Summerville weather in May

In May, Summerville sees average daytime highs of 82°F and overnight lows near 64°F, with 3.2 in of rain across 10.3 wet days and about 13.7 hours of daylight. It is the 5th-warmest and 10th-wettest month of the year here.

Highs climb over the month, from about 80°F in the first days to 85°F by the end. The sky is clear or mostly clear about 36% of the time in May, and the air most often feels muggy.

Daylight stretches from about 13 h 18 min at the start of May to 14 hours by month's end. Set against the rest of the year, May is Summerville's 4th-clearest and 7th-windiest month. For the whole year in context, see Summerville's year-round climate.

Daytime high
82°
5th warmest
Overnight low
64°
8th coldest
Rainfall
3.2 in
10.3 wet days
Daylight
13 h 42 min
5:26 AM – 7:08 PM
Cloud cover
54%
4th clearest
Wind
6 mph
7th windiest
Solar energy
6.29 kWh/m²
Travel score
6.1
out of 10

Summerville is town in South Carolina, United States.

Density
974/km²
people per km²
Founded
1847

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

Temperature in May

Average highAverage lowShaded bands: 10–90% of days

Highs climb over the month, from about 80°F in the first days to 85°F by the end.

A typical May day in Summerville reaches about 82°F in the afternoon and slips back to 64°F overnight — a 19°F spread between the day's warmth and the night's chill. On most days the high lands between 75°F and 90°F. Set against its neighbours, May runs about 7°F warmer than April and about 5°F cooler than June.

40°60°80°151015202531
Avg high (°F)Avg low (°F)
17959
27960
38060
48060
58060
68061
78161
88161
98162
108162
118262
128262
138263
148263
158263
168263
178364
188364
198364
208364
218365
228465
238465
248466
258466
268566
278567
288567
298567
308567
318568

How May really feels in Summerville

Once humidity and wind are folded in, May 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

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

Summerville weather by month

How May compares with the rest of the year at a glance. May is the 5th-warmest and 10th-wettest month here — the current month is highlighted below.

MonthHigh / Low (°F)Rainfall (inches)Wet daysDaylight (hours)Travel score
Jan59° / 39°3.28.810.14.8
Feb62° / 42°3.28.110.85.5
Mar69° / 48°3.48.811.76.7
Apr76° / 55°3.17.912.87.3
May82° / 64°3.210.313.76.1
Jun87° / 71°5.816.914.13.8
Jul90° / 74°6.119143.1
Aug88° / 73°6.61913.23.5
Sep84° / 68°4.912.612.25.3
Oct76° / 57°3.77.611.27.3
Nov68° / 47°2.56.610.37.0
Dec61° / 42°3.47.99.95.4

Cloud cover in May

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 36% of the time in May.

Beyond those clear spells, partly cloudy skies cover about 22% of May, with mostly cloudy or overcast conditions the remaining 42%. Skies tend to cloud over as the month goes on.

0%25%50%75%100%151015202531
Clearer (%)Cloudier (%)
16040
26040
36040
45941
56040
66040
76040
86040
95941
105941
116040
126040
135941
146040
156040
165941
176040
185941
195941
205842
215743
225743
235644
245545
255545
265446
275347
285347
295149
305149
314951

Chance of precipitation in May

Any precipitation

Summerville gets around 3.2 in of rain over 10.3 wet days in May. The line is the day-by-day chance of measurable precipitation.

Day to day, the chance of measurable rain averages around 33% and peaks near 46% on the wettest days. The odds climb toward the end of the month.

0%20%40%60%151015202531
Rain chance (%)
126
226
326
426
526
626
727
827
928
1029
1129
1230
1330
1431
1532
1632
1733
1834
1935
2036
2136
2237
2338
2439
2540
2640
2741
2842
2944
3045
3146

Humidity in May

DryComfortableHumidMuggyOppressiveMiserable

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

By dew point, May lands in the muggy band about 30% of days. Sticky, muggy-or-worse air turns up on roughly 40% of them.

0%25%50%75%100%151015202531
Dry (%)Comfortable (%)Humid (%)Muggy (%)Oppressive (%)
1362324162
2352224172
3332225182
4322225192
5312126202
6292126212
7282126222
8272027233
9262027253
10251927263
11241927274
12231827284
13221827294
14221726305
15211726316
16201625327
17191625327
18181625338
191716243410
201615243411
211515233512
221415233513
231315233515
241114223616
251014223718
26913223719
27813213721
28712213723
29612203726
30511193728
31410193630

Wind in May

Winds average 6 mph in May.

Across May, daily wind ranges from about 6 mph on the calmest days to 7 mph at its breeziest. It stays fairly steady from day to day.

0246810151015202531
Wind speed (mph)Feels
17calm
27calm
37calm
47calm
57calm
67calm
77calm
87calm
96calm
106calm
116calm
126calm
136calm
146calm
156calm
166calm
176calm
186calm
196calm
206calm
216calm
226calm
236calm
246calm
256calm
266calm
276calm
286calm
296calm
306calm
316calm

Sunrise & sunset in May

DaylightNight

Daylight runs from about 13 h 18 min at the start of May to 14 hours by month's end. The lit band spans sunrise to sunset each day.

Days grow by about 42 minutes over May. Sunrise moves from 5:39 AM to 5:18 AM, and sunset from 6:57 PM to 7:18 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202531
Daylight (h)Sunrise (AM)Sunset (PM)
113.35:396:57
213.35:386:57
313.35:376:58
413.45:366:59
513.45:357:00
613.45:347:00
713.55:337:01
813.55:327:02
913.55:327:03
1013.55:317:03
1113.65:307:04
1213.65:297:05
1313.65:287:06
1413.65:287:06
1513.75:277:07
1613.75:267:08
1713.75:257:09
1813.75:257:09
1913.85:247:10
2013.85:237:11
2113.85:237:11
2213.85:227:12
2313.95:227:13
2413.95:217:14
2513.95:217:14
2613.95:207:15
2713.95:207:16
2813.95:197:16
2914.05:197:17
3014.05:187:17
3114.05:187:18

Solar energy in May

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in May, about 6.29 kWh/m² — the sunniest month for solar.

For context, solar energy here swings from a low near 2.56 kWh/m² to a high of 6.29 kWh/m² in May across the year — May's 6.29 kWh/m² sits near the top of that range.

0246151015202531
Solar energy (kWh/m²)Level
16.2Intense
26.2Intense
36.2Intense
46.3Intense
56.3Intense
66.3Intense
76.3Intense
86.3Intense
96.3Intense
106.3Intense
116.3Intense
126.3Intense
136.3Intense
146.3Intense
156.3Intense
166.3Intense
176.3Intense
186.3Intense
196.3Intense
206.3Intense
216.3Intense
226.3Intense
236.3Intense
246.3Intense
256.2Intense
266.2Intense
276.2Intense
286.2Intense
296.2Intense
306.2Intense
316.1Intense
Planning a trip in May

Hazard calendar for Summerville

In seasonPeak

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

Summerville 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 May a good time to visit Summerville?

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

6.1
Sightseeing
5th-best month of the year
6.8
Beach & pool
1st-best month of the year

May is a reasonable time to visit Summerville for sightseeing. The water and warmth also suit a beach or pool day.

What to pack for Summerville in May

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

In May, Summerville sees daytime highs around 82°F and nights near 64°F. Pack light clothes and sun protection. Worth having: rain gear. About 10 days see rain.

light clothessun protectionrain gear

Sea temperature near Summerville in May

The nearest coast averages about 73°F in May — the other half of the beach question. The full-year curve and swim-comfort zones are below.

The sea at the nearest coast (about 27 mi away) is warmest in August at about 83°F and coldest in February near 59°F.

It's comfortable for a long swim from Apr 25 to Nov 14 — about 6.7 months when the water holds above 68°F.

60°70°80°90°JanFebMarAprMayJunJulAugSepOctNovDecbracingcoolrefreshingwarmtropicalcomfortable to swim
Sea temperature (°F)Comfort
Jan60Cool
Feb59Cool
Mar61Cool
Apr66Cool
May73Refreshing
Jun80Warm
Jul83Tropical
Aug83Tropical
Sep81Warm
Oct75Refreshing
Nov67Cool
Dec63Cool

UV index in Summerville in May

LowModerateHighVery highExtreme

Clear-sky midday UV in May peaks around 8 (very high — sun protection essential). The full-year curve, shaded by WHO exposure level, is below.

Under clear skies, the midday UV index in Summerville peaks around July 13 at about 9 (very high) — 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 — in 11 months of the year.

025710JanFebMarAprMayJunJulAugSepOctNovDecModerateHighVery highHighModerateJul 13UV 9Dec 19UV 3
UV index (midday)Level
Jan3Moderate
Feb5Moderate
Mar6High
Apr7Very high
May8Very high
Jun9Very high
Jul10Very high
Aug9Very high
Sep7Very high
Oct5High
Nov4Moderate
Dec3Moderate

Air quality in Summerville in May

GoodModeratePoorUnhealthyVery unhealthy

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

Air quality in Summerville is worst in March — around 20 µg/m³ PM2.5 (moderate), about 2.8× the cleanest month (December, 7 µg/m³).

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

0102030JanFebMarAprMayJunJulAugSepOctNovDecGoodModerateGoodMar 1819 µg/m³Dec 177 µg/m³
PM2.5 (µg/m³)Level
Jan8Good
Feb12Good
Mar20Moderate
Apr14Moderate
May13Moderate
Jun16Moderate
Jul17Moderate
Aug15Moderate
Sep11Good
Oct8Good
Nov8Good
Dec7Good
Location & terrain

Where is Summerville?

Summerville sits at 33.0°N, 80.2°W, 89 ft above sea level, in United States. The nearest listed city is Goose Creek, 8.7 mi away.

Topography around Summerville

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

Within 2 miles, the terrain around Summerville has only modest variations in elevation — a maximum elevation change of 115 ft around an average of 85 ft above sea level; within 10 miles, only modest variations in elevation — a maximum elevation change of 161 ft; within 50 miles, only modest variations in elevation — a maximum elevation change of 299 ft.

The land around Summerville is covered by trees (74%) within 2 miles, trees (79%) within 10 miles, and trees (62%) and water (24%) within 50 miles.

2 miles
115 ft
10 miles
161 ft
50 miles
299 ft
treesgrasslandcroplandartificial surfacesbare terrainwaterwetland
May weather nearby: Goose Creek 8.7 mi · Hanahan 11 mi · North Charleston 16 mi · Charleston 22 mi · Mount Pleasant 24 mi · Sumter 63 mi · Hilton Head 65 mi · Hilton Head Island 66 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 Summerville (33.0185°, -80.1757°, elevation 89 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).