★ January30° · ☂ 18 ★ February30° · ☂ 13 March 31° · ☂ 15 April 31° · ☂ 16 May 32° · ☂ 17 June 31° · ☂ 19 July 31° · ☂ 22 August 31° · ☂ 23 September 31° · ☂ 24 October 31° · ☂ 24 November 31° · ☂ 20 ★ December30° · ☂ 19 Guam in May:very hot, rain on every second day Guam · Records from 2006 to 2025. Not a forecast.
Mean high 32° Hottest day 32.4° (2012)
Mean low 25° Coldest night 23.9° (2006)
Rain days 17 days 7-25 by year
Rainfall 139mm Daylight 12.6 → 12.9 h
Guam's 12 months i Best: December to February
1 2 3 4 5 6 7 8 9 10 11 12
Trip types Beach Poorfrequent rain Sightseeing on foot Poorhot, frequent rain and muggy
Humidity 82% 31 muggy days
Clear days 7 days 9 overcast days
Mean wind 23 km/h 3 windy days
Sea temperature 29° 28.7-29.3° by year (last 6)
Sunrise / sunset (15th) 05:55 / 18:39 Daylight 12.6 → 12.9 h
Guam in May The dry season is ending, but a typhoon can still arrive this month: Typhoon Mawar hit Guam on 24 May 2023 and did heavy damage. Rainy days edge up from April, so keep an eye on the weather news before you go.
Guam in May ran hot: 32°C by day and 25°C at night. By midday the shade was the best seat in town. Rain was a regular part of the month, showing up on 17 days on average. Averages hide a lot here: one year saw 7, another 25.
With 31 days above 30°C on average, most of the month felt like high summer.
Typhoons i 3 of the last 20 years had a tropical storm pass within 300 km this month.
Mawar (2023), 37 km away typhoon strength Dolphin (2015), 52 km away typhoon strength Sanvu (2012), 76 km away tropical storm 1 1 2 1 3 2 4 3 5 1 6 3 7 4 8 4 9 6 10 4 11 1 12
Date by date i Sun
Mon
Tue
Wed
Thu
Fri
Sat
Week
May 1 Saturday 1 rain in 13 of 20 yrs 13/20 31° 25° May 1 rain on 65% of days 31° 25°
May 2 Sunday 2 rain in 12 of 20 yrs 12/20 31° 25° May 3 Monday 3 rain in 9 of 20 yrs 9/20 31° 25° May 4 Tuesday 4 rain in 7 of 20 yrs 7/20 31° 25° May 5 Wednesday 5 rain in 7 of 20 yrs 7/20 31° 26° May 6 Thursday 6 rain in 6 of 20 yrs 6/20 31° 25° May 7 Friday 7 rain in 7 of 20 yrs 7/20 31° 25° May 8 Saturday 8 rain in 12 of 20 yrs 12/20 31° 25° 2-8 rain on 43% of days 31° 25°
May 9 Sunday 9 rain in 9 of 20 yrs 9/20 31° 25° May 10 Monday 10 rain in 10 of 20 yrs 10/20 31° 26° May 11 Tuesday 11 rain in 9 of 20 yrs 9/20 31° 25° May 12 Wednesday 12 rain in 7 of 20 yrs 7/20 31° 25° May 13 Thursday 13 rain in 8 of 20 yrs 8/20 32° 25° May 14 Friday 14 rain in 10 of 20 yrs 10/20 32° 25° May 15 Saturday 15 rain in 14 of 20 yrs 14/20 32° 25° 9-15 rain on 48% of days 31° 25°
May 16 Sunday 16 rain in 13 of 20 yrs 13/20 31° 25° May 17 Monday 17 rain in 14 of 20 yrs 14/20 31° 25° May 18 Tuesday 18 rain in 13 of 20 yrs 13/20 31° 25° May 19 Wednesday 19 rain in 10 of 20 yrs 10/20 31° 25° May 20 Thursday 20 rain in 10 of 20 yrs 10/20 31° 26° May 21 Friday 21 rain in 11 of 20 yrs 11/20 31° 25° May 22 Saturday 22 rain in 12 of 20 yrs 12/20 32° 25° 16-22 rain on 59% of days 31° 25°
May 23 Sunday 23 rain in 9 of 20 yrs 9/20 31° 25° May 24 Monday 24 rain in 10 of 20 yrs 10/20 31° 26° May 25 Tuesday 25 rain in 12 of 20 yrs 12/20 32° 25° May 26 Wednesday 26 rain in 11 of 20 yrs 11/20 32° 25° May 27 Thursday 27 rain in 10 of 20 yrs 10/20 32° 25° May 28 Friday 28 rain in 12 of 20 yrs 12/20 32° 25° May 29 Saturday 29 rain in 14 of 20 yrs 14/20 32° 25° 23-29 rain on 56% of days 32° 25°
May 30 Sunday 30 rain in 16 of 20 yrs 16/20 32° 25° May 31 Monday 31 rain in 15 of 20 yrs 15/20 32° 25°
30-31 rain on 78% of days 32° 25°
May 1 rain on 65% of days 31° 25° 2-8 rain on 43% of days 31° 25° 9-15 rain on 48% of days 31° 25° 16-22 rain on 59% of days 31° 25° 23-29 rain on 56% of days 32° 25° 30-31 rain on 78% of days 32° 25°
Sun
Mon
Tue
Wed
Thu
Fri
Sat
Week
May 1 Monday 1 rain in 13 of 20 yrs 13/20 31° 25° May 2 Tuesday 2 rain in 12 of 20 yrs 12/20 31° 25° May 3 Wednesday 3 rain in 9 of 20 yrs 9/20 31° 25° May 4 Thursday 4 rain in 7 of 20 yrs 7/20 31° 25° May 5 Friday 5 rain in 7 of 20 yrs 7/20 31° 26° May 6 Saturday 6 rain in 6 of 20 yrs 6/20 31° 25° 1-6 rain on 45% of days 31° 25°
May 7 Sunday 7 rain in 7 of 20 yrs 7/20 31° 25° May 8 Monday 8 rain in 12 of 20 yrs 12/20 31° 25° May 9 Tuesday 9 rain in 9 of 20 yrs 9/20 31° 25° May 10 Wednesday 10 rain in 10 of 20 yrs 10/20 31° 26° May 11 Thursday 11 rain in 9 of 20 yrs 9/20 31° 25° May 12 Friday 12 rain in 7 of 20 yrs 7/20 31° 25° May 13 Saturday 13 rain in 8 of 20 yrs 8/20 32° 25° 7-13 rain on 44% of days 31° 25°
May 14 Sunday 14 rain in 10 of 20 yrs 10/20 32° 25° May 15 Monday 15 rain in 14 of 20 yrs 14/20 32° 25° May 16 Tuesday 16 rain in 13 of 20 yrs 13/20 31° 25° May 17 Wednesday 17 rain in 14 of 20 yrs 14/20 31° 25° May 18 Thursday 18 rain in 13 of 20 yrs 13/20 31° 25° May 19 Friday 19 rain in 10 of 20 yrs 10/20 31° 25° May 20 Saturday 20 rain in 10 of 20 yrs 10/20 31° 26° 14-20 rain on 60% of days 31° 25°
May 21 Sunday 21 rain in 11 of 20 yrs 11/20 31° 25° May 22 Monday 22 rain in 12 of 20 yrs 12/20 32° 25° May 23 Tuesday 23 rain in 9 of 20 yrs 9/20 31° 25° May 24 Wednesday 24 rain in 10 of 20 yrs 10/20 31° 26° May 25 Thursday 25 rain in 12 of 20 yrs 12/20 32° 25° May 26 Friday 26 rain in 11 of 20 yrs 11/20 32° 25° May 27 Saturday 27 rain in 10 of 20 yrs 10/20 32° 25° 21-27 rain on 54% of days 32° 25°
May 28 Sunday 28 rain in 12 of 20 yrs 12/20 32° 25° May 29 Monday 29 rain in 14 of 20 yrs 14/20 32° 25° May 30 Tuesday 30 rain in 16 of 20 yrs 16/20 32° 25° May 31 Wednesday 31 rain in 15 of 20 yrs 15/20 32° 25°
28-31 rain on 71% of days 32° 25°
1-6 rain on 45% of days 31° 25° 7-13 rain on 44% of days 31° 25° 14-20 rain on 60% of days 31° 25° 21-27 rain on 54% of days 32° 25° 28-31 rain on 71% of days 32° 25°
Tap another date to change
2006 none
2007 none
2008 10mm
2009 2mm
2010 none
2011 19mm
2012 2mm
2013 6mm
2014 7mm
2015 1mm
2016 none
2017 1mm
2018 1mm
2019 1mm
2020 12mm
2021 13mm
2022 2mm
2023 14mm
2024 1mm
2025 8mm
Holidays in May (2027) 1 Local public holiday or break (busier, pricier)
Your trip dates, the past 20 years Trip dates May 1 (Sat) 2 (Sun) 3 (Mon) 4 (Tue) 5 (Wed) 6 (Thu) 7 (Fri) 8 (Sat) 9 (Sun) 10 (Mon) 11 (Tue) 12 (Wed) 13 (Thu) 14 (Fri) 15 (Sat) 16 (Sun) 17 (Mon) 18 (Tue) 19 (Wed) 20 (Thu) 21 (Fri) 22 (Sat) 23 (Sun) 24 (Mon) 25 (Tue) 26 (Wed) 27 (Thu) 28 (Fri) 29 (Sat) 30 (Sun) 31 (Mon) ~ May 1 (Sat) 2 (Sun) 3 (Mon) 4 (Tue) 5 (Wed) 6 (Thu) 7 (Fri) 8 (Sat) 9 (Sun) 10 (Mon) 11 (Tue) 12 (Wed) 13 (Thu) 14 (Fri) 15 (Sat) 16 (Sun) 17 (Mon) 18 (Tue) 19 (Wed) 20 (Thu) 21 (Fri) 22 (Sat) 23 (Sun) 24 (Mon) 25 (Tue) 26 (Wed) 27 (Thu) 28 (Fri) 29 (Sat) 30 (Sun) 31 (Mon) 1-7 8-14 15-21 22-end Whole month
You can also click two dates on the axis. Hover a cell to see that day's rain. By year Driest trips first
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31
Trip rain days Month rain days Tap a date to start, tap another to end. Each cell is that date in one year. '06 '07 '08 '09 '10 '11 '12 '13 '14 '15 '16 '17 '18 '19 '20 '21 '22 '23 '24 '25
of 20 Dates outside your trip are dimmed.
One row per year, one cell per day. 2010 had 7 rain days, 2012 had 25.
Guam through the year Month High Low Rain days Rainfall Sea January Good 30° 24° 18 days 163mm 29° February Good 30° 24° 13 days 100mm 28° March 31° 24° 15 days 91mm 28° April 31° 25° 16 days 104mm 29° May 32° 25° 17 days 139mm 29° June 31° 25° 19 days 155mm 30° July 31° 25° 22 days 314mm 30° August 31° 25° 23 days 451mm 30° September 31° 25° 24 days 444mm 30° October 31° 25° 24 days 427mm 30° November 31° 25° 20 days 186mm 30° December Good 30° 25° 19 days 121mm 29°
What to pack Loose linen or quick-dry cotton, a wide-brimmed hat and sunscreen were the basics. A water bottle stayed in the bag, and midday plans moved indoors.
With rain every other day, a waterproof jacket is a necessity, not extra luggage. One compact umbrella is enough besides.
Common questions Does it rain a lot in Guam in May? Over the past 20 years May averaged 17 rain days (1 mm or more) out of 31. Individual years ran from 7 in the driest to 25 in the wettest.
What should I wear in Guam in May? Days averaged 32°C and nights 25°C. Pack an umbrella, sandals that can get wet, T-shirts, sunscreen plus a hat, a swimsuit, and insect repellent.
Can you swim in Guam in May? Sea surface temperature averaged 29°C in May, warm enough to stay in for a long swim. Year to year it ranged 28.7-29.3°C. Check local flags for waves and jellyfish on the day.
Is May a good time to visit Guam? On warmth and rain days alone, Guam's easiest months were December to February. May ranked 12 of 12.
Is Guam humid in May? Mean relative humidity was 82%, with about 31 muggy days (dew point of 20°C or more) in the month.
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