Washington climate

Washington is warmest in July, with average highs of 31 °C, and coldest in January, when nights average -1.9 °C. September is the wettest month (116 mm) and February the driest (73 mm). Figures are 1991–2020 climate normals.

Across a full year Washington averages 1,113 mm of rain, 124 days above 25 °C and 71 days below freezing.

United States · 7 m elevation · population 689,545 · 1991–2020 normals

  1. Jan
  2. Feb
  3. Mar
  4. Apr 13°
  5. May 18°
  6. Jun 23°
  7. Jul 26°
  8. Aug 25°
  9. Sep 21°
  10. Oct 15°
  11. Nov
  12. Dec

Temperature below 0 °C to above 30 °C Rain band height is that month’s share of the wettest month

What to expectWashington through the year

Washington has a clear annual cycle: average daily highs run from 6.3 °C in January to 31 °C in July, a swing of 24 °C in mean temperature across the year.

Counted across a normal year, 124 days a year reach 25 °C, 53 of them reach 30 °C, 71 nights drop below freezing. The warmest reading in the 1991–2020 record is 41 °C, in July.

Rain is spread fairly evenly through the year, from 73 mm in February to 116 mm in September. There is no dry season to aim for.

Month by month

Month Avg high Rainfall Cloud
January 6.3 °C 79 mm 57 %
February 8.1 °C 73 mm 57 %
March 12.8 °C 100 mm 58 %
April 19.2 °C 87 mm 58 %
May 23.9 °C 100 mm 59 %
June 28.6 °C 91 mm 58 %
July 31.0 °C 110 mm 55 %
August 29.8 °C 98 mm 54 %
September 26.1 °C 116 mm 53 %
October 19.8 °C 89 mm 49 %
November 13.6 °C 78 mm 53 %
December 8.3 °C 91 mm 58 %

Temperature month by month

MonthAvg highAvg lowMeanRecord highRecord lowDays above 25 °CDays above 30 °CDays below 0 °C
January6.3 °C-1.9 °C1.6 °C22.8 °C-23.8 °C0021
February8.1 °C-1.3 °C2.7 °C26.0 °C-23.2 °C0018
March12.8 °C2.2 °C6.9 °C29.9 °C-18.5 °C1011
April19.2 °C7.9 °C13.0 °C33.5 °C-3.1 °C411
May23.9 °C13.4 °C18.3 °C35.8 °C0.7 °C1340
June28.6 °C18.5 °C23.3 °C40.3 °C8.1 °C25110
July31.0 °C21.3 °C25.9 °C41.2 °C13.9 °C30190
August29.8 °C20.5 °C24.9 °C38.3 °C12.5 °C29140
September26.1 °C17.1 °C21.2 °C35.7 °C6.8 °C1850
October19.8 °C10.7 °C14.8 °C34.7 °C0.1 °C400
November13.6 °C4.9 °C8.7 °C26.2 °C-5.5 °C004
December8.3 °C0.5 °C3.9 °C24.8 °C-14.4 °C0015

Rain, sun and wind month by month

MonthRainfallWet daysDaylightCloud coverHumidityWind
January79 mm99.7 h/day57 %67 %18 km/h
February73 mm911 h/day57 %66 %18 km/h
March100 mm1012 h/day58 %65 %18 km/h
April87 mm1013 h/day58 %65 %18 km/h
May100 mm1114 h/day59 %69 %16 km/h
June91 mm1215 h/day58 %69 %14 km/h
July110 mm1215 h/day55 %69 %13 km/h
August98 mm1114 h/day54 %71 %12 km/h
September116 mm912 h/day53 %72 %14 km/h
October89 mm811 h/day49 %72 %15 km/h
November78 mm810 h/day53 %70 %16 km/h
December91 mm99.5 h/day58 %71 %17 km/h

Where Washington ranks

RankingPositionValue
Places with the best weather in North America in May40thof 5087/100

Planning a trip? See the best time to visit Washington.

QuestionsCommon questions about Washington’s climate

When is the best time to visit Washington?

That depends on what you want, so the honest answer is a comparison rather than a single month. May, June, September sit closest to 20 °C on average, July is the warmest month and February the driest. The month-by-month table above has the full picture.

How hot does Washington get?

In July, the warmest month, daily highs average 31 °C. About 53 days a year pass 30 °C. The highest value in the 1991–2020 record is 41 °C.

How cold does it get in winter?

Nights average -1.9 °C in January, the coldest month. A normal year has 71 nights below freezing.

Which month is wettest in Washington?

September, averaging 116 mm over 9 days with rain. The driest month is February with 73 mm. The year as a whole averages 1,113 mm.

Are these figures a forecast?

No. They are 1991–2020 climate normals: the average of thirty years, which describes what a month is usually like in Washington rather than what any particular week will bring. Individual years can differ substantially from the normal.

Data sources and method

Normal period
1991–2020
Dataset version
era5-1991-2020-scores1.1
Last processed

Measured values come from ERA5 reanalysis and are reproduced unchanged. Calculated by us: monthly rankings, daylight hours, beach and comfort scores. Full formulas are on the methodology page.

Contains modified Copernicus Climate Change Service information 2026. Neither the European Commission nor ECMWF is responsible for any use that may be made of the Copernicus information or data it contains.