Belfast Weather in May
Average highs run from 12°C on May 1 to 15°C on May 31, and lows from 6°C to 8°C. Normal precipitation for the month is 72 mm over about 15 wet days.
May day by day
The normal high and low for each date, in °C.
- Normal low
- Normal high
- Reanalysis extreme high
- Reanalysis extreme low
May at a glance
- Average high
- 14°C
- Average low
- 7°C
- Precipitation
- 72 mm
- Reanalysis high
- 22°CMay 22, 2010
- Reanalysis low
- 1°CMay 3, 1996
- Daylight
- 15 h 13 min to 16 h 52 min
- Cloud cover
- 73%
- Humidity
- 84%
- Dew point
- 8°C
- Wind
- 18.7 km/h
Every day of the month
A wet day has at least 1 mm of precipitation in the reanalysis.
| Date | Normal high | Normal low | Reanalysis high | Reanalysis low | Chance wet |
|---|---|---|---|---|---|
| May 1 | 12°C | 6°C | 18°C 1997 | 2°C 2015 | 50% |
| May 2 | 12°C | 6°C | 19°C 1997 | 1°C 1993 | 50% |
| May 3 | 12°C | 6°C | 18°C 2007 | 1°C 1996 | 48% |
| May 4 | 12°C | 6°C | 19°C 1995 | 2°C 1996 | 48% |
| May 5 | 13°C | 6°C | 17°C 2008 | 2°C 2012 | 48% |
| May 6 | 13°C | 6°C | 19°C 1995 | 1°C 1997 | 48% |
| May 7 | 13°C | 6°C | 19°C 2000 | 3°C 1996 | 48% |
| May 8 | 13°C | 6°C | 19°C 2000 | 3°C 2010 | 48% |
| May 9 | 13°C | 6°C | 20°C 2000 | 2°C 2012 | 47% |
| May 10 | 13°C | 6°C | 18°C 2006 | 1°C 1996 | 48% |
| May 11 | 13°C | 6°C | 20°C 2006 | 2°C 2010 | 50% |
| May 12 | 13°C | 6°C | 19°C 2001 | 2°C 2012 | 52% |
| May 13 | 13°C | 6°C | 18°C 1998 | 2°C 1995 | 52% |
| May 14 | 13°C | 6°C | 18°C 1992 | 1°C 2020 | 53% |
| May 15 | 13°C | 7°C | 18°C 2004 | 3°C 1993 | 53% |
| May 16 | 13°C | 7°C | 19°C 2004 | 2°C 2012 | 51% |
| May 17 | 14°C | 7°C | 19°C 1998 | 2°C 2013 | 50% |
| May 18 | 14°C | 7°C | 20°C 1998 | 1°C 1995 | 50% |
| May 19 | 14°C | 7°C | 21°C 1998 | 3°C 1995 | 49% |
| May 20 | 14°C | 7°C | 20°C 2010 | 4°C 1994 | 50% |
| May 21 | 14°C | 7°C | 19°C 2010 | 4°C 1996 | 51% |
| May 22 | 14°C | 7°C | 22°C 2010 | 3°C 2006 | 52% |
| May 23 | 14°C | 8°C | 20°C 2010 | 3°C 2006 | 51% |
| May 24 | 15°C | 8°C | 21°C 2012 | 4°C 1997 | 51% |
| May 25 | 15°C | 8°C | 20°C 2012 | 3°C 2006 | 51% |
| May 26 | 15°C | 8°C | 20°C 2017 | 4°C 2000 | 51% |
| May 27 | 15°C | 8°C | 20°C 2012 | 4°C 2000 | 50% |
| May 28 | 15°C | 8°C | 21°C 2018 | 4°C 2010 | 50% |
| May 29 | 15°C | 8°C | 20°C 2018 | 4°C 2007 | 50% |
| May 30 | 15°C | 8°C | 21°C 2003 | 4°C 2015 | 50% |
| May 31 | 15°C | 8°C | 21°C 1997 | 3°C 2006 | 50% |
Chance of rain
- Chance of a wet day
Sunrise and sunset
Times for 2026, local time (GMT+1).
- May 1
- sunrise 5:45 AM, sunset 8:58 PM
- May 31
- sunrise 4:56 AM, sunset 9:48 PM
Other months
Sources
Cloud, humidity, wind and sunshine, and temperature and precipitation: NASA POWER (MERRA-2, CERES and GEWEX SRB), 1991-2020. The data was obtained from the National Aeronautics and Space Administration (NASA) Langley Research Center's Prediction Of Worldwide Energy Resources (POWER) project funded through the NASA Earth Science Division: POWER Daily API v2, accessed 2026-09-26. Sun and moon: computed with the NOAA solar equations and Meeus.