September Temperatures
Preliminary data indicates that the statewide average temperature in September was 70.2°F, which was 2.2°F above the 1981-2010 normal of 68.0°F (Figure 1). September 2017 was the 19th warmest September since 1895.
September Precipitation
Delaware’s statewide precipitation for September 2017 averaged 2.17 inches, 1.43 inches below the 1981-2010 mean (Figure 2), placing it in the driest one-third of Septembers since records began in 1895.
Statewide Spatial Averages
Data from the Delaware Environmental Observing System (DEOS) show that temperatures were above normal across the majority of the State with the largest positive temperature departures found across Chester County, PA and northern New Castle County, DE. (Figure 3). All stations in the DEOS network recorded below normal precipitation except for extreme southeastern Delaware (Figure 4). In the northern portions of the region, negative precipitation departures reached over 3 inches at several stations.
-
- Figure 1. Delaware statewide mean September temperature (°F) 1895-2017. Red line indicates 1981-2010 normal.
-
- Figure 2. Delaware statewide September precipitation (inches) 1895-2017. Red line indicates 1981-2010 normal.
-
- Figure 3. September 2017 average temperature departures (°F) from the 1981-2010 mean based upon DEOS station data.
-
- Figure 4. September 2017 precipitation departures (inches) from the 1981-2010 mean based upon DEOS station data.
Similar Posts
- September 2023 – Warm with Above Normal Precipitation Across Delaware (2023)
- September 2022 – Near Normal Temperatures and Dry Conditions Across Delaware (2022)
- September 2021 – Warm with Near Normal Precipitation Across Delaware (2021)
- September 2020 – Near Normal Temperature and Precipitation Across Delaware (2020)
Partners
