Dover weather in May

In May, Dover sees average daytime highs of 72°F and overnight lows near 57°F, with 3.4 in of rain across 10.7 wet days and about 14.1 hours of daylight. It is the 5th-warmest and 8th-wettest month of the year here.

Highs climb over the month, from about 69°F in the first days to 76°F by the end. The sky is clear or mostly clear about 28% of the time in May, and the air most often feels dry.

Daylight stretches from about 13 h 36 min at the start of May to 14 h 30 min by month's end. Set against the rest of the year, May is Dover's 11th-clearest and 8th-windiest month. For the whole year in context, see Dover's year-round climate.

Daytime high
72°
5th warmest
Overnight low
57°
8th coldest
Rainfall
3.4 in
10.7 wet days
Daylight
14 h 06 min
4:54 AM – 7:02 PM
Cloud cover
61%
11th clearest
Wind
8 mph
8th windiest
Solar energy
5.93 kWh/m²
Travel score
6.6
out of 10

Dover is capital city of the U.S. state of Delaware and seat of Kent County.

Density
648/km²
people per km²
Founded
1683

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 69°F in the first days to 76°F by the end.

A typical May day in Dover reaches about 72°F in the afternoon and slips back to 57°F overnight — a 15°F spread between the day's warmth and the night's chill. On most days the high lands between 62°F and 83°F. Set against its neighbours, May runs about 9°F warmer than April and about 9°F cooler than June.

40°60°80°151015202531
Avg high (°F)Avg low (°F)
16852
26853
36953
46953
56953
66954
76954
87054
97055
107055
117155
127155
137156
147156
157256
167256
177257
187357
197357
207358
217458
227458
237459
247559
257560
267560
277660
287661
297661
307762
317762

How May really feels in Dover

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.

Dover weather by month

How May compares with the rest of the year at a glance. May is the 5th-warmest and 8th-wettest month here — the current month is highlighted below.

MonthHigh / Low (°F)Rainfall (inches)Wet daysSnow daysDaylight (hours)Travel score
Jan43° / 30°3.19.22.99.60.4
Feb45° / 31°3.08.92.910.51.0
Mar53° / 38°4.110.31.611.72.9
Apr64° / 47°3.39.90.2135.6
May72° / 57°3.410.7014.16.6
Jun81° / 66°3.610.2014.76.2
Jul85° / 71°3.711014.55.2
Aug83° / 70°4.310.5013.55.8
Sep77° / 63°4.19.2012.37.0
Oct67° / 52°3.780116.5
Nov56° / 42°2.97.50.29.94.0
Dec47° / 35°3.79.11.39.31.6

Cloud cover in May

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 28% of the time in May.

Beyond those clear spells, partly cloudy skies cover about 17% of May, with mostly cloudy or overcast conditions the remaining 55%.

0%25%50%75%100%151015202531
Clearer (%)Cloudier (%)
14555
24555
34555
44654
54555
64555
74555
84555
94555
104555
114555
124555
134555
144555
154456
164456
174456
184456
194456
204555
214555
224555
234555
244654
254654
264654
274654
284753
294753
304654
314654

Chance of precipitation in May

Any precipitation

Dover gets around 3.4 in of rain over 10.7 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 34% and peaks near 36% on the wettest days.

0%10%20%30%40%50%151015202531
Rain chance (%)
133
233
333
433
533
634
734
834
935
1035
1136
1236
1336
1436
1536
1636
1736
1835
1935
2035
2135
2235
2334
2434
2533
2633
2733
2833
2932
3032
3132

Humidity in May

DryComfortableHumidMuggyOppressiveMiserable

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

By dew point, May lands in the dry band about 60% of days. Sticky, muggy-or-worse air turns up on roughly 7% of them.

0%25%50%75%100%151015202531
Dry (%)Comfortable (%)Humid (%)Muggy (%)Oppressive (%)
18014510
27815610
37715710
47616710
57417810
67317910
77317910
870181020
969181120
1069181120
1167181230
1266181330
1366181330
1464181440
1564181440
1661191550
1759191660
1858191670
1957191770
2055191880
2154191890
22521919100
23501919120
24482020130
25462020131
26452020141
27432021151
28412121161
29402121171
30392121181
31382121191

Wind in May

Winds average 8 mph in May.

Across May, 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.

051015151015202531
Wind speed (mph)Feels
18light breeze
28light breeze
38light breeze
48light breeze
58light breeze
68light breeze
78light breeze
88light breeze
98light breeze
108light breeze
118light breeze
128light breeze
138light breeze
148light breeze
158light breeze
168light breeze
178light breeze
188light breeze
198light breeze
208light breeze
218light breeze
228light breeze
238light breeze
247light breeze
257calm
267calm
277calm
287calm
297calm
307calm
317calm

Sunrise & sunset in May

DaylightNight

Daylight runs from about 13 h 36 min at the start of May to 14 h 30 min by month's end. The lit band spans sunrise to sunset each day.

Days grow by about 54 minutes over May. Sunrise moves from 5:11 AM to 4:44 AM, and sunset from 6:48 PM to 7:15 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202531
Daylight (h)Sunrise (AM)Sunset (PM)
113.65:116:48
213.75:096:49
313.75:086:50
413.75:076:51
513.85:066:52
613.85:056:53
713.85:036:54
813.95:026:55
913.95:016:56
1013.95:006:57
1114.04:596:58
1214.04:586:59
1314.04:577:00
1414.14:567:01
1514.14:557:02
1614.14:547:02
1714.24:537:03
1814.24:527:04
1914.24:527:05
2014.34:517:06
2114.34:507:07
2214.34:497:08
2314.34:497:09
2414.44:487:10
2514.44:477:10
2614.44:477:11
2714.44:467:12
2814.54:457:13
2914.54:457:14
3014.54:447:14
3114.54:447:15

Solar energy in May

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in May, about 5.93 kWh/m².

For context, solar energy here swings from a low near 1.93 kWh/m² to a high of 6.33 kWh/m² in June across the year — May's 5.93 kWh/m² sits near the top of that range.

0246151015202531
Solar energy (kWh/m²)Level
15.7Bright
25.7Bright
35.7Bright
45.8Bright
55.8Bright
65.8Bright
75.8Bright
85.8Bright
95.8Bright
105.8Bright
115.8Bright
125.8Bright
135.9Bright
145.9Bright
155.9Bright
165.9Bright
175.9Bright
185.9Bright
196.0Bright
206.0Bright
216.0Bright
226.0Intense
236.0Intense
246.0Intense
256.1Intense
266.1Intense
276.1Intense
286.1Intense
296.1Intense
306.1Intense
316.2Intense
Planning a trip in May

Hazard calendar for Dover

In seasonPeak

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

Dover 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 Dover?

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

6.6
Sightseeing
2nd-best month of the year
4.7
Beach & pool
5th-best month of the year

May is a reasonable time to visit Dover for sightseeing.

What to pack for Dover in May

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

In May, Dover sees daytime highs around 72°F and nights near 57°F. Worth packing: light clothes, rain gear and sun protection. About 11 days see rain.

light clothesrain gearsun protection

Sea temperature near Dover in May

The nearest coast averages about 58°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 8 mi away) is warmest in August at about 76°F and coldest in February near 37°F.

It's comfortable for a long swim from Jun 19 to Oct 3 — about 3.5 months when the water holds above 68°F.

30°40°50°60°70°80°JanFebMarAprMayJunJulAugSepOctNovDecbracingcoolrefreshingwarmtropicalcomfortable to swim
Sea temperature (°F)Comfort
Jan39Bracing
Feb37Bracing
Mar41Bracing
Apr49Bracing
May58Bracing
Jun67Cool
Jul74Refreshing
Aug76Warm
Sep73Refreshing
Oct64Cool
Nov53Bracing
Dec44Bracing

UV index in Dover 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 Dover peaks around July 10 at about 8 (very high) — sunscreen, a hat and midday shade are essential. It bottoms out near December 20 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 8Dec 20UV 2
UV index (midday)Level
Jan2Low
Feb3Moderate
Mar5Moderate
Apr6High
May8Very high
Jun8Very high
Jul9Very high
Aug6High
Sep6High
Oct4Moderate
Nov3Moderate
Dec2Low

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

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

01020JanFebMarAprMayJunJulAugSepOctNovDecGoodModerateGoodJul 1115 µg/m³Nov 127 µg/m³
PM2.5 (µg/m³)Level
Jan9Good
Feb11Good
Mar12Good
Apr12Good
May13Moderate
Jun15Moderate
Jul16Moderate
Aug13Moderate
Sep10Good
Oct8Good
Nov7Good
Dec8Good
Location & terrain

Where is Dover?

Dover sits at 39.2°N, 75.5°W, 30 ft above sea level, in United States. The nearest listed city is Middletown, 22 mi away.

Topography around Dover

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

Within 2 miles, the terrain around Dover has only modest variations in elevation — a maximum elevation change of 131 ft around an average of 39 ft above sea level; within 10 miles, only modest variations in elevation — a maximum elevation change of 174 ft; within 50 miles, only modest variations in elevation — a maximum elevation change of 761 ft.

The land around Dover is covered by trees (41%), artificial surfaces (29%) and grassland (21%) within 2 miles, trees (30%) and cropland (26%) within 10 miles, and trees (39%), water (27%) and cropland (20%) within 50 miles.

2 miles
131 ft
10 miles
174 ft
50 miles
761 ft
treesgrasslandcroplandartificial surfacesbare terrainwaterwetland
May weather nearby: Middletown 22 mi · Bridgeton 24 mi · Millville 31 mi · South Vineland 33 mi · Bear 34 mi · Vineland 35 mi · Elkton 35 mi · Cape May 37 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 Dover (39.1582°, -75.5244°, elevation 30 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).