Narrative Summary - April 2009

April 2009 was slightly cooler than normal, averaging 51.7ºF, 1.8º below normal (53.5ºF). The warmest
April (1994) averaged 58.2ºF, while the coldest (1955) averaged 47.5ºF. The following daily
temperature records were established:

       			New	Old
Date	Category       	Record	Record	Year
  1	Low Maximum	  44	  45	1976
 19	High Maximum  	  80	  78	1956
 20	High Maximum	  84	  84	1956 Tied
 21	High Maximum	  87	  85	1956
 28	Low Maximum	  50	  54	1995

Precipitation for April 2009 totaled 0.39 inches, 89% of normal (0.44 inch). The wettest April (2003)
received 2.23 inches, while the driest (1999 and earlier years) received only a trace. Total precipitation
for 2009 (through April) is 2.98 inches, 116% of normal (2.57 inches).

The average wind speed for April 2009 was 8.8 miles per hour (mph), which was normal (8.8 mph). The
windiest April (1959 and 1972) averaged 11.1 mph, while the April with the lightest winds (2004)
averaged 7.2 mph. The peak gust for April 2009 was 36 mph on April 23. The record wind gust for April
was 73 mph in 1972.

Special note: This is the second year in a row that there are visible patches of snow across the
Rattlesnake ridge into the month of May. A rare occurance.

The monthly climatological data summaries, as well as other information, are available on the Internet.
Address: http://hms.pnl.gov/

For additional information contact:
Ken Burk373-3215
HMS Staff373-2716

Note: The information in this summary pertains specifically to
the Hanford Meteorology Station (HMS), which is located
approximately 25 miles northwest of Richland, Washington. No
attempt should be made to infer meteorological conditions at other
locations from these data.