Area Forecast Discussion
Issued by NWS Seattle/Tacoma, WA

Current Version | Previous Version | Text Only | Print | Product List | Glossary Off
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50

FXUS66 KSEW 222148

Area Forecast Discussion
National Weather Service Seattle WA
248 PM PDT FRI JUL 22 2016

.SYNOPSIS...Isolated showers will diminish this evening across
Western Washington. High pressure will bring dry and mild weather
this weekend. The ridge will strengthen over the region next week
for a warming trend.


.SHORT TERM...The upper level trough that brought showers and
thunderstorms to Western Washington early today has now pushed
east of the Cascades. Showers have been winding down across the
westside with just isolated showers through this evening, mainly
along the coast and in the Cascades.

An upper level ridge will start to build over Western WA this
weekend for drier and warmer conditions. There will be morning
low clouds Saturday morning but we should see some clearing in the
afternoon. Onshore flow is weaker on Sunday for generally less
clouds in the interior. Expect highs in the 70s to lower 80 on
Sunday, with upper 60s to low 70s on the coast.

The ridge will flatten a bit as we move into Monday but we are
still looking dry and mild. A weak cold front will move inland
Monday night for increasing onshore flow. This will likely lead to
more clouds and slightly cooler weather on Tuesday. However, highs
on Tuesday are still close to normal. 33

.LONG TERM...High pressure across the West will lead to dry and
stable weather through much of next week. This pattern is
dominated by a strong ridge anchored over the Southwest, while
arcing north through the Pac NW. The 500 mb height field is in the
lower 590s dam over the region. Expect a warming trend through the
period, likely peaking on Thursday and Friday with highs in the
80s to lower 90s. The low level flow is still onshore for mainly
late night and morning clouds along the coast, along with
temperatures in the 60s to mid 70s. A weak trough may break the
ridge down next weekend with temperatures trending back to normal.


.AVIATION...High pressure aloft will prevail over the region
through Saturday for NW flow aloft. Contd low level onshore flow.
Not anticipating much clearing over the area. Expect areas of MVFR
cigs to become more widespread overnight. There will be localized
IFR CIGs/MVFR VSBYs. The mtns will be partially obscd.

KSEA...CIGs will lower into the MVFR category range as early as
0600 UTC. Winds will remain southerly. Expect VFR conditions to
return after 1800 UTC Saturday.


.MARINE...High pressure centered offshore with lower pressure
east of the Cascades will maintain onshore flow of varying
strength through early next week.


.SEW Watches/Warnings/Advisories...
PZ...Small Craft Advisory until 5 AM PDT Saturday 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 is the U.S. government's official web portal to all federal, state and local government web resources and services.