January 2024 – Warm and Wet Across Delaware

January Temperatures

Preliminary data indicates that the statewide average temperature in January was 37.6^o F, which is 2.4^o F above the 1991-2020 mean value of 35.2^o F (Figure 1).  January’s temperature fell within the top one-third of readings over the last 130 years.   

January Precipitation

Delaware’s statewide precipitation for January 2024 averaged 6.12 inches, 2.77 inches above the 1991-2020 mean of 3.35 inches (Figure 2).  This month’s precipitation was the 8^th highest for January since records began in 1895.

Statewide Spatial Anomalies

Data from the Delaware Environmental Observing System (DEOS) show that temperature departures were uniformly positive across the entire state (Figure 3) with some locations seeing positive anomalies of more than 3^o F. 

Precipitation anomalies were positive across the entire state, with Sussex County recording some departures of more than four inches (Figure 4).

Delaware experienced two significant snowfall events during January.  On January 15^th, snow fell across the entire state, with up to three inches observed across northern New Castle County.  A more significant snowfall occurred just a few days later, on January 19^th.  Snow totals of over 5 inches were found across areas of New Castle and Kent counties, and the entire state was blanketed with snow.

National Anomalies

Temperatures were above normal across the Northeast United States and the Great Lakes Region (Figure 5), with anomalies reaching over 7^o F across parts of Minnesota and Wisconsin.  Much of the central portion of the country, and the Pacific Northwest saw below normal temperatures during the month.  Precipitation departures were positive across the eastern one-third of the country (Figure 6) and along the northern Pacific coast. The remainder of the country had near normal amounts of precipitation. The 500 hPa height pattern for January matched the temperature departures very well with an anomalous jet stream trough located over the northwest and central United States, while ridging was found over the Northeast and Great Lakes (Figure 7).

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