Narrative Summary - August 1999
August 1999 was slightly warmer than normal, averaging 76.2ºF, 1.1º above normal (75.1ºF).
The warmest August occurred in 1967 and averaged 81.5ºF, while the coolest was 69.8ºF in
1964. Through August there have been 45 days with maximum temperatures >= 90ºF compared to a
normal of 47 days, and 7 days with maximum temperatures >= 100ºF compared to a normal of 13
days. The following daily temperature records were established in August:
New Old
Date Category Record Record Year
3 High Minimum 75 75 1994 Tie
30 Low Maximum 64* 68 1951
31 Low Minimum 43 45 1965
31 Low Maximum 72 72 1971 Tie
*The maximum temperature of 64ºF on August 30 was an all-time record low maximum for the Precipitation for August 1999 totaled 0.57 in., 211% of normal (0.27 in.). Most of the
precipitation (0.48 in.) was received during a thunderstorm on August 5, with 0.40 in. falling in a
35-minute period. The wettest August, in 1977, received 1.36 in., while the driest, in 1988,
received no precipitation. Total precipitation since January 1 was 2.94 in., 81% of normal (3.63
in.).
The average wind speed for August 1999 was 8.2 miles per hour (mph), 0.3 mph above normal
(7.9 mph). The windiest August on record averaged 9.5 mph (1996), while the August with the
lightest winds (1956) averaged 6.0 mph. The peak gust for the month was 44 mph on August 29.
The record wind gust for August was 66 mph in 1961.
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/
The summer of 1999 (June, July and August) was cooler than normal, averaging 72.5ºF, 1.2º
below normal (73.7ºF). The hottest summer, in 1958, averaged 78.2ºF, while the coolest, in
1980, averaged 70.2ºF. The highest temperature was 105ºF on July 28. Precipitation for the
summer season totaled 0.95 in., 115% of normal (0.83 in.). The wettest summer, in 1950,
received 2.99 in., while the driest, in 1973, received only 0.03 in.
For additional information contact:
| Ken Burk | 373-3215 | |
| Dana Hoitink | 372-6414 |
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.