Climate averages 1991–2020
New Haven weather
in August.
A warm, wet month: the 2nd warmest and the 5th driest of the year.
Long-term climate patterns, not a forecast for a particular trip.
August is a warm month in New Haven: daytime highs average 26.3°C and nights cool to about 19.6°C. By daytime temperature it is the 2nd warmest of the 12 months.
Expect about 102 mm of rain on roughly 10 days, which makes August a wet month (the 5th driest of the 12 months). Daylight, from sunrise to sunset, lasts about 13 h 50 min on an average August day.
The nearest other city in this atlas is Bridgeport (26 km away). In August its highs average 26.7°C, about as warm as New Haven, with 103 mm of rain.
Among the 498 cities listed in the United States, New Haven ranks joint 423rd of 498 for the warmest August highs and joint 411th of 498 for the driest August (rainfall, lowest first). The mean August high of those 498 cities is 29.9°C; New Haven is 3.6°C cooler than that mean.
From August to September, average highs fall by 3.7°C to 22.6°C, and monthly rainfall rises from 102 mm to 109 mm.
The annual picture
August 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
New Haven climate table
| Month | Average highHigh / low | Average low | Rainfall mm/month | Rain days ≥1 mm/day | Daylight hours/dayDaylight h/day |
|---|---|---|---|---|---|
| January | 2.7°C-3.6°C | -3.6°C | 108 | 10.1 | 9.610 h |
| February | 3.6°C-3.3°C | -3.3°C | 97 | 9.2 | 10.611 h |
| March | 7.3°C0.0°C | 0.0°C | 128 | 10.9 | 11.912 h |
| April | 13.1°C5.2°C | 5.2°C | 116 | 11.5 | 13.313 h |
| May | 18.4°C10.6°C | 10.6°C | 98 | 11.6 | 14.514 h |
| June | 23.6°C16.2°C | 16.2°C | 98 | 10.5 | 15.115 h |
| July | 27.0°C19.9°C | 19.9°C | 82 | 9.5 | 14.815 h |
| August, selected | 26.3°C19.6°C | 19.6°C | 102 | 9.6 | 13.814 h |
| September | 22.6°C16.2°C | 16.2°C | 109 | 8.9 | 12.513 h |
| October | 16.5°C10.5°C | 10.5°C | 129 | 10.1 | 11.111 h |
| November | 10.7°C4.9°C | 4.9°C | 110 | 9.5 | 9.910 h |
| December | 5.6°C0.0°C | 0.0°C | 137 | 11.2 | 9.39 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
August in nearby cities
- Bridgeport in AugustUnited States · 26 kmHigh 26.7°C · Low 19.7°C · 103 mm rain
- Waterbury in AugustUnited States · 30 kmHigh 27.2°C · Low 18.3°C · 104 mm rain
- New Britain in AugustUnited States · 41 kmHigh 27.5°C · Low 17.9°C · 100 mm rain
- Danbury in AugustUnited States · 45 kmHigh 27.1°C · Low 18.3°C · 115 mm rain
- Norwalk in AugustUnited States · 45 kmHigh 27.0°C · Low 19.9°C · 103 mm rain
- Hartford in AugustUnited States · 55 kmHigh 27.6°C · Low 17.8°C · 100 mm rain
- Stamford in AugustUnited States · 58 kmHigh 27.2°C · Low 19.9°C · 103 mm rain
- Greenburgh in AugustUnited States · 82 kmHigh 27.3°C · Low 19.5°C · 100 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 New Haven) is explained once on the New Haven year overview and on the Sources, method and limits page.