Precipitation remained on the missing list last month as summer sauntered off the stage and fall arrived.
September finished with only trace amounts of rainfall, with the last 27 days of the month coming up dry. This left total rain and snowfall this year at 9.59 inches, which is 4.24 inches below average.
The “water year” precipitation, which runs from October of last year through September and accounts for spring runoff, finished at 16.83 inches, which is 4.02 inches below normal.
According to the U.S. Department of Agriculture, Walla Walla and Columbia counties, along with the rest of Eastern Washington, remained parched. Most crops were harvested, other than potatoes and corn. Fall seeding started, even with very low moisture in the area.
Cooler days and nights began arriving even before the start of autumn on Sept. 22. The warmest day of the month, 93 degrees, was on Sept. 7, and the coolest night was on Sept. 25, when the mercury dropped to 45 degrees. The average high for the month was 76.7 degrees, which was 1.2 degrees below normal, and the average low was 52 degrees, which was 0.6 degrees below average.
The highest wind gust was 38 mph, which occurred on Sept. 27.
According to the National Weather Service, Walla Walla may see its first fall freeze this month, as weather records show Oct. 28 is the average date for temperatures to drop below 32 degrees in Walla Walla. The earliest freeze occurred on Sept. 17, 1965, and the latest came on Dec. 31, 1968.
Frost or no frost, the trend of cooler days and nights will continue, with normal highs for Walla Walla falling from 71 degrees at the start of October to 56 degrees by Halloween. Nighttime lows fall from 48 degrees to 39 degrees.
The outlook for October from the federal Climate Prediction Center calls for near-normal temperatures and below-normal precipitation, which is 1.68 inches based on a 30-year average.