Washington, DC weather in August
In August, Washington sees highs around 88°F and lows around 71°F: hot and humid, with some rain. Rain falls on about 9 days. It is one of the warmest months in Washington.
- Normal high
- 88°F
- Normal low
- 71°F
- Wet days
- 9
- 3.3 in total
- Muggy days
- 19
- dew point 65°F+
How August changes from start to finish
| August 1 | August 31 | |
|---|---|---|
| Normal high | 89°F | 86°F |
| Normal low | 72°F | 69°F |
| Chance of a wet day | 31% | 27% |
| Sunrise / sunset | 6:09 am / 8:19 pm | 6:36 am / 7:40 pm |
| Daylight | 14.2 h | 13.1 h |
Chance of a wet day: average for the first and last 7 days of the month. Times are local clock time (Eastern Time).
A typical August day
- 6 am72°Fdew point 66°F
- 9 am78°Fdew point 66°F
- Noon84°Fdew point 65°F
- 3 pm85°Fdew point 65°F
- 6 pm82°Fdew point 65°F
- 9 pm77°Fdew point 66°F
NOAA hourly normals (local standard time) from Washington Reagan Airport (3 mi away); average wind 8 mph; clear or few clouds in 45% of daytime hours, mostly cloudy or overcast in 37%.
What kind of days to expect
- Comfortable dayshigh 65-80°F and dew point under 60°F1 of 31
- Hot dayshigh 90°F or more11 of 31
- Muggy daysdaily mean dew point 65°F or more19 of 31
- Wet daysat least 0.01 in of rain or melted snow9 of 31
- Notable rainat least 0.10 in6 of 31
- Freezing nightslow 32°F or below0 of 31
- Snow on the groundsnow depth 1 in or more0 of 31
Average days per August, counted from daily records for each year 1991-2020.
Rain in August
Normal precipitation is 3.3 in; a dry August brings about 2.0 in and a wet one about 4.2 in (25th and 75th percentiles). About 2 days bring half an inch or more, and about 1 an inch or more.
How August varies from year to year
- Warmest August, 1991-20202016: average high 92°F
- Coolest August1992: average high 82°F
- Wettest August2011: 8.9 in
- Driest August1998: 0.6 in
- Highest reading105°F (August 17, 1997)
- Lowest reading56°F (August 6, 1994)
From the station's daily records with NOAA quality flags removed; most recent date shown when a reading repeats.
August compared with July and September
| July | August | September | |
|---|---|---|---|
| Normal high | 90°F | 88°F | 81°F |
| Normal low | 72°F | 71°F | 64°F |
| Wet days | 11 | 9 | 9 |
| Comfortable days | 1 | 1 | 10 |
| Daylight | 14.6 h | 13.6 h | 12.4 h |
Highs change by -2°F from July and -7°F into September.
Nearby alternatives in August
- Cooler: Frederick, MD41 mi · high 83°F · 10 wet days
How Washington ranks in August
- Normal high170th warmest of 378 cities
- Wet days179th driest of 378
- Comfortable days196th most of 341
What to pack for Washington in August
- Light, breathable clothing – highs near 88°F and about 19 muggy days
- A rain jacket or umbrella – rain on about 9 days
Heating and cooling
August has 0 heating degree days and 446 cooling degree days (base 65°F), 8% of the year's total heating and cooling demand.
Questions
How hot is Washington in August?
The normal high is 88°F and the normal low is 71°F. From 1991 to 2020 the hottest August reading was 105°F (August 17, 1997).
Does it rain a lot in Washington in August?
About 9 days in August have at least 0.01 in of precipitation, and the normal total is 3.3 in. The wettest August in 1991-2020 was in 2011 (8.9 in); the driest was in 1998 (0.6 in).
Is August a good time to visit Washington?
August ranks 8th of 12 months on our comfort score for Washington (46 out of 100). It has about 1 comfortable day and about 11 days at 90°F or hotter. The best months are April, May and October.
Where the numbers come from
- Temperature, rain, snowfall, snow depth, frost dates and humidity and wind by hour: Washington Reagan Airport (USW00013743), 3.2 mi S of the city center, 10 ft . NOAA normals and daily records, 1991-2020.
- Cloud cover: Camp Springs Andrews AFB (USW00013705), 11 mi ESE of the city center, 282 ft (258 ft higher than the city). NOAA normals and daily records, 1991-2020.
- Daily humidity and wind: Ronald Reagan Washington Natl Airport (724050-13743), 3.3 mi S of the city center, 13 ft . Hourly observations, 1991-2020.