Mount Vernon weather in May

In May, Mount Vernon sees average daytime highs of 60°F and overnight lows near 47°F, with 4.1 in of precipitation across 12.8 wet days and about 15 hours of daylight. It is the 5th-warmest and 8th-wettest month of the year here.

Highs climb over the month, from about 57°F in the first days to 62°F by the end. The sky is clear or mostly clear about 21% of the time in May, and the air most often feels dry.

Daylight stretches from about 14 h 18 min at the start of May to 15 h 36 min by month's end. Set against the rest of the year, May is Mount Vernon's 5th-clearest and 8th-windiest month. For the whole year in context, see Mount Vernon's year-round climate.

Daytime high
60°
5th warmest
Overnight low
47°
8th coldest
Precipitation
4.1 in
12.8 wet days
Daylight
15 hours
4:36 AM – 7:35 PM
Cloud cover
66%
5th clearest
Wind
4 mph
8th windiest
Solar energy
5.39 kWh/m²
Travel score
4.4
out of 10

Mount Vernon is city in Skagit County, Washington, United States.

Density
1,050/km²
people per km²
Founded
1870

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 57°F in the first days to 62°F by the end.

A typical May day in Mount Vernon reaches about 60°F in the afternoon and slips back to 47°F overnight — a 13°F spread between the day's warmth and the night's chill. On most days the high lands between 52°F and 69°F. Set against its neighbours, May runs about 6°F warmer than April and about 4°F cooler than June.

30°40°50°60°70°80°151015202531
Avg high (°F)Avg low (°F)
15743
25744
35744
45744
55844
65844
75845
85845
95845
105946
115946
125946
135946
146046
156047
166047
176047
186047
196047
206148
216148
226148
236148
246148
256149
266249
276249
286249
296249
306249
316249

How May really feels in Mount Vernon

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.

Mount Vernon 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
Jan42° / 34°10.219.19.58.60.2
Feb44° / 34°6.715.499.90.7
Mar48° / 37°8.119.79.811.61.4
Apr53° / 41°5.816.6413.42.5
May60° / 47°4.112.80.7154.4
Jun64° / 51°3.110.9015.85.5
Jul70° / 55°1.55.6015.57.4
Aug71° / 56°1.85.7014.17.5
Sep65° / 51°3.99.5012.46.1
Oct55° / 44°7.915.20.710.63.2
Nov46° / 37°11.419.47.791.0
Dec41° / 33°10.01912.28.20.1

Cloud cover in May

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 21% of the time in May.

Beyond those clear spells, partly cloudy skies cover about 15% of May, with mostly cloudy or overcast conditions the remaining 63%.

0%25%50%75%100%151015202531
Clearer (%)Cloudier (%)
13862
23862
33961
43961
53862
63961
73961
84060
94060
103961
113961
123961
133862
143862
153763
163664
173565
183565
193565
203565
213466
223466
233565
243565
253565
263565
273565
283664
293664
303565
313565

Chance of precipitation in May

Any precipitationSnow

Mount Vernon gets around 4.1 in of rain and snow over 12.8 wet days in May. The line is the day-by-day chance of measurable precipitation.

Day to day, the chance of measurable precipitation averages around 41% and peaks near 49% on the wettest days, and about 1 day brings snow. The odds ease toward the end of the month.

0%20%40%60%151015202531
Rain chance (%)Snow chance (%)
1496
2486
3476
4476
5465
6455
7445
8434
9424
10414
11413
12403
13402
14402
15402
16392
17391
18391
19391
20391
21391
22401
23401
24401
25400
26390
27390
28390
29390
30390
31390

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

0%25%50%75%100%151015202531
Dry (%)Comfortable (%)
11000
21000
31000
41000
51000
61000
71000
81000
91000
101000
111000
121000
131000
14991
15991
16991
17991
18991
19991
20991
21991
22982
23982
24982
25982
26973
27973
28973
29964
30964
31964

Wind in May

Winds average 4 mph in May.

Across May, daily wind ranges from about 4 mph on the calmest days to 4 mph at its breeziest. It stays fairly steady from day to day.

0246810151015202531
Wind speed (mph)Feels
14calm
24calm
34calm
44calm
54calm
64calm
74calm
84calm
94calm
104calm
114calm
124calm
134calm
144calm
154calm
164calm
174calm
184calm
194calm
204calm
214calm
224calm
234calm
244calm
254calm
264calm
274calm
284calm
294calm
304calm
314calm

Sunrise & sunset in May

DaylightNight

Daylight runs from about 14 h 18 min at the start of May to 15 h 36 min by month's end. The lit band spans sunrise to sunset each day.

Days grow by about 78 minutes over May. Sunrise moves from 4:59 AM to 4:20 AM, and sunset from 7:14 PM to 7:53 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202531
Daylight (h)Sunrise (AM)Sunset (PM)
114.34:597:14
214.34:577:16
314.44:557:17
414.44:547:19
514.54:527:20
614.54:507:22
714.64:497:23
814.64:477:24
914.74:467:26
1014.74:447:27
1114.84:437:29
1214.84:417:30
1314.94:407:31
1414.94:387:33
1515.04:377:34
1615.04:367:35
1715.04:347:37
1815.14:337:38
1915.14:327:39
2015.24:317:41
2115.24:307:42
2215.24:287:43
2315.34:277:44
2415.34:267:46
2515.44:257:47
2615.44:247:48
2715.44:237:49
2815.54:237:50
2915.54:227:51
3015.54:217:52
3115.64:207:53

Solar energy in May

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in May, about 5.39 kWh/m².

For context, solar energy here swings from a low near 0.85 kWh/m² to a high of 6.27 kWh/m² in July across the year — May's 5.39 kWh/m² falls in the middle.

0246151015202531
Solar energy (kWh/m²)Level
15.1Bright
25.2Bright
35.2Bright
45.2Bright
55.3Bright
65.3Bright
75.3Bright
85.4Bright
95.4Bright
105.4Bright
115.4Bright
125.4Bright
135.4Bright
145.4Bright
155.4Bright
165.4Bright
175.4Bright
185.4Bright
195.4Bright
205.4Bright
215.4Bright
225.4Bright
235.4Bright
245.4Bright
255.4Bright
265.4Bright
275.4Bright
285.4Bright
295.4Bright
305.4Bright
315.4Bright
Planning a trip in May

Hazard calendar for Mount Vernon

In seasonPeak

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

Mount Vernon's rainy season runs October–April, when most of the year's rain falls.

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

Is May a good time to visit Mount Vernon?

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

4.4
Sightseeing
5th-best month of the year
0.4
Beach & pool
5th-best month of the year

May is a reasonable time to visit Mount Vernon for sightseeing.

What to pack for Mount Vernon in May

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

In May, Mount Vernon sees daytime highs around 60°F and nights near 47°F. Worth packing: a warm layer, rain gear and sun protection. About 13 days see rain.

a warm layerrain gearsun protection

Sea temperature near Mount Vernon in May

The nearest coast averages about 50°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 25 mi away) is warmest in August at about 54°F and coldest in February near 46°F.

The water stays below 68°F all year — cool enough that most swimmers want a wetsuit.

45°50°55°JanFebMarAprMayJunJulAugSepOctNovDecbracing
Sea temperature (°F)Comfort
Jan46Bracing
Feb46Bracing
Mar47Bracing
Apr48Bracing
May50Bracing
Jun52Bracing
Jul53Bracing
Aug54Bracing
Sep53Bracing
Oct50Bracing
Nov49Bracing
Dec47Bracing

UV index in Mount Vernon in May

LowModerateHighVery highExtreme

Clear-sky midday UV in May peaks around 7 — enough to warrant sun protection. The full-year curve, shaded by WHO exposure level, is below.

Under clear skies, the midday UV index in Mount Vernon peaks around July 17 at about 8 (very high) — sunscreen and a hat are worth it in the middle of the day. It bottoms out near December 18 at about 1 (low).

The index reaches 3 or more — the level where the WHO recommends sun protection — in 7 months of the year.

025710JanFebMarAprMayJunJulAugSepOctNovDecLowModerateHighVery highHighModerateLowJul 17UV 8Dec 18UV 1
UV index (midday)Level
Jan1Low
Feb1Low
Mar4Moderate
Apr5Moderate
May7High
Jun6High
Jul8Very high
Aug6High
Sep4Moderate
Oct3Moderate
Nov1Low
Dec1Low

Air quality in Mount Vernon 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 Mount Vernon is worst in September — around 18 µg/m³ PM2.5 (moderate), about 3.2× the cleanest month (December, 6 µg/m³).

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

0102030JanFebMarAprMayJunJulAugSepOctNovDecGoodModerateGoodSep 1018 µg/m³Dec 176 µg/m³
PM2.5 (µg/m³)Level
Jan7Good
Feb9Good
Mar12Good
Apr12Good
May12Good
Jun11Good
Jul11Good
Aug18Moderate
Sep18Moderate
Oct12Good
Nov7Good
Dec6Good
Location & terrain

Where is Mount Vernon?

Mount Vernon sits at 48.4°N, 122.3°W, 95 ft above sea level, in United States. The nearest listed city is Anacortes, 14 mi away.

Topography around Mount Vernon

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

Within 2 miles, the terrain around Mount Vernon has significant variations in elevation — a maximum elevation change of 938 ft around an average of 89 ft above sea level; within 10 miles, very significant variations in elevation — a maximum elevation change of 4,045 ft; within 50 miles, extreme variations in elevation — a maximum elevation change of 10,755 ft.

The land around Mount Vernon is covered by trees (29%), grassland (28%) and artificial surfaces (27%) within 2 miles, trees (41%) and grassland (25%) within 10 miles, and trees (57%) and water (29%) within 50 miles.

2 miles
938 ft
10 miles
4,045 ft
50 miles
10,755 ft
treesgrasslandcroplandartificial surfacesbare terrainsnow and icewaterwetland
May weather nearby: Anacortes 14 mi · Oak Harbor 17 mi · Arlington 18 mi · Bellingham 24 mi · Marysville 27 mi · Lake Stevens 30 mi · Everett 31 mi · West Lake Stevens 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 Mount Vernon (48.4212°, -122.3341°, elevation 95 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. 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).