AgWeatherNet Weekly Weather Outlook for May 12 to May 18, 2018

Heat Returns This Weekend; Slight Relief Possible Later Next Week

Nic Loyd, Meteorologist, 509-786-9357

An early season heat wave is expected for much of the region during the Sunday through early next week timeframe. Widespread 80s and even a few 90s are anticipated for highs, while low temperatures look to continue to climb as well. Otherwise, largely dry weather and only modest breezes are predicted to occur.

Initially on Saturday, a building high pressure ridge from the west and north will usher in the beginnings of a warm spell, even as northerly winds persist in some areas. Please do not be fooled, however, as these shall be warm winds. Interestingly, given the presence of a low pressure system over the Great Basin, the slowest to warm sites may be those in southeastern Washington.

The heat is likely to peak around early next week. Still, there is no sign of a major cool down in the near future, at least in the east. Rather, it seems that onshore flow and cooler western highs around early to mid next week may eventually give way to less hot conditions statewide late in the period. A weak and slow moving low pressure area is forecast to move inland to our south later next week, but exactly how it ultimately progresses is not clear. If its track is rather close to Washington, there could be increased shower and thunderstorm chances, along with breezy winds. In any case, general indicators are for well above normal temperatures in the coming days and weeks.

One mitigating factor regarding the heat should be the absence of a strong, full-latitude high pressure ridge near the Northwest. Despite the warm air mass overall, the possibility of periodic low pressure over the Southwest US, and also cooler air to our north in Canada, suggests that notably above normal (yet not record breaking) heat is likely at times.


Key Points:

  • Becoming drier and warmer this weekend.
  • Generally very warm next week.
  • Cooler western highs by mid next week, and then less hot in the east and at night late in the period.
  • A slight chance of showers and thunderstorms, and also increased winds later next week.


Temperatures
  • Becoming warmer this weekend.
  • Hot early next week, and then slightly cooler.

Precipitation
  • Mostly dry.
  • A slight chance of showers or thunderstorms for mid to late next week.

Wind
  • Breezy on Saturday, and possibly again later next week.

8 to 14 Day Outlook - May 19, 2018 to May 25, 2018
  • 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 low to mid 70s and lows in the 40s to low 50s.
Weekend
  • Mostly dry.
  • Highs in the low to mid 80s on Saturday, and mid to upper 80s on Sunday.
  • Lows in the mid 40s to low 50s on Saturday morning, and mid 40s to mid 50s on Sunday morning.
Next Week
  • Mostly dry. A slight chance of showers later in the week.
  • Highs in the mid 80s to low 90s on Monday, and then warmer, and cooler later in the week.
  • Lows in the upper 40s to mid 50s on Monday morning, and then warmer, and possibly cooler later in the week.

North Central Washington
  • Normal conditions for this time of the year would be highs in the low 70s and lows in the mid to upper 40s.
Weekend
  • Mostly dry.
  • Highs in the 80s on Saturday, and mid to upper 80s on Sunday.
  • Lows in the upper 40s to mid 50s on Saturday morning, and 50s on Sunday morning.
Next Week
  • Mostly dry. A slight chance of showers later in the week.
  • Highs in the mid 80s to low 90s on Monday, and then warmer, and cooler later in the week.
  • Lows in the 50s to low 60s on Monday morning, and then warmer, and possibly cooler later in the week.

Eastern Washington
  • Normal conditions for this time of the year would be highs in the mid 60s to low 70s and lows in the 40s.
Weekend
  • Mostly dry.
  • Highs in the 70s to low 80s on Saturday, and mid 70s to mid 80s on Sunday.
  • Lows in the 40s on Saturday morning, and 40s to mid 50s on Sunday morning.
Next Week
  • Mostly dry. A slight chance of showers later in the week.
  • Highs in the 80s on Monday, and then warmer, and cooler later in the week.
  • Lows in the mid 40s to 50s on Monday morning, and then warmer, and possibly cooler later in the week.

Western Washington
  • Normal conditions for this time of the year would be highs in the 60s and lows in the 40s to around 50.
Weekend
  • Mostly dry.
  • Highs in the mid 70s to around 80 on Saturday, and upper 70s to 80s on Sunday, except cooler at the coast.
  • Lows in the mid 40s to low 50s on Saturday morning, and upper 40s to mid 50s on Sunday morning.
Next Week
  • Mostly dry. A slight chance of showers later in the week.
  • Highs in the upper 70s to mid 80s on Monday, except cooler at the coast, and then cooler region-wide by Tuesday.
  • Lows in the 50s early, and possibly cooler later in the week.

Happy Mother's Day from AgWeatherNet!

Washington State University