Narrative Summary - September 1998

September 1998 was much warmer than normal, averaging 71.0ºF, 5.3º above normal (65.7ºF),
and the fourth warmest on record. The warmest September occurred in 1990 and averaged 72.4ºF.
The coolest September was 58.8ºF in 1985. September 1998 was the 14th consecutive month
that averaged above normal. There were 12 days in September with maximum temperatures >= 90ºF
(normal for September is 5 days), and there were 3 days with maximum temperatures >= 100ºF
(normal is 0). For the year there were 73 days (the third highest on record) with maximum
temperatures >= 90ºF (normal is 52 days). The most 90º days were 79 in 1967 and the least were
29 days in 1980. There were 26 days (also the third highest on record) in 1998 with maximum
temperatures >= 100ºF (normal is 13 days). The most 100º days were 28 in 1958 and the least
was one day in 1954. The following daily temperature records were established in September:

			New	  Old
Date   Category       Record    Record     Year
  2   High Maximum     102       102       1950   Tie
  3   High Maximum     102       101       1988
 14   High Maximum      94        94       1955   Tie

Precipitation for September 1998 totaled only 0.10 inch, 32% of normal (0.31 inch). The wettest
September, in 1947, received 1.34 inches, while the driest, in 1991, recorded no precipitation.
Precipitation since January 1, 1998 totals 4.44 inches, 113% of normal (3.94 inches).

September 1998's average wind speed was 6.7 miles per hour (mph), compared to a September
normal of 7.4 mph. The peak wind gust for the month was 35 mph recorded on September 17.
The record wind gust for September was 65 mph in 1953. The windiest September averaged 9.2
mph (1961); while the September with the lightest winds (1957) averaged 5.4 mph.

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