Oak is covered by trees (50%) and artificial surfaces (39%) within 2 miles, trees (58%) and artificial surfaces (27%) within 10 miles, and trees (52%) within 50 miles.

2 miles
348 ft
10 miles
925 ft
50 miles
2,031 ft
treesgrasslandcroplandartificial surfaceswater
December weather nearby: Lochearn 1.9 mi · Woodlawn 1.9 mi · Pikesville 3.1 mi · Milford Mill 4.3 mi · Catonsville 5.0 mi · Baltimore 5.0 mi · Arbutus 5.6 mi · Randallstown 6.2 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 Gwynn Oak (39.3326°, -76.6928°, elevation 427 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. Tropical-cyclone seasons are the published climatological basin seasons (NOAA National Hurricane Center / regional warning centres). Sea temperatures are the NOAA OISST v2.1 1991–2020 monthly climatology (public domain), sampled at the nearest ocean point. 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).