AgWeatherNet Weekly Weather Outlook for September 22 to September 28, 2012

Warm and Smoky Weather This Weekend; Slight Improvement Next Week

Nic Loyd, Meteorologist, 509-786-9357
Gerrit Hoogenboom, Director, 509-786-9371

Fires continue to burn along the Cascade east slopes, as thick smoke plagues the Wenatchee area. Parts of eastern Washington will remain somewhat smoky this weekend. Warm temperatures will continue east of the Cascades on Saturday, with highs in the 80s, except cooler in areas of dense smoke. Sunday will be cooler in the south, while areas near the Canadian border will stay hot for one more day. One wild card this weekend is the possibility of high based thunderstorms, especially over the mountains, as an upper low drifts over Oregon. Any lightning would be disturbing for fire-fighting efforts in this exceptionally dry environment, although some clouds and slightly higher humidity in the south will be helpful.

Although little improvement is likely overall, slightly cooler air next week may ameliorate the fire danger. However, the changes will be only minimally beneficial, and certain areas will remain somewhat smoky next week. What is needed is a significant rain event, which will not occur during this outlook period. In general, highs next week should cool into the mid 70s to mid 80s, with lows in the 40s to mid 50s, as dry weather continues. Indications are that warmer weather could return later next week.

Western Washington will experience relatively smoke-free conditions, with seasonal and benign weather through the outlook period. Following a slight chance of showers this weekend and early next week, mostly dry weather is expected. Onshore flow will maintain a pattern of morning clouds and afternoon sunshine, with highs in the 60s to mid 70s.

Today (Friday, September 21st) is the final full day of astronomical summer, as the sun will be directly overhead at the equator tomorrow. Appropriately, the recent weather has certainly been very summer-like. Unusually warm and dry conditions have left timbers, grasses, and other fuels at record or near record dry levels, as high fire danger persists. Numerous active fires continue, while high pressure and stable conditions maintain smoky skies across the region. Luckily, a minor influx of cooler air will usher in a degree of relief in the coming days, just in time for the beginning of autumn.

Temperatures
  • Continued warm, with above normal temperatures in eastern Washington this weekend.
  • Slightly cooler, but still above normal next week.
  • Near normal in western Washington through the period.

Rainfall
  • A slight chance of showers in western Washington, as well as the southern half of eastern Washington this weekend.
  • A slight chance of rain early next week in western Washington.
  • Mostly dry next week overall.

Wind
  • Generally light.
  • Light breezes possible around Tuesday of next week.

Important Points about Next Week's Weather

South Central Washington
  • Normal conditions for this time of the year would be highs in the mid 70s and lows in the 40s.
Weekend
  • Partly cloudy, with areas of smoke. A slight chance of showers or thunderstorms, especially on Saturday night.
  • Highs in the low to mid 80s on Saturday, and upper 70s to low 80s on Sunday.
  • Lows in the upper 40s to 50s.
Next Week
  • Partly sunny, with decreasing smoke possible.
  • Highs in the mid 70s to mid 80s on Monday, and cooling into the mid 70s to low 80s by Tuesday.
  • Lows in the 40s to mid 50s.

North Central Washington
  • Normal conditions for this time of the year would be highs in the low to mid 70s and lows in the 40s.
Weekend
  • Partly sunny, except very smoky in the Wenatchee area.
  • Dry north of Omak, and a slight chance of showers or thunderstorms around Wenatchee.
  • Highs in the mid 80s to around 90 from Omak and northward, and mid 70s to low 80s in the thick smoke around Wenatchee.
  • Lows in the upper 40s to 50s.
Next Week
  • Partly sunny with areas of smoke, possibly decreasing during the week.
  • Highs in the upper 70s to mid 80s on Monday, except cooler around Wenatchee.
  • Cooling into the mid 70s to low 80s by Tuesday.
  • Lows in the 40s to mid 50s.

Eastern Washington
  • Normal conditions for this time of the year would be highs in the upper 60s to low 70s and lows in the low to mid 40s.
Weekend
  • Partly cloudy, with smoke at times. A slight chance of showers or thunderstorms, especially on Sunday.
  • Highs in the 80s on Saturday, and mid 70s to mid 80s on Sunday.
  • Lows in the mid 40s to mid 50s.
Next Week
  • Partly sunny, with decreasing smoke possible.
  • Highs in the mid 70s to low 80s on Monday, and cooling into the 70s by Tuesday.
  • Lows in the 40s to around 50.

Western Washington
  • Normal conditions for this time of the year would be highs in the mid 60s to low 70s and lows in the mid 40s to low 50s.
Weekend
  • Morning clouds, with possible afternoon sunshine.
  • A slight chance of showers.
  • Highs in the 60 to mid 70s.
  • Lows in the mid 40s to mid 50s.
Next Week
  • A slight chance of rain early in the week.
  • Morning clouds and periodic afternoon sunshine.
  • Highs in the 60s to mid 70s.
  • Lows in the mid 40s to mid 50s.
Washington State University