AgWeatherNet Weekly Weather Outlook for July 29 to August 4, 2017

Major Heat Wave Likely Next Week

Nic Loyd, Meteorologist, 509-786-9357

A potentially significant heat wave is likely to develop next week, as a strong ridge of high pressure builds into Washington starting on Monday. Although there is still uncertainty in the details, some manifestation of very hot weather is expected for most of the state. The trend has been for even hotter conditions later next week in more recent model runs. Although eastern temperatures continue to look oppressive, and could even surpass 110 degrees in spots, the situation is especially interesting west of the Cascades.

Until quite recently, it appeared that western Washington, while hot, would escape the most extreme conditions. Now, however, the odds have substantially increased for a period of neutral or briefly offshore air flow. If that scenario unfolds, the interior west and maybe even the coast will become very warm. The ultimate degree of marine air influence will depend upon the exact setup of the high pressure ridge and the associated circulation features. Therefore, the presence of a shallow sliver of maritime salvation along the coast is a tenuous proposition at this time.

In any event, there is still no sign of rain in our future, so the main issues in the coming days will be the timing and magnitude of the heat.

An estimate for the peak temperatures (likely around the middle to latter part of next week) by region is as follows:
Coast: 70s/80s
Interior Western Washington: Mid 80s near water in the north to low 100s around Vancouver
Central Washington: 105-112
Eastern Washington (Pullman and Spokane): 100-107

It is too early to say for certain, but western areas could become cooler by next Friday. However, locations east of the Cascades may have only just leveled off at that point. Overall, the hottest weather so far this year is expected next week, and Washingtonians should be prepared for a prolonged and potentially dangerous hot spell.

Temperatures
  • Very warm on Saturday, and then very hot next week.
  • Possibly less hot late in the period, mainly near the coast.

Precipitation
  • Mostly dry.

Wind
  • Generally light, but possibly breezy at times.

8 to 14 Day Outlook - August 5, 2017 to August 11, 2017
  • Overall, above average temperatures and below average precipitation are expected during the 8 to 14 day time frame.

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 mid 90s and lows in the mid 50s to low 60s.
Weekend
  • Mostly dry.
  • Highs in the mid to upper 90s on Saturday, and mid 90s to around 100 on Sunday.
  • Lows in the mid 50s to mid 60s on Saturday morning, and upper 50s to mid 60s on Sunday morning.
Next Week
  • Mostly dry.
  • Highs in the mid 90s to low 100s on Monday, and then warmer.
  • Lows in the upper 50s to 60s on Monday morning, and then warmer.

North Central Washington
  • Normal conditions for this time of the year would be highs in the upper 80s to low 90s and lows in the mid 50s to low 60s.
Weekend
  • Mostly dry.
  • Highs in the 90s on Saturday, and mid to upper 90s on Sunday.
  • Lows in the upper 50s to mid 60s on Saturday morning, and 60s on Sunday morning.
Next Week
  • Mostly dry.
  • Highs in the mid 90s to around 100 on Monday, and then warmer.
  • Lows in the 60s to low 70s on Monday morning, and then warmer.

Eastern Washington
  • Normal conditions for this time of the year would be highs in the mid 80s to around 90 and lows in the 50s.
Weekend
  • Mostly dry.
  • Highs in the low to mid 90s on Saturday, and 90s on Sunday.
  • Lows in the 50s on Saturday morning, and 50s to mid 60s on Sunday morning.
Next Week
  • Mostly dry.
  • Highs in the mid 90s to around 100 on Monday, and then warmer.
  • Lows in the mid 50s to mid 60s on Monday morning, and then warmer.

Western Washington
  • Normal conditions for this time of the year would be highs in the 70s to low 80s and lows in the 50s.
Weekend
  • Mostly dry.
  • Highs in the 70s to 80s, except possibly cooler at the coast.
  • Lows in the upper 40s to 50s on Saturday morning, and 50s to low 60s on Sunday morning.
Next Week
  • Mostly dry.
  • Highs in the 80s to low 90s on Monday (except cooler at the coast), and then warmer, and possibly cooler later in the week.
  • Lows in the 50s to low 60s on Monday morning, and then warmer.


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