Delaware, PA climate
Delaware has chilly, snowy winters and pleasant summers, with plenty of rain. A typical July afternoon reaches 81°, a January night drops to 17°, and about 39 inches of snow falls in a normal winter.
NOAA 1991-2020 climate normals Updated once a decade5° warmer than normal today. The forecast high is 72°, and a typical Sep 30 in Delaware peaks around 67°.Live forecast: National Weather Service · Normal: NOAA 1991–2020
What a year in Delaware feels like
Winter
Spring
Summer
Fall
Delaware weather by month
Average highs, lows, rain and snow for every month, from NOAA’s 1991–2020 normals.
| Month | High | Low | Rain + melt | Snow | Wet days | Snow on ground | 30-yr range |
|---|---|---|---|---|---|---|---|
| January | 34° | 17° | 3.4" | 11.6" | 11 | 17 | 16° – 33° |
| February | 37° | 18° | 2.7" | 9.9" | 9 | 15 | 14° – 34° |
| March | 45° | 25° | 3.7" | 6.3" | 11 | 9 | 28° – 46° |
| April | 59° | 35° | 3.8" | 1.2" | 12 | 0 | 42° – 51° |
| May | 69° | 45° | 3.8" | 0 | 13 | 0 | 52° – 62° |
| June | 77° | 54° | 4.9" | 0 | 11 | 0 | 62° – 69° |
| July | 81° | 59° | 4.6" | 0 | 12 | 0 | 66° – 74° |
| August | 80° | 57° | 4.5" | 0 | 12 | 0 | 64° – 72° |
| September | 73° | 51° | 4.7" | 0 | 10 | 0 | 59° – 66° |
| October | 61° | 40° | 4.5" | 0.3" | 11 | 0 | 46° – 57° |
| November | 49° | 31° | 3.2" | 1.4" | 9 | 1 | 35° – 45° |
| December | 38° | 23° | 4.0" | 8.0" | 11 | 10 | 23° – 41° |
| Year | 59° | 38° | 47.6" | 38.7" | 132 | 52 |
“Wet days” have at least 0.01" of rain or melted snow. “Snow on ground” counts days with 1" or more. The 30-year range is the coldest and warmest that month’s average temperature got between 1991 and 2020.
Rain and snow in Delaware
Delaware gets 48 inches of rain and melted snow a year. June is the wettest month and February the driest. Rain or snow falls on about 132 days a year. Snow covers the ground about 52 days of the year.
About 163 frost-free days a year
In half of years the last 32° night comes by April 30 and the first one by October 11. That leaves about 163 frost-free days for gardens, shorter than 68% of U.S. towns.
Heating and cooling a home in Delaware
Engineers use “degree days” to estimate how hard a furnace or air conditioner works. In Delaware, 91% of that work is heating and 9% is cooling, so the furnace matters far more than the air conditioner.
Degree days measure how far each day’s average temperature falls below or rises above 65°, added up over a year. Source: NOAA station normals.
Delaware and its neighbors
Delaware borders 5 towns with climate data. January nights across them vary by 1.3°. Dingman has the coldest January nights (16°) and Sandyston the hottest July afternoons (84°). Delaware’s January low is 17° and its July high 81°.
Temperatures and rain come from NOAA’s 5 km grid, so each town gets its own value.
How Delaware compares
Compared with every U.S. town and city on TownTapestry, each counted once.
Warmer than it used to be
The last 30 years in Delaware averaged 1.8° warmer than the 1900s. The biggest change is in December (+3.5°). The shift is larger than in 89% of U.S. towns.
Change by month1991–2020 average minus 1901–2000 average, at Delaware’s spot on NOAA’s grid
How much a month can swing
A normal is an average, and real years wander around it. February swings the most: between 1991 and 2020 its average temperature ranged from 14° to 34°. September is the most reliable, staying within 7°.
Common questions about Delaware’s climate
What is the coldest month in Delaware?
January, with a typical high of 34° and a low of 17°.
What is the hottest month in Delaware?
July, with a typical high of 81° and a low of 59°. About 13 days a year reach 90°.
How much snow does Delaware get?
About 39 inches in a normal winter, most of it in January.
When is the first frost in Delaware?
In half of years the first 32° night comes by October 11, and the last spring frost by April 30.
What is the rainiest month in Delaware?
June, with 4.9 inches of rain and melted snow. The year totals 48 inches.
Temperatures and rainfall come from NOAA’s gridded climate normals for Delaware itself (about a 3-mile square). Snow, frost dates and day counts come from NOAA’s weather station at Sussex 3 Wnw, NJ (14 mi) away. Normals are 30-year averages, not a forecast. Source: NOAA NCEI U.S. Climate Normals, 1991–2020 and 1901–2000.