Portland weather in May

In May, Portland sees average daytime highs of 83°F and overnight lows near 73°F, with 2.7 in of rain across 8.8 wet days and about 13.4 hours of daylight. It is the 5th-warmest and 4th-wettest month of the year here.

Highs climb over the month, from about 81°F in the first days to 85°F by the end. The sky is clear or mostly clear about 40% of the time in May, and the air most often feels oppressive.

Daylight stretches from about 13 hours at the start of May to 13 h 36 min by month's end. Set against the rest of the year, May is Portland's 7th-clearest and 1st-windiest month. For the whole year in context, see Portland's year-round climate.

Daytime high
83°
5th warmest
Overnight low
73°
8th coldest
Rainfall
2.7 in
8.8 wet days
Daylight
13 h 24 min
5:44 AM – 7:07 PM
Cloud cover
50%
7th clearest
Wind
12 mph
1st windiest
Solar energy
6.13 kWh/m²
Travel score
6.1
out of 10

Portland is city in Texas, United States.

Density
580/km²
people per km²

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 81°F in the first days to 85°F by the end.

A typical May day in Portland reaches about 83°F in the afternoon and slips back to 73°F overnight — a 11°F spread between the day's warmth and the night's chill. On most days the high lands between 79°F and 87°F. Set against its neighbours, May runs about 5°F warmer than April and about 4°F cooler than June.

60°70°80°90°151015202531
Avg high (°F)Avg low (°F)
18170
28170
38170
48170
58171
68271
78271
88271
98271
108272
118272
128372
138372
148372
158373
168373
178373
188373
198473
208474
218474
228474
238474
248574
258575
268575
278575
288575
298575
308676
318676

How May really feels in Portland

Once humidity and wind are folded in, May averages 10 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
10
heat index over the day's high
Days feeling ≤ 32°F
0
wind chill below the day's low

The story in May is heat — humidity pushes the afternoon "feels like" well above the raw temperature.

Portland weather by month

How May compares with the rest of the year at a glance. May is the 5th-warmest and 4th-wettest month here — the current month is highlighted below.

MonthHigh / Low (°F)Rainfall (inches)Wet daysDaylight (hours)Travel score
Jan65° / 51°2.16.510.46.5
Feb68° / 54°1.55.2116.9
Mar73° / 60°2.26.211.87.4
Apr78° / 66°2.06.412.67.4
May83° / 73°2.78.813.46.1
Jun87° / 77°2.910.213.74.8
Jul89° / 78°2.28.613.64.5
Aug89° / 78°2.39.7134.2
Sep87° / 75°4.313.812.24.5
Oct81° / 67°3.48.811.36.8
Nov73° / 59°2.26.810.67.4
Dec67° / 52°2.16.310.36.7

Cloud cover in May

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 40% of the time in May.

Beyond those clear spells, partly cloudy skies cover about 25% of May, with mostly cloudy or overcast conditions the remaining 35%. Skies tend to open up as the month goes on.

0%25%50%75%100%151015202531
Clearer (%)Cloudier (%)
15743
25743
35743
45842
55842
65842
75842
85941
95941
105941
116139
126139
136238
146337
156535
166535
176634
186733
196832
206832
216931
226931
237030
247030
257129
267228
277228
287228
297228
307426
317426

Chance of precipitation in May

Any precipitation

Portland gets around 2.7 in of rain over 8.8 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 28% and peaks near 30% on the wettest days.

0%10%20%30%40%151015202531
Rain chance (%)
124
224
325
425
526
626
727
827
927
1027
1127
1228
1328
1428
1528
1628
1728
1828
1928
2029
2129
2229
2329
2429
2529
2630
2730
2830
2930
3030
3130

Humidity in May

DryComfortableHumidMuggyOppressiveMiserable

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

By dew point, May lands in the oppressive band about 54% of days. Sticky, muggy-or-worse air turns up on roughly 86% of them.

0%25%50%75%100%151015202531
Dry (%)Comfortable (%)Humid (%)Muggy (%)Oppressive (%)Miserable (%)
1791321454
2791221465
3781221475
4681120486
5671120496
6571020517
7561020527
8561020518
9451020538
1045920539
1134920559
12349195510
13339195511
14239195512
15239195413
16238185514
17238185415
18228175516
19227165617
20127165618
21126155620
22126145621
23125135623
24115135624
25114125626
26113115727
27013105729
28012105730
2901295731
3001285732
3100185734

Wind in May

Winds average 12 mph in May, the windiest month of the year.

Across May, daily wind ranges from about 11 mph on the calmest days to 12 mph at its breeziest. It stays fairly steady from day to day.

051015151015202531
Wind speed (mph)Feels
112light breeze
212light breeze
312light breeze
412light breeze
512light breeze
612light breeze
712light breeze
812light breeze
912light breeze
1012light breeze
1112light breeze
1212light breeze
1312light breeze
1412light breeze
1512light breeze
1612light breeze
1712light breeze
1812light breeze
1912light breeze
2012light breeze
2112light breeze
2212light breeze
2312light breeze
2412light breeze
2512light breeze
2612light breeze
2711light breeze
2811light breeze
2911light breeze
3011light breeze
3111light breeze

Sunrise & sunset in May

DaylightNight

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

Days grow by about 36 minutes over May. Sunrise moves from 5:55 AM to 5:38 AM, and sunset from 6:58 PM to 7:15 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202531
Daylight (h)Sunrise (AM)Sunset (PM)
113.05:556:58
213.15:546:59
313.15:536:59
413.15:537:00
513.15:527:00
613.25:517:01
713.25:507:01
813.25:497:02
913.25:497:03
1013.35:487:03
1113.35:477:04
1213.35:477:04
1313.35:467:05
1413.35:457:06
1513.45:457:06
1613.45:447:07
1713.45:447:07
1813.45:437:08
1913.45:437:09
2013.55:427:09
2113.55:427:10
2213.55:417:10
2313.55:417:11
2413.55:407:11
2513.55:407:12
2613.65:407:13
2713.65:397:13
2813.65:397:14
2913.65:397:14
3013.65:387:15
3113.65:387:15

Solar energy in May

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in May, about 6.13 kWh/m².

For context, solar energy here swings from a low near 2.76 kWh/m² to a high of 6.6 kWh/m² in July across the year — May's 6.13 kWh/m² falls in the middle.

0246151015202531
Solar energy (kWh/m²)Level
15.9Bright
25.9Bright
35.9Bright
46.0Bright
56.0Bright
66.0Bright
76.0Bright
86.0Intense
96.0Intense
106.0Intense
116.0Intense
126.1Intense
136.1Intense
146.1Intense
156.1Intense
166.2Intense
176.2Intense
186.2Intense
196.2Intense
206.2Intense
216.2Intense
226.3Intense
236.3Intense
246.3Intense
256.3Intense
266.3Intense
276.3Intense
286.3Intense
296.3Intense
306.4Intense
316.4Intense
Planning a trip in May

Hazard calendar for Portland

In seasonPeak

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

Portland 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 Portland?

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

6.1
Sightseeing
8th-best month of the year
7.2
Beach & pool
1st-best month of the year

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

What to pack for Portland in May

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

In May, Portland sees daytime highs around 83°F and nights near 73°F. Pack light clothes and sun protection. Worth having: rain gear. About 9 days see rain.

light clothessun protectionrain gear

Sea temperature near Portland in May

The nearest coast averages about 77°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 21 mi away) is warmest in September at about 84°F and coldest in February near 64°F.

It's comfortable for a long swim from Mar 29 to Dec 20 — about 8.8 months when the water holds above 68°F.

60°70°80°90°JanFebMarAprMayJunJulAugSepOctNovDeccoolrefreshingwarmtropicalcomfortable to swim
Sea temperature (°F)Comfort
Jan65Cool
Feb64Cool
Mar66Cool
Apr71Refreshing
May77Warm
Jun82Tropical
Jul83Tropical
Aug84Tropical
Sep84Tropical
Oct80Warm
Nov73Refreshing
Dec69Refreshing

UV index in Portland in May

LowModerateHighVery highExtreme

Clear-sky midday UV in May peaks around 11 (very high — sun protection essential). The full-year curve, shaded by WHO exposure level, is below.

Under clear skies, the midday UV index in Portland peaks around June 16 at about 11 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near December 21 at about 4 (moderate).

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

025710JanFebMarAprMayJunJulAugSepOctNovDecModerateHighVery highExtremeVery highHighModerateJun 16UV 11Dec 21UV 4
UV index (midday)Level
Jan5Moderate
Feb6High
Mar7High
Apr10Very high
May11Extreme
Jun11Extreme
Jul11Extreme
Aug11Extreme
Sep10Very high
Oct7High
Nov5High
Dec4Moderate

Air quality in Portland 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 Portland is worst in July — around 20 µg/m³ PM2.5 (moderate), about 3.2× the cleanest month (November, 6 µg/m³).

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

0102030JanFebMarAprMayJunJulAugSepOctNovDecGoodModerateGoodJul 1419 µg/m³Nov 116 µg/m³
PM2.5 (µg/m³)Level
Jan8Good
Feb9Good
Mar12Good
Apr12Good
May16Moderate
Jun17Moderate
Jul20Moderate
Aug13Moderate
Sep11Good
Oct6Good
Nov6Good
Dec7Good
Location & terrain

Where is Portland?

Portland sits at 27.9°N, 97.3°W, 43 ft above sea level, in United States. The nearest listed city is Corpus Christi, 6.8 mi away.

Topography around Portland

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

Within 2 miles, the terrain around Portland has only modest variations in elevation — a maximum elevation change of 56 ft around an average of 16 ft above sea level; within 10 miles, only modest variations in elevation — a maximum elevation change of 115 ft; within 50 miles, only modest variations in elevation — a maximum elevation change of 394 ft.

The land around Portland is covered by water (47%) and artificial surfaces (25%) within 2 miles, water (38%) and cropland (33%) within 10 miles, and water (33%), grassland (23%) and cropland (20%) within 50 miles.

2 miles
56 ft
10 miles
115 ft
50 miles
394 ft
treesgrasslandcroplandartificial surfacesbare terrainwaterwetland
May weather nearby: Corpus Christi 6.8 mi · Kingsville 41 mi · Alice 47 mi · Victoria 67 mi · Bay City 112 mi · Harlingen 119 mi · Edinburg 121 mi · San Benito 122 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 Portland (27.8773°, -97.3239°, elevation 43 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).