Narrative Summary - September 2009

September 2009 was warmer than normal, averaging 68.3ºF, 2.4º above normal (65.9ºF). The hottest
September (1990) averaged 72.4ºF, while the coolest (1985) averaged 58.8ºF. There were 8 days in
September with maximum temperatures >= 90ºF compared to a normal of 6. There were 59 days this year
with maximum temperatures >= 90ºF compared to a normal of 52 days. The greatest number was 79 days
in 1967. There were no days in September with maximum temperatures >= 100ºF compared to a normal of
<1, and a record of 3 on numerous occasions. There were 19 days this year with maximum temperatures
>= 100ºF compared to a normal of 12. The greatest was 28 days in 1958. The following temperatures
records were established during September 2009:

                       New         Old
Date  Category        Record      Record        Year
  16  High Minimum      65          65          1979 Tie

Precipitation for September 2009 totaled 0.06 inch, 18% of normal (0.33 inch). The wettest September
(1947) received 1.34 inches, while the driest (1991 and 1999) received no precipitation. Total
precipitation for 2009 (through September) is 3.42 inches, 78% of normal (4.40 inches).

The average wind speed for September 2009 was 8.4 miles per hour (mph), slightly above normal ( 7.9).
The windiest September (1961) averaged 9.2 mph, while the September with the lightest winds (1957)
averaged 5.4 mph. The peak gust for September 2009 was 46 mph on September 21. 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://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.