Tri-City residents can look forward to another month that may be wetter than usual, after a rainy October.
The month just ended was the second-rainiest on record in Kennewick with 2.53 inches of rain, according to the National Weather Service. The only October wetter since data started being recorded in the late 1800s was in 1947.
At the Pasco airport, precipitation set a record for the month of October at 2.58 inches. However, records there go back only a few decades.
The rainfall may be due to early indications of a La Niña developing, said Dennis Hull of the National Weather Service.
A 70 percent chance of La Niña, which would bring more precipitation than usual to the Mid-Columbia, is forecast for the winter of 2016-17, and a 55 percent chance of it persisting through the winter is predicted by the National Oceanic and Atmospheric Administration.
The amount of rain that fell (in October) is significant, but so too, is the fact that it’s only October. The wettest months in the Pacific Northwest tend to be during winter.
Nic Loyd, WSU AgWeatherNet
“The amount of rain that fell this month is significant, but so too, is the fact that it’s only October,” said meteorologist Nic Loyd, of Washington State University’s AgWeatherNet in Prosser.
October is a good month for a heavy rain, he said. In winter or spring flooding would have been more likely, but the wet October followed a typically dry summer so the soil moisture and river levels were low, he said.
The wettest months of the year usually are during the winter in the Northwest, Loyd said.
In the Tri-Cities the heaviest rainfall was recorded on Oct. 30, with 0.88 inch measured at the Tri-Cities airport, according to the weather service.
At Hanford the heaviest rainfall was the 1.14 inches recorded in a 24 hour period extending to just after midnight Oct. 10, according to the Hanford Meteorology Service.
It was the second rainiest 24-hour period on record for October and the eighth highest rainfall total for any day of the year based on records dating back to about 1945.
Tri-City residents who did not enjoy the rain can be glad they do not live in Spokane.
The city received 6.23 inches of rain, the most not just for an October, but any month since rainfall began being recorded in 1881, Loyd said.
45 mph peak Pasco wind gust Oct. 14
41 mph peak Kennewick wind gust Oct. 14
37 mph peak Richland wind gust Oct. 7
Normal precipitation for the Tri-Cities in November is just over 1 inch.
The Tri-Cities also may have warmer than usual temperatures this month, according to the weather service.
Normal Tri-City temperatures fall from about 58 at the start of November to about 43 at the end of the month. Normal lows fall from about 37 to about 30.
Temperatures in the Tri-Cities in October were warmer than usual.
Lows that averaged 6.6 degrees above normal, as recorded at the Tri-Cities Airport, were mainly responsible, Hull said. Cloudy weather preserved some of the daytime heat at night for average lows of 44.5 degrees at the Tri-Cities airport.
Highs were just 2.3 degrees above normal at 54.2 degrees, as recorded in Pasco.
The coldest day of the month was Oct. 12, with a low of 29 at the Pasco airport. No other day had temperatures below freezing in the Tri-Cities.
Precipitation for the year has reached 8.2 inches, as recorded at the Tri-Cities airport. The total is 1.67 inches above normal.
The peak wind gust in the Tri-Cities in October was 45 mph, which was recorded at the Tri-Cities airport on Oct. 14. At the Hanford meteorological station it was 50 mph on the same day.