May
May · June · September
86climate match
United States · 1991–2020
Best time to visit
West Richland.
May leads for comfortable weather in West Richland: typically 23.2°C by day, 9.2°C at night, with 17 mm of rain. Based on measured 1991–2020 NOAA station history.
Best comfortMay
Typical high23.2°C
Typical low9.2°C
Rain in May17 mm
August
August · July · June
77climate match
May
May · April · October
87climate match
The weakest month is January, scoring 5 against May’s 86 — days reach only 4.5°C, 19° below the 24°C the score treats as ideal.
Month by month
The whole year,
without the guesswork.
The bars show the comfort score. Day and night temperatures come from daily observed highs and lows; rain is the historical monthly estimate.
Jan
54.5° / -2.1°
Feb
188.3° / -1.4°
Mar
4113.8° / 1.7°
Apr
6318.4° / 5.1°
May
8623.2° / 9.2°
Jun
8626.8° / 12.6°
Jul
7232° / 15.7°
Aug
7531.5° / 15.3°
Sep
8626° / 10.9°
Oct
6218° / 5.4°
Nov
249.5° / 0.7°
Dec
54.4° / -2.1°
| Month | Day | Night | Rain | Wet days | Daylight | Comfort | Coverage |
|---|---|---|---|---|---|---|---|
| January | 4.5°C | -2.1°C | 28 mm | 6.6 | 8 h 59 | 5 | Strong coverage |
| February | 8.3°C | -1.4°C | 18 mm | 4.3 | 10 h 15 | 18 | Strong coverage |
| March | 13.8°C | 1.7°C | 17 mm | 4.4 | 11 h 45 | 41 | Strong coverage |
| April | 18.4°C | 5.1°C | 15 mm | 3.9 | 13 h 29 | 63 | Strong coverage |
| May | 23.2°C | 9.2°C | 17 mm | 4.1 | 14 h 57 | 86 | Strong coverage |
| June | 26.8°C | 12.6°C | 13 mm | 2.8 | 15 h 46 | 86 | Strong coverage |
| July | 32°C | 15.7°C | 6 mm | 1.1 | 15 h 27 | 72 | Strong coverage |
| August | 31.5°C | 15.3°C | 3 mm | 1 | 14 h 10 | 75 | Strong coverage |
| September | 26°C | 10.9°C | 7 mm | 1.6 | 12 h 29 | 86 | Strong coverage |
| October | 18°C | 5.4°C | 15 mm | 4.2 | 10 h 49 | 62 | Strong coverage |
| November | 9.5°C | 0.7°C | 22 mm | 5.4 | 9 h 21 | 24 | Strong coverage |
| December | 4.4°C | -2.1°C | 29 mm | 6.5 | 8 h 37 | 5 | Strong coverage |
What has changed
West Richland runs -0.6°C
on the 1961–1990 baseline.
Each bar compares the 2011–2025 daytime average for that month against the same month in 1961–1990, measured at the same station. Months where the older record is too thin to compare are left blank.
Jan
-0.7
Feb
-2.0
Mar
-1.0
Apr
-0.8
May
-0.3
Jun
-0.8
Jul
+0.7
Aug
+0.4
Sep
0.0
Oct
-1.2
Nov
-1.0
Dec
-0.5
| Month | Record high | Record low | Wettest day | Wettest / driest month | Years |
|---|---|---|---|---|---|
| January | 21.7°C31 Jan 1971 | -29.4°C29 Jan 1950 | 24 mm7 Jan 1948 | 77 mm1970 · driest 3 mm in 1947 | 81 |
| February | 22.8°C1 Feb 1971 | -30.0°C2 Feb 1950 | 28 mm21 Feb 1956 | 59 mm1961 · driest 0 mm in 1967 | 80 |
| March | 27.8°C26 Mar 1960 | -13.9°C5 Mar 2019 | 16 mm17 Mar 1954 | 50 mm1957 · driest 1 mm in 1994 | 79 |
| April | 33.3°C30 Apr 1957 | -5.0°C3 Apr 1972 | 18 mm6 Apr 1969 | 41 mm2022 · driest 0 mm in 1949 | 79 |
| May | 40.6°C26 May 1947 | -1.1°C1 May 1954 | 24 mm13 May 2015 | 53 mm1945 · driest 0 mm in 1966 | 81 |
| June | 44.4°C29 Jun 2021 | 3.3°C5 Jun 1984 | 23 mm11 Jun 1948 | 67 mm1948 · driest 0 mm in 2003 | 82 |
| July | 45.0°C30 Jul 2020 | 5.0°C25 Jul 1948 | 23 mm31 Jul 1998 | 41 mm1998 · driest 0 mm in 1962 | 83 |
| August | 45.0°C5 Aug 1961 | 3.9°C19 Aug 1973 | 28 mm30 Aug 1977 | 46 mm1977 · driest 0 mm in 2016 | 80 |
| September | 41.1°C3 Sep 1950 | -0.6°C29 Sep 1983 | 18 mm2 Sep 1971 | 29 mm1959 · driest 0 mm in 1991 | 78 |
| October | 33.9°C6 Oct 2020 | -10.6°C31 Oct 2002 | 28 mm29 Oct 1982 | 61 mm1947 · driest 0 mm in 1978 | 80 |
| November | 25.6°C4 Nov 2020 | -21.1°C23 Nov 1985 | 20 mm20 Nov 1966 | 71 mm1973 · driest 2 mm in 1976 | 81 |
| December | 20.6°C9 Dec 1946 | -23.3°C30 Dec 1968 | 18 mm13 Dec 2003 | 72 mm1973 · driest 1 mm in 1944 | 82 |
| Month | Days 25°C+ | Days 30°C+ | Frost nights | Heavy rain (10 mm+) | Snow days |
|---|---|---|---|---|---|
| January | 0 | 0 | 21 | <1 | <1 |
| February | 0 | 0 | 18 | <1 | <1 |
| March | <1 | 0 | 10 | <1 | <1 |
| April | 2 | <1 | 2 | <1 | 0 |
| May | 11 | 3 | 0 | <1 | 0 |
| June | 20 | 7 | 0 | <1 | 0 |
| July | 30 | 22 | 0 | <1 | 0 |
| August | 29 | 21 | 0 | 0 | 0 |
| September | 18 | 6 | <1 | <1 | 0 |
| October | 2 | <1 | 3 | <1 | 0 |
| November | 0 | 0 | 14 | <1 | <1 |
| December | 0 | 0 | 22 | <1 | <1 |
| Month | Warm & dry days | Wet days | Washouts | Week with 3+ wet days | Daytime mean has ranged |
|---|---|---|---|---|---|
| January | 0% | 19% | 1% | 18% | 0.0–8.7°C |
| February | <1% | 16% | 1% | 14% | 5.6–12.1°C |
| March | 8% | 14% | <1% | 9% | 12.0–16.3°C |
| April | 38% | 11% | <1% | 5% | 17.0–21.9°C |
| May | 74% | 11% | <1% | 8% | 21.4–26.0°C |
| June | 88% | 10% | <1% | 6% | 25.4–30.7°C |
| July | 97% | 3% | <1% | <1% | 30.2–35.2°C |
| August | 96% | 4% | <1% | 1% | 30.0–34.3°C |
| September | 91% | 6% | <1% | 3% | 24.4–29.4°C |
| October | 41% | 11% | <1% | 10% | 17.3–21.8°C |
| November | 2% | 20% | 1% | 20% | 8.0–12.9°C |
| December | <1% | 21% | 1% | 19% | 2.0–7.9°C |
A warm and dry day reaches 20°C with under 1 mm of rain; a wet day gets 1 mm or more; a washout gets 10 mm or more. The week column is the share of seven-day stretches in that month, across the station’s whole daily record, that contained three or more wet days — the odds a week-long trip is rained on repeatedly, counted rather than modelled. The last column is the 10th to 90th percentile of that month’s daytime average across individual years: a narrow band means the average is what you will get, a wide one means the average is a midpoint between years that felt quite different.
The evidence behind this page
Nearby, measured,
and named.
- Place identity
- GeoNames 5815599
- NOAA station
- USC00457015 · RICHLAND
- Station distance
- 7.6 km from the place centre
- Climate period
- 1991–2020
- Minimum month coverage
- 27 usable years
- Daylight
- Calculated from latitude 46.30°, mid-month, sunrise to sunset including refraction. Not a station measurement.
- Important limit
- Historical climate is not a forecast. Nearby stations can miss mountains, coasts, and local microclimates.