Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Seattle Washington
324 PM PDT sun Jul 24 2016
Synopsis...high pressure will bring dry and mild weather tonight and
Monday. A weak system will move by Monday night bringing some
marine air into the interior for Tuesday. The ridge will
strengthen Wednesday into the end of the work week with the
warmest temperatures of the month expected Thursday and Friday.
Short term...high pressure is giving US dry and mild weather
across western Washington today. Skies are mostly clear but
stratus clouds will reform along the coast overnight. The ridge
will flatten on Monday while a weak disturbance tracks through the
region, however it is still looking dry across the County Warning Area. A strong
onshore push will develop Monday night into Tuesday for increasing
clouds and cooler conditions. High temperatures on Tuesday will
be closer to normal. There ridge will then rebuild over the area
on Wednesday. There will be areas of low clouds Wednesday
morning, otherwise expect clearing in the afternoon with another
mild day on tap. 33
Long term...a strong upper level ridge over the west will bring
warm temperatures to much of the area Thursday and Friday. High
temperatures in the interior will be in the 80s with a few low 90s
possible. The low level flow will remain onshore with cooler
conditions by the water - highs mainly in the 70s.
An upper level trough will track down from Alaska next weekend,
while kicking the ridge east and out. This will end our warm spell
with temperatures trending back toward normal. 33
Aviation...high pres aloft will remain over the region for light
wly flow aloft through Monday. The low level onshore pres gradient
will strengthen on Monday.
Expect areas of LIFR cigs/IFR vsbys over the coast after 0600
UTC, reaching kshn after by 1200 UTC. Also, expect areas of LIFR
cigs/IFR visibilities over the Strait of Juan de Fuca and in the vicinity
of Whidbey Island after 0900 UTC.
Ksea...VFR. Winds will remain nly.
Marine...high pressure offshore with lower pressure east of the
Cascades will result in continued onshore flow through Wednesday.
The flow will strengthen on Monday for gale force winds over parts
of the Strait of Juan de Fuca Monday night. Expect the flow to
weaken Tuesday and Wednesday.
Pz...Small Craft Advisory until 11 PM PDT this evening for coastal
waters from James Island to Point Grenville out 10 nm-
coastal waters from Point Grenville to Cape Shoalwater out
Small Craft Advisory until midnight PDT Monday night for coastal
waters from Cape Flattery to James Island 10 to 60 nm-
coastal waters from James Island to Point Grenville 10 to
60 nm-coastal waters from Point Grenville to Cape
Shoalwater 10 to 60 nm.
Gale watch from Monday evening through late Monday night for
central U.S. Waters Strait of Juan de Fuca-East Entrance
U.S. Waters Strait of Juan de Fuca.
Small Craft Advisory until 5 am PDT Monday for central U.S.
Waters Strait of Juan de Fuca-East Entrance U.S. Waters
Strait of Juan de Fuca.
You can see an illustrated version of this discussion at