Climate averages 1991–2020
Meridian weather
in May.
A mild, fairly dry month: the 5th warmest and the 8th driest of the year. Meets the pleasant-weather rule
Long-term climate patterns, not a forecast for a particular trip.
May is a mild month in Meridian: daytime highs average 21.8°C and nights cool to about 8.6°C. By daytime temperature it is the 5th warmest of the 12 months.
Expect about 29 mm of rain on roughly 6 days, which makes May a fairly dry month (the 8th driest of the 12 months). Daylight, from sunrise to sunset, lasts about 14 h 41 min on an average May day.
The nearest other city in this atlas is Boise (15 km away). In May its highs average 21.6°C, about as warm as Meridian, with 31 mm of rain.
Among the 498 cities listed in the United States, Meridian ranks joint 308th of 498 for the warmest May highs and joint 125th of 498 for the driest May (rainfall, lowest first). The mean May high of those 498 cities is 23.8°C; Meridian is 2.0°C cooler than that mean.
From May to June, average highs rise by 4.9°C to 26.6°C, and monthly rainfall falls from 29 mm to 16 mm.
The annual picture
May in context
Monthly rainfall
Average total · mmAverages from hourly ERA5 reanalysis data. Actual weather varies from year to year. How these numbers are calculated
Every month, side by side
Meridian climate table
| Month | Average highHigh / low | Average low | Rainfall mm/month | Rain days ≥1 mm/day | Daylight hours/dayDaylight h/day |
|---|---|---|---|---|---|
| January | 3.8°C-4.3°C | -4.3°C | 40 | 9.0 | 9.39 h |
| February | 7.0°C-2.5°C | -2.5°C | 26 | 7.4 | 10.510 h |
| March | 12.1°C0.8°C | 0.8°C | 31 | 8.6 | 11.912 h |
| April | 16.1°C3.8°C | 3.8°C | 28 | 6.4 | 13.413 h |
| May, selected | 21.8°C8.6°C | 8.6°C | 29 | 5.9 | 14.715 h |
| June | 26.6°C13.1°C | 13.1°C | 16 | 3.4 | 15.415 h |
| July | 32.7°C18.1°C | 18.1°C | 3.4 | 1.0 | 15.115 h |
| August | 31.8°C17.4°C | 17.4°C | 3.4 | 0.9 | 14.014 h |
| September | 26.1°C12.4°C | 12.4°C | 9.8 | 2.0 | 12.613 h |
| October | 17.6°C6.0°C | 6.0°C | 20 | 4.2 | 11.111 h |
| November | 9.3°C0.0°C | 0.0°C | 30 | 7.3 | 9.710 h |
| December | 3.6°C-3.8°C | -3.8°C | 42 | 9.3 | 9.09 h |
Rainfall is the average of the 30 separate monthly totals. A rain day is a local calendar day with at least 1 mm of precipitation. Daylight is the calculated sunrise-to-sunset length, not measured sunshine.
Compare places
May in nearby cities
- Boise in MayUnited States · 15 kmHigh 21.6°C · Low 8.5°C · 31 mm rain
- Nampa in MayUnited States · 16 kmHigh 22.4°C · Low 9.8°C · 29 mm rain
- Kennewick in MayUnited States · 361 kmHigh 24.8°C · Low 11.4°C · 18 mm rain
- Tri-Cities in MayUnited States · 367 kmHigh 25.0°C · Low 11.5°C · 18 mm rain
- Bend in MayUnited States · 398 kmHigh 16.9°C · Low 4.4°C · 45 mm rain
- Missoula in MayUnited States · 408 kmHigh 17.9°C · Low 6.3°C · 56 mm rain
- Ogden in MayUnited States · 449 kmHigh 19.6°C · Low 7.4°C · 59 mm rain
- Spokane Valley in MayUnited States · 456 kmHigh 19.2°C · Low 7.0°C · 51 mm rain
Read the numbers correctly
Climate, not a promise.
These patterns help compare months. They cannot tell you the weather on a specific day of your trip.
Sources, method and limitsHow these numbers are made (what the highs, lows and rain days mean, the sources and the model cell used for Meridian) is explained once on the Meridian year overview and on the Sources, method and limits page.
Nampa lies in the same rainfall cell, so its rainfall figures are identical to these; temperatures differ because they come from smaller 0.1° cells.