AgWeatherNet Weekly Weather Outlook Monday Update for March 22 to March 28, 2021

Unsettled weather giving way to drying conditions toward the weekend

Mark Ingalls, AgWeatherNet Intern

Synopsis:

Shower activity is expected to taper off statewide with rain and mountain snow coming to an end for most locations overnight Monday night. Tuesday is expected to be mostly dry but a disturbance similar to Monday's should start spreading precipitation starting on the Olympic Peninsula by Wednesday morning reaching east of the Cascades by the afternoon hours. Snow levels are expected to be around 3,000 feet for a few inches of snow on mountain passes into Thursday. A few showers may linger in parts of the state into early Friday morning, otherwise a building ridge of high pressure should provide mostly sunny skies and warmer temperatures through Saturday before the next system begins potentially impacting Western Washington as early as Sunday afternoon.

Discussion:

Rain and mountain snow showers along and behind a frontal boundary crossing Washington are expected to taper off overnight with perhaps a few lingering showers lasting along the coast into Tuesday. Otherwise, a mostly dry day is expected before a shortwave trough slides south into the state from British Columbia to bring another round of rain and mountain snow for just about everyone except the Columbia Basin and Yakima Valley. Snow levels look to be around 3,000 feet. This is slightly higher than what was observed Monday but is low enough that a few inches of snow are possible on all the major cross-state passes.

A drying trend begins Thursday as the larger trough moves eastward allowing for a ridge of high pressure to build over the Pacific Northwest. Shower activity is expected in the Puget Sound Region, southwest part of the state, Okanogan Highlands, Palouse, and Blue Mountains during the day on Thursday but precipitation values will be far lower than on Wednesday.

By Friday, rain and mountain snow showers should be finished allowing for a pleasant start to the weekend. The ridge is also expected to spread above average temperatures across the state, especially for Eastern Washington. Afternoon highs look to peak a few degrees above average along the I-5 corridor on Saturday and around five to ten degrees above average on Sunday East of the Cascades. A few low elevation locations such as the Tri-Cities and Clarkston may even hit 70 on Sunday. Meanwhile west of the Cascades, the next disturbance begins working its way ashore with rain and mountain snow Sunday afternoon. Model guidance has this cold front crossing the Cascades to bring rain and mountain snow to the east half of the state Monday.


Important Points About Next Week's Weather

South Central Washington
Remainder of the Week
  • Wind: W and light Tue, SW and windy Wed, W with breezy areas Thu, SW with breezy areas Fri.
  • Precipitation: Isolated showers possible Wed, otherwise dry.
  • High Temps: Near 60 Tue-Wed, upper 50s Thu, low 60s Fri.
  • Low Temps: Low 30s Mon night, mid 30s Tue night, upper 30s Wed night, mid 30s Thu-Fri nights.
  • Sky Cover: Clear Tue, mostly cloudy Wed-Thu, clear Fri.
Weekend
  • Wind: Light and variable Sat becoming S and windy Sun.
  • Precipitation: Dry conditions expected.
  • High Temps: Mid 60s Sat, upper 60s Sun.
  • Low Temps: Near 40 Sat & Sun nights.
  • Sky Cover: Clear to partly cloudy.

North Central Washington
Remainder of the Week
  • Wind: W and light Tue, SW and windy in the Basin Wed, W with breezy areas Thu, SW with breezy areas Fri.
  • Precipitation: Possible rain and mountain snow Wed-Thu, highest chance in mountainous areas.
  • High Temps: Upper 50s Tue, mid 50s Wed, upper 50s Thu, near 60 Fri. Cooler in higher terrain.
  • Low Temps: Near 30 Mon night, low 30s Tue-Thu nights, mid 30s Fri night. Cooler in higher terrain.
  • Sky Cover: Clear Tue, mostly cloudy Wed, partly cloudy Thu, clear Fri.
Weekend
  • Wind: Light and variable Sat becoming S and windy Sun.
  • Precipitation: Dry conditions expected.
  • High Temps: Low 60s Sat, mid 60s Sun. Cooler in higher terrain.
  • Low Temps: Upper 30s Sat-Sun nights. Cooler in higher terrain.
  • Sky Cover: Partly cloudy.

Eastern Washington
Remainder of the Week
  • Wind: W and light Tue, SW and windy Wed, W with breezy areas Thu, SW with breezy areas Fri.
  • Precipitation: Isolated showers tapering off Mon night, scattered showers Wed-Thu.
  • High Temps: Mid 50s Tue, upper 40s Wed, low 50s Thu, mid 50s Fri. Warmer in the Lewis & Clark Valley.
  • Low Temps: Upper 20s Mon night, low 30s Tue-Fri nights. Warmer in the Lewis & Clark Valley.
  • Sky Cover: Partly cloudy Tue, mostly cloudy Wed-Thu, partly cloudy Fri.
Weekend
  • Wind: Light and variable Sat becoming S and windy Sun.
  • Precipitation: Dry conditions expected.
  • High Temps: Near 60 Sat, mid 60s Sun. Warmer in the Lewis & Clark Valley.
  • Low Temps: Mid 30s Sat & Sun nights. Warmer in the Lewis & Clark Valley.
  • Sky Cover: Partly cloudy.

Western Washington
Remainder of the Week
  • Wind: Light and variable Tue, S with breezy areas Wed, N/W and breezy on the Coast Thu, light and variable Fri.
  • Precipitation: Rain and mountain snow showers Wed-Thu.
  • High Temps: Mid 50s Tue, low 50s Wed-Thu, mid 50s Fri. Cooler in higher terrain.
  • Low Temps: Upper 30s Mon night, low 40s Tue-Fri nights. Cooler in higher terrain.
  • Sky Cover: Mostly cloudy through Thu, partly cloudy Fri.
Weekend
  • Wind: Light and variable Sat, S and windy Sun.
  • Precipitation: Rain and mountain snow showers beginning Sun.
  • High Temps: Upper 50s Sat, mid 50s Sun. Cooler in higher terrain.
  • Low Temps: Near 40 Sat night, upper 30s Sun night. Cooler in higher terrain.
  • Sky Cover: Partly cloudy Sat, mostly cloudy Sun.

Like us on Facebook at https://www.facebook.com/AgWeatherNet
Follow us on Twitter at https://www.twitter.com/AgWeatherNet
Washington State University