Narrative Summary - September 2004

The average temperature for September 2004 was cooler than normal, averaging 64.9ºF, 1.0º below normal
(65.9ºF). The warmest September occurred in 1990 and averaged 72.4ºF, while the coolest, in 1985, averaged
58.8ºF. There were no days during the month with maximum temperatures >= 90ºF, compared to a September
normal of 6 such days. This was only the 6th September on record without a 90º day. The 2004 calendar year
total was 58 days >= 90ºF, compared to a yearly normal of 52 days. The greatest number of days with maximum
temperatures >= 90ºF was 79 days in 1967, and the least 29 days in 1980. There were 22 days with maximum
temperatures >= 100ºF which was the 7th highest total on record (the most was 28 days in 1958, the least was 1
day in 1954). The following temperature records were established in September. 

                           New          Old
Date      Category        Record       Record       Year
 27	High Minimum	    60		 60	    2003 Tie

Precipitation for September 2004 totaled 0.14 inch, 42% of normal (0.33 inch). The wettest September, in
1947, received 1.34 inches; and the driest, in 1999 and earlier years, received no precipitation. Total
precipitation for 2004 (through September) is 6.44 inches, 146% of normal (4.40 inches).

The average wind speed for September 2004 was 7.7 miles per hour (mph), 0.4 mph above normal (7.3 mph).
The windiest September on record (1961) averaged 9.2 mph, while the September with the lightest winds
(1957) averaged 5.4 mph. The peak gust for the month was 42 mph on September 4 and 18. The record wind
gust for September was 65 mph in 1953.

The monthly climatological data summaries, as well as other information, are available
on the Internet. Address: http://terrassa.pnl.gov:2080/HMS/. Hanford Site personnel can
access the HMS Intranet site at: http://hms.rl.gov/

For additional information contact:
Ken Burk373-3215
Dana Hoitink372-6414

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.