Delaware Water Gap National Recreation AreaPage 21 of 31
Delaware Water Gap in 2021: 7th warmest year and 26th wettest since 1895
At Delaware Water Gap National Recreation Area, 2021 ranked as the 7th warmest and 26th wettest year in the record that begins in 1895. The annual average temperature was 50.5 °F, 2.8 °F above the long-term average, and 52.56 inches of precipitation fell, almost 6 inches above it. September was the wettest month relative to normal, and December the warmest.
The figures come from a National Park Service summary by the Eastern Rivers and Mountains Network, which measures ecosystem "vital signs," including weather and climate, in selected parks in West Virginia, Pennsylvania, New Jersey and New York. The numbers are county-scale averages for Monroe, Northampton and Pike counties in Pennsylvania and Sussex and Warren counties in New Jersey, courtesy of NOAA's Climate at a Glance program.
Weather and climate
Weather is the short-term change in the atmosphere, from minutes to months. Climate is what to expect from long-term patterns of 30 years or more: climate is a hot summer, weather is a warm rainy day. Departures below are measured against averages for 1895 to 2020.
Temperature, month by month
Eleven months were warmer than the long-term average; only May was cooler.
| Month | Average temperature (°F) | Departure from long-term average (°F) |
|---|---|---|
| January | 28.3 | +3.8 |
| February | 26.6 | +0.8 |
| March | 39.2 | +4.3 |
| April | 48.7 | +2.3 |
| May | 56.7 | -0.4 |
| June | 67.2 | +1.7 |
| July | 70.9 | +0.7 |
| August | 71.6 | +3.5 |
| September | 64.0 | +2.8 |
| October | 56.6 | +6.4 |
| November | 39.3 | +0.1 |
| December | 36.4 | +7.8 |
| Year | 50.5 | +2.8 |
Precipitation, month by month
| Month | Total precipitation (in.) | Departure from long-term average (in.) |
|---|---|---|
| January | 1.71 | -1.59 |
| February | 4.04 | +1.05 |
| March | 3.27 | -0.40 |
| April | 1.68 | -2.22 |
| May | 4.71 | +0.65 |
| June | 2.96 | -1.33 |
| July | 6.56 | +1.90 |
| August | 8.31 | +3.84 |
| September | 9.73 | +5.58 |
| October | 6.27 | +2.47 |
| November | 1.81 | -1.80 |
| December | 1.50 | -2.21 |
| Year | 52.56 | +5.94 |
The long trend
For the counties around the park, annual average temperature has risen by approximately 0.27 °F per decade and annual total precipitation by approximately 0.39 inches per decade since 1895.
Annual average temperature and annual total precipitation, 1895 to 2021. Dashed lines are linear estimates of change. Chart from the National Park Service's page.
National Park Service scientists have also forecast change. Models estimate that by 2100 the park's annual average temperature will rise by 3.2 to 9.4 °F, from the best-case to the worst-case scenario, and that annual total precipitation will rise by 8 to 15 percent.
Climate change in the parks
The summary says rapid climate change challenges national parks in new ways: wildlife migrations are altered, more destructive storms threaten cultural resources and park facilities, and habitat is disrupted. It points readers to the National Park Service's climate change site.
Sources
- National Park Service, Eastern Rivers and Mountains Network, "2021 Weather In Review: Delaware Water Gap National Recreation Area": https://www.nps.gov/articles/000/2021-weather-in-review-delaware-water-gap-national-recreation-area.htm. The page's lead photograph, which shows visitors and staff, and its seasonal-ranking graphics are left out.
- National Park Service; rewritten in hubnx's own words.