2007 CLIMATE SUMMARY

For the Blacksburg County Warning Area, 2007 will go down in the record books as one of the warmest and driest years. Average annual temperatures were the warmest on record at Roanoke (59.4F) and at Bluefield (56.9F). Danville (60.2F) and Blacksburg (54.3F) were also warm with their annual average temperature ranking 3rd and 4th respectfully. Lynchburg, who has the longest period of record of any station, since 1893, was warm with an annual average temperature of 57.1F. Despite being warm, this temperature was only the 41st warmest on record. Of the 12 months in 2007, nine of them had above average temperatures.

The warmest and coldest part of the year coincided with climatology, but it was the well above daily average temperatures in August that obliterated long-standing records for heat. August 2007 was the hottest August on record at 4 of the 5 climatic sites across Blacksburg's County Warning area. Among the 5 sites, no less than 62 daily records were set for both high maximum (32) and high minimum (30) temperatures combined. On two separate days (August 16th and 24th), Bluefield topped out at 95F which is the highest temperature for the month of August and second all-time for the entire year (96F set on July 16, 1988). Through the course of the year, 247 records were tied or broken at the 5 climatic sites across Blacksburg's County Warning area. Nearly half of the summer records that were tied or broken occurred at Bluefield. This is not a coincidence since Bluefield has the shortest period of record than any other climatic site (1959). Table 2 below, shows a cumulative total by month of temperature records for Roanoke, Lynchburg, Danville, Bluefield, and Blacksburg.

The warm temperatures were a direct result from the lack of rain the area did not receive. Despite several moderate rain events that prompted Flash Flood and Flood warnings for the area, rainfall was generally scattered through the year. These rain events (remnants of Tropical Storm Barry in June and Remnants of Hurricane Humberto in September to name a few) helped with the short term drought, but for most of the year, the area was placed in a moderate to extreme long-term drought (Table 5). Only one month (October) saw above normal precipitation in 2007 and at year’s end, annual precipitation deficits were a staggering 7-12 below normal. Roanoke (29.86”) and Danville (33.87”) were the 4th driest year on record. Bluefield (29.86”) and Blacksburg (29.86”) had a top ten driest year, 8th and 10th respectfully (Table 3). Again, Lynchburg (36.78”) had a higher ranking at 37 because of their period of record. As for snowfall amounts for 2007, all stations, but Bluefield, were below normal, with Roanoke having their 4th lowest snowfall ever (Table 4).

Table 5. U.S. Drought Summary December 25th, 2007

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The graphs below show the high and low temperature plotted for each station. The red plot indicates the normal high temperature, and the blue plot is normal low temperature. In the lower portion of the graph, the precipitation is plotted, with the observed in green, and the normal in olive green.

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