Eisenhower National Historic Site and Gettysburg National Military Park: Weather of 2008

Knight, Paul; Wisniewski, Tiffany; Bahrmann, Chad; Miller, Sonya

The purpose of this report is to provide a concise climate summary for 2008 at Eisenhower NHS and Gettysburg NMP, as part of the Mid-Atlantic Network's Weather and Climate Monitoring Program. Specifically it contains summaries for weather, temperature, and precipitation and descriptions of observing stations, stream flow, and draught status. With a high temperature of 70°F (21.1°C) on January 8, the first month of 2008 was warmer than normal. The rest of the winter had a similar temperature trend and finished as the 33rd warmest since records started in 1895 (a ranking of 57 is normal). The spring featured varying temperature trends, with April being above average and May well-below average. Despite the lower temperatures in the beginning of May, the last frost occurred around the usual date. Readings in June rebounded and the month averaged above the long-term normal by 2°F (1.1°C). The second half of the year was slightly cooler than normal, but ended with a slightly above normal month in December. This was aided by temperatures reaching from 61°F–69°F (16.1–20.6°C) on December 28 and 29. The highest temperature of the year occurred July 20–21 with a reading of 95°F (35°C). The lowest temperature of the year, 1°F (-17.2°C), was recorded on February 21. Precipitation in the winter months was above normal and ranked the 36th wettest since 1895. The second quarter of 2008 was close to normal for precipitation. Rainfall for the second half of the year averaged above normal, with the summer ranking as the 13th wettest. Overall, the year was wetter than 2007 and ranked 27th wettest since 1895 with total precipitationof 49.3 in (1,253 mm). The average temperature in 2008 was 52.0°F (11.1°C), which was exactly average. The number of days with a minimum temperature less than 32°F (0°C) was well-above average at 134, versus the 101.7 day average (Table 1). The average temperatures allowed the growing season to be near normal. As far as precipitation, the year was almost 10 in (254 mm) above the average of 41.0 in (1,054 mm). Dry spells of more than a week occurred most frequently in the late summer and early fall. At one point in October, the region had 15 consecutive days without rainfall. It is interesting to note that snowfall was well-below average. A large outbreak of severe weather occurred June 10, which brought hail up to 1 in (25 mm) in diameter to Gettysburg. On September 7, which was one of the wettest days of the year, Tropical Storm Hannah dropped 2.2in (57 mm) of rain on the area. Soil temperatures continued to rise in response to the long-term warming trend, and the amount of incoming energy from the sun rose despite being in a sola rminimum since 2007.

Eisenhower National Historic Site and Gettysburg National Military Park: Weather of 2008

Series