St. Marys weather in December

In December, St. Marys sees average daytime highs of 64°F and overnight lows near 51°F, with 2.5 in of rain across 7.4 wet days and about 10 hours of daylight. It is the 11th-warmest and 8th-wettest month of the year here.

Highs ease over the month, from about 67°F in the first days to 63°F by the end. The sky is clear or mostly clear about 35% of the time in December, and the air most often feels dry.

Daylight stretches from about 10 h 12 min at the start of December to 10 hours by month's end. Set against the rest of the year, December is St. Marys's 8th-clearest and 6th-windiest month. For the whole year in context, see St. Marys's year-round climate.

Daytime high
64°
11th warmest
Overnight low
51°
3rd coldest
Rainfall
2.5 in
7.4 wet days
Daylight
10 hours
7:22 AM – 5:23 PM
Cloud cover
56%
8th clearest
Wind
9 mph
6th windiest
Solar energy
2.74 kWh/m²
Travel score
6.3
out of 10

St. Marys is city in Camden County, Georgia, USA.

Density
279/km²
people per km²
Founded
1792

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 67°F in the first days to 63°F by the end.

A typical December day in St. Marys reaches about 64°F in the afternoon and slips back to 51°F overnight — a 14°F spread between the day's warmth and the night's chill. On most days the high lands between 54°F and 74°F. Set against its neighbours, December runs about 6°F cooler than November and about 2°F warmer than January.

30°40°50°60°70°80°151015202531
Avg high (°F)Avg low (°F)
16753
26753
36753
46653
56653
66652
76652
86652
96552
106552
116551
126551
136551
146551
156451
166451
176451
186450
196450
206450
216450
226450
236350
246350
256350
266349
276349
286349
296349
306349
316349

How December really feels in St. Marys

Once humidity and wind are folded in, December averages 0 days that feel above 90°F and 0 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
0
wind chill below the day's low

December sits comfortably in between — no days that feel dangerously hot or drop to a hard freeze once humidity and wind are folded in.

St. Marys weather by month

How December compares with the rest of the year at a glance. December is the 11th-warmest and 8th-wettest month here — the current month is highlighted below.

MonthHigh / Low (°F)Rainfall (inches)Wet daysDaylight (hours)Travel score
Jan62° / 48°2.97.710.25.7
Feb65° / 50°2.57.210.96.2
Mar70° / 55°2.87.311.87.0
Apr75° / 61°2.36.912.77.5
May82° / 68°2.58.513.56.6
Jun86° / 74°5.117.5144.3
Jul88° / 76°4.618.213.83.7
Aug87° / 76°5.820.413.13.7
Sep83° / 74°5.415.512.25.0
Oct78° / 66°3.28.911.27.1
Nov70° / 57°1.86.110.47.2
Dec64° / 51°2.57.4106.3

Cloud cover in December

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 35% of the time in December.

Beyond those clear spells, partly cloudy skies cover about 13% of December, with mostly cloudy or overcast conditions the remaining 51%. Skies tend to cloud over as the month goes on.

0%25%50%75%100%151015202531
Clearer (%)Cloudier (%)
15644
25644
35545
45545
55347
65248
75248
85149
95050
105050
115050
124951
134951
144951
154753
164753
174753
184852
194852
204852
214753
224852
234753
244753
254654
264555
274555
284555
294555
304555
314456

Chance of precipitation in December

Any precipitation

St. Marys gets around 2.5 in of rain over 7.4 wet days in December. The line is the day-by-day chance of measurable precipitation.

Day to day, the chance of measurable rain averages around 24% and peaks near 26% on the wettest days.

0%10%20%30%40%151015202531
Rain chance (%)
120
220
321
421
522
622
723
823
924
1024
1125
1225
1325
1425
1526
1626
1726
1826
1926
2026
2126
2225
2325
2425
2525
2625
2724
2824
2924
3023
3123

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 61% of days. Sticky, muggy-or-worse air turns up on roughly 6% of them.

0%25%50%75%100%151015202531
Dry (%)Comfortable (%)Humid (%)Muggy (%)
15418199
25418199
35518198
45518198
55618188
65618188
75718187
85718187
95818177
105818177
116018166
126018166
136018166
146217156
156217156
166217156
176317146
186417145
196417145
206517135
216517135
226517135
236517135
246517135
256517135
266418135
276418135
286418135
296418135
306518134
316419134

Wind in December

Winds average 9 mph in December.

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

051015151015202531
Wind speed (mph)Feels
19light breeze
29light breeze
39light breeze
49light breeze
59light breeze
69light breeze
79light breeze
89light breeze
99light breeze
109light breeze
119light breeze
129light breeze
139light breeze
149light breeze
159light breeze
169light breeze
179light breeze
189light breeze
199light breeze
209light breeze
219light breeze
229light breeze
239light breeze
249light breeze
259light breeze
269light breeze
279light breeze
289light breeze
299light breeze
309light breeze
319light breeze

Sunrise & sunset in December

DaylightNight

Daylight runs from about 10 h 12 min at the start of December to 10 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 7:11 AM to 7:28 AM, and sunset from 5:21 PM to 5:30 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202531
Daylight (h)Sunrise (AM)Sunset (PM)
110.27:115:21
210.17:125:21
310.17:135:21
410.17:145:21
510.17:145:21
610.17:155:21
710.17:165:21
810.17:175:21
910.17:175:21
1010.17:185:21
1110.07:195:22
1210.07:195:22
1310.07:205:22
1410.07:215:22
1510.07:215:23
1610.07:225:23
1710.07:225:23
1810.07:235:24
1910.07:235:24
2010.07:245:25
2110.07:245:25
2210.07:255:25
2310.07:255:26
2410.07:265:26
2510.07:265:27
2610.07:275:27
2710.07:275:28
2810.07:275:29
2910.07:285:29
3010.07:285:30
3110.07:285:30

Solar energy in December

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in December, about 2.74 kWh/m² — the year's lowest.

For context, solar energy here swings from a low near 2.74 kWh/m² to a high of 6.45 kWh/m² in May across the year — December's 2.74 kWh/m² sits near the bottom.

0123151015202531
Solar energy (kWh/m²)Level
12.9Moderate
22.9Moderate
32.9Moderate
42.9Moderate
52.9Moderate
62.8Moderate
72.8Moderate
82.8Moderate
92.8Moderate
102.8Moderate
112.7Moderate
122.7Moderate
132.7Moderate
142.7Moderate
152.7Moderate
162.7Moderate
172.7Moderate
182.7Moderate
192.7Moderate
202.7Moderate
212.7Moderate
222.7Moderate
232.7Moderate
242.7Moderate
252.7Moderate
262.7Moderate
272.7Moderate
282.7Moderate
292.7Moderate
302.8Moderate
312.8Moderate
Planning a trip in December

Hazard calendar for St. Marys

In seasonPeak

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

St. Marys sits in the Atlantic hurricane belt; the season peaks August–October.

St. Marys's rainy season runs June–October, when most of the year's rain falls.

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

Is December a good time to visit St. Marys?

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

6.3
Sightseeing
6th-best month of the year
2.2
Beach & pool
10th-best month of the year

December is a reasonable time to visit St. Marys for sightseeing.

What to pack for St. Marys in December

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

In December, St. Marys sees daytime highs around 64°F and nights near 51°F. Little to plan around — just the basics. About 7 days see rain.

Sea temperature near St. Marys in December

The nearest coast averages about 64°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 12 mi away) is warmest in August at about 83°F and coldest in February near 60°F.

It's comfortable for a long swim from Apr 15 to Nov 24 — about 7.4 months when the water holds above 68°F.

60°70°80°JanFebMarAprMayJunJulAugSepOctNovDecbracingcoolrefreshingwarmtropicalcomfortable to swim
Sea temperature (°F)Comfort
Jan61Cool
Feb60Cool
Mar63Cool
Apr68Refreshing
May75Refreshing
Jun80Warm
Jul82Warm
Aug83Tropical
Sep82Warm
Oct77Warm
Nov70Refreshing
Dec64Cool

UV index in St. Marys in December

LowModerateHighVery highExtreme

Clear-sky midday UV in December peaks around 3 — enough to warrant sun protection. The full-year curve, shaded by WHO exposure level, is below.

Under clear skies, the midday UV index in St. Marys peaks around June 22 at about 10 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near December 19 at about 3 (moderate).

The index reaches 3 or more — the level where the WHO recommends sun protection — every month of the year.

025710JanFebMarAprMayJunJulAugSepOctNovDecModerateHighVery highExtremeVery highHighModerateJun 22UV 10Dec 19UV 3
UV index (midday)Level
Jan4Moderate
Feb6High
Mar7High
Apr7High
May8Very high
Jun10Extreme
Jul10Very high
Aug9Very high
Sep8Very high
Oct6High
Nov5Moderate
Dec3Moderate

Air quality in St. Marys 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 St. Marys is worst in July — around 18 µg/m³ PM2.5 (moderate), about 2.6× the cleanest month (December, 7 µg/m³).

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

01020JanFebMarAprMayJunJulAugSepOctNovDecGoodModerateGoodJul 1618 µg/m³Dec 127 µg/m³
PM2.5 (µg/m³)Level
Jan9Good
Feb13Moderate
Mar14Moderate
Apr14Moderate
May15Moderate
Jun16Moderate
Jul18Moderate
Aug16Moderate
Sep11Good
Oct8Good
Nov7Good
Dec7Good
Location & terrain

Where is St. Marys?

St. Marys sits at 30.7°N, 81.5°W, 10 ft above sea level, in United States. The nearest listed city is Kingsland, 9.9 mi away.

Topography around St. Marys

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

Within 2 miles, the terrain around St. Marys has only modest variations in elevation — a maximum elevation change of 79 ft around an average of 10 ft above sea level; within 10 miles, only modest variations in elevation — a maximum elevation change of 125 ft; within 50 miles, only modest variations in elevation — a maximum elevation change of 295 ft.

The land around St. Marys is covered by wetland (41%), trees (25%) and water (23%) within 2 miles, trees (43%) and water (26%) within 10 miles, and trees (58%) and water (29%) within 50 miles.

2 miles
79 ft
10 miles
125 ft
50 miles
295 ft
treesgrasslandartificial surfaceswaterwetland
December weather nearby: Kingsland 9.9 mi · Jacksonville 29 mi · Brunswick 29 mi · Jacksonville Beach 32 mi · Ponte Vedra Beach 35 mi · Palm Valley 39 mi · Oakleaf Plantation 42 mi · Fruit Cove 43 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 St. Marys (30.7305°, -81.5465°, elevation 10 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).