Wilmington, DE weather in August
Expect warm, often humid weather with some rain in Wilmington in August, with highs near 85°F and lows near 67°F. Rain falls on about 9 days. It is one of the warmest months in Wilmington.
- Normal high
- 85°F
- Normal low
- 67°F
- Wet days
- 9
- 4.0 in total
- Muggy days
- 16
- dew point 65°F+
How August changes from start to finish
| August 1 | August 31 | |
|---|---|---|
| Normal high | 86°F | 83°F |
| Normal low | 68°F | 64°F |
| Chance of a wet day | 31% | 27% |
| Sunrise / sunset | 6:01 am / 8:15 pm | 6:29 am / 7:35 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 am70°Fdew point 64°F
- 9 am77°Fdew point 65°F
- Noon82°Fdew point 63°F
- 3 pm84°Fdew point 62°F
- 6 pm81°Fdew point 63°F
- 9 pm76°Fdew point 65°F
NOAA hourly normals (local standard time) from Philadelphia Intl Airport (19 mi away); average wind 8 mph; clear or few clouds in 65% of daytime hours, mostly cloudy or overcast in 26%.
What kind of days to expect
- Comfortable dayshigh 65-80°F and dew point under 60°F3 of 31
- Beach dayshigh 80-95°F, under 0.05 in of rain, afternoon wind under 15 mph19 of 31
- Hot dayshigh 90°F or more6 of 31
- Muggy daysdaily mean dew point 65°F or more16 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 4.0 in; a dry August brings about 2.5 in and a wet one about 5.1 in (25th and 75th percentiles). About 3 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 89°F
- Coolest August2000: average high 81°F
- Wettest August2011: 14.7 in
- Driest August2008: 1.2 in
- Highest reading99°F (August 9, 2001)
- Lowest reading51°F (August 22, 2000)
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 | 87°F | 85°F | 79°F |
| Normal low | 68°F | 67°F | 59°F |
| Wet days | 10 | 9 | 9 |
| Comfortable days | 2 | 3 | 13 |
| Daylight | 14.7 h | 13.7 h | 12.4 h |
Highs change by -2°F from July and -6°F into September.
Nearby alternatives in August
- Cooler: Montauk, NY209 mi · high 80°F · 9 wet days
How Wilmington ranks in August
- Normal high211th warmest of 378 cities; 2nd of 2 in Delaware
- Wet days187th driest of 378
- Comfortable days157th most of 341
What to pack for Wilmington in August
- Light, breathable clothing – highs near 85°F and about 16 muggy days
- A rain jacket or umbrella – rain on about 9 days
- A swimsuit – about 19 beach days
Heating and cooling
August has 1 heating degree days and 334 cooling degree days (base 65°F), 6% of the year's total heating and cooling demand.
Questions
How hot is Wilmington in August?
The normal high is 85°F and the normal low is 67°F. From 1991 to 2020 the hottest August reading was 99°F (August 9, 2001).
Does it rain a lot in Wilmington in August?
About 9 days in August have at least 0.01 in of precipitation, and the normal total is 4.0 in. The wettest August in 1991-2020 was in 2011 (14.7 in); the driest was in 2008 (1.2 in).
Is August a good time to visit Wilmington?
August ranks 6th of 12 months on our comfort score for Wilmington (52 out of 100). It has about 3 comfortable days and about 6 days at 90°F or hotter. The best month is May.
Where the numbers come from
- Temperature, rain, snowfall and snow depth: Wilmington New Castle Co Airport (USW00013781), 5.8 mi SSW of the city center, 79 ft . NOAA normals and daily records, 1991-2020.
- Frost dates: Wilmington Porter Rsch (USC00079605), 1.9 mi N of the city center, 270 ft (179 ft higher than the city). NOAA normals and daily records, 1991-2020.
- Humidity and wind by hour: Philadelphia Intl Airport (USW00013739), 19 mi ENE of the city center, 10 ft (81 ft lower than the city). NOAA normals and daily records, 1991-2020.
- Cloud cover: Millville Muni Airport (USW00013735), 37 mi SE of the city center, 70 ft . NOAA normals and daily records, 1991-2020.
- Daily humidity and wind: Philadelphia International Airport (724080-13739), 19 mi ENE of the city center, 7 ft (84 ft lower than the city). Hourly observations, 1991-2020.