AgWeatherNet Weekly Weather Outlook for August 4 to August 10, 2012

Hottest Weather of the Year in Western Washington This Weekend; 100s Return to Central WA

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

Hot weather is coming to Washington this weekend, and it will continue through early next week in eastern Washington. Unlike the July 8th heat wave, offshore flow will allow heat to spread to all areas on Saturday, including the coast. Long Beach did not climb above 67 degrees during July, but that will change on Saturday. In western Washington, the warmest temperatures will range from the mid 90s to around 100 in the Vancouver area, to the 80s in coastal areas and around the San Juan Islands. Saturday will be a rare summer day where afternoon temperatures in parts of western Washington will be similar to or possibly warmer than areas east of the Cascades. As usual, the coast will experience heat for a brief time before the thermal trough moves inland later on Sunday. Cooling will spread up the coast from south to north, as the flow shifts back around to onshore during the day. By contrast, inland areas will be hot for a longer time, before some relief arrives next week. Highs will peak in the upper 90s to mid 100s in central Washington, and mid to upper 90s in eastern Washington around the Pullman area on Sunday. There is also a slight chance of thunderstorms around Sunday or Monday, as southerly flow brings warm and unstable air into the region. However, unlike mid July, there is no organized low pressure area to contribute moisture and dynamics to the atmosphere, so severe weather should not pose a problem. Storms that occur may be high-based and dry, which would increase the danger of fires due to the dry vegetation in the region. Next week, mainly dry and warm southwesterly flow will cause more seasonal weather in western Washington, although heat will continue in eastern Washington.

Temperatures
  • Above normal.
  • The heat will peak this weekend in western Washington.
  • The heat will peak late this weekend and early next week in eastern Washington.
  • Significant cooling will occur at the coast later on Sunday, and in interior western Washington on Monday.
  • Slight cooling will spread east of the Cascades next week.

Rainfall
  • Mostly dry through the period.
  • A slight chance of isolated thunderstorms around Sunday or Monday.

Wind
  • Generally light.
  • Occasionally breezy during the marine push 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 upper 80s to around 90 and lows in the 50s to around 60.
Weekend
  • Mostly sunny and dry.
  • Highs in the 90s to low 100s on Saturday, and upper 90s to mid 100s on Sunday.
  • Lows in the mid 50s to mid 60s.
Next Week
  • Mostly sunny and dry.
  • Highs in the mid 90s to low 100s on Monday, and cooling toward the upper 80s to 90s later in the week.
  • Lows in the 60s to low 70s early, and cooling slightly later in the week.

North Central Washington
  • Normal conditions for this time of the year would be highs in the mid to upper 80s and lows in the upper 50s.
Weekend
  • Mostly sunny and dry.
  • Highs in the 90s to low 100s on Saturday, and mid 90s to mid 100s on Sunday.
  • Lows in the mid 50s to mid 60s.
Next Week
  • Partly sunny and dry.
  • Highs in the mid 90s to low 100s on Monday, and cooling toward the upper 80s to 90s later in the week.
  • Lows in the 60s to low 70s early, and cooling slightly later in the week.

Eastern Washington
  • Normal conditions for this time of the year would be highs in the mid 80s and lows in the low 50s.
Weekend
  • Mostly sunny and dry. Warmer on Sunday.
  • Highs in the low 90s on Saturday, and mid to upper 90s on Sunday.
  • Lows in the 50s.
Next Week
  • Partly sunny and dry.
  • Highs in the 90s early, and then 80s later in the week.
  • Lows in the mid 50s to low 60s early, and cooler later in the week.

Western Washington
  • Normal conditions for this time of the year would be highs in the 70s to around 80 (except upper 60s to around 70 at the coast) and lows in the 50s.
Weekend
  • Dry and hot on Saturday. Similar temperatures on Sunday, except cooler at the coast.
  • Highs in the 90s, except 80s north of Seattle and near water on Saturday.
  • Highs in the 90s inland, and much cooler at the coast later on Sunday.
  • Lows in the mid 50s to mid 60s.
Next Week
  • Mostly dry. Morning low clouds returning during the week, especially at the coast.
  • Highs in the 70s, except mid 80s around Vancouver, and 60s to low 70s at the coast early in the week.
  • Highs in the 70s later in the week, except 60s at the coast.
  • Lows in the 50s.
Washington State University