Rip Current in Oregon, August 2, 2019

Area Forecast Discussion
National Service Portland OR
200 PM PDT Fri Aug 2 2019

.SYNOPSIS...Warm and dry conditions return this weekend under
building ridge of high pressure. This pattern will hold through the
early part of next week, then an increae in onshore flow will return
more clouds to the region with cooler temperatures late in the week.

&&

.SHORT TERM...Tonight trough Sunday...A baroclinic zone oriented
roughly from the northeast to southwest corners of the forecast area
Firday afternoon will slowly sag further se as it dissipates. A weak
upper level shortwave crosses Washington this evening, which will
tend to bring the chances for showers to an end this evening, but
with lingering low level moisture it may be difficult to completely
break up the clouds overnight inland. Some onshore component of a
northwest flow wil tend to keep more clouds along the coast
overnight.

While the low level flow remains onshore out of the northwst over
the next few days, building heights aloft will result in warmer
temperatures Saturday through Monday. An increasing northerly
component to the winds will likely limit the development of marine
clouds along the coast Saturday night and early Sunday, but then a
stronger onshore compoent Sunday night and Monday morning should
return more clouds back to the coastal areas. Inland areas under the
strengthening ridge are likely to see little to no morning marine
clouds Sunday and Monday.

.LONG TERM...Tuesday through Friday...Models continue to struggle
with the handling of the vertically stacked low aloft that sits well
off the west coast near the Alaska Panhandle. Within the flow around
this low, a shortwave (originating in central California) will
advect over the Cascade Range Wednesday into Thursday. As this
shortwave passes over the Pacific North West, south-southwesterly
flow will be dominate which in turn creates a favorable environment
for convective activity. Thus, there is a slight chance for some
thunderstorms along the Cascade Crest on Thursday, however
confidence is low. Elsewhere in northwestern Oregon/southwestern
Washington, there is a chance for scattered showers through Friday.
Meanwhile, the low aloft will drop south and advance towards the
coastline enhancing onshore flow. Clouds will move into the coastal
areas and push inland slightly on Wednesday into Thursday morning,
clearing out on Friday.

&&

.AVIATION...A decaying front continues to slowly push across the
area through the evening hours. Expect MVFR cigs to prevail at
coastal locations and location north of KSLE. Coastal locations
will likely see a mixture of MVFR/IFR conditions into early this
evening Saturday then becoming predominately IFR late tonight.

Northern inland locations should see MVFR conditions
predominately into the evening. Could see some brief scattering
out to VFR, but is expected to lower back to MVFR later tonight.
Southern inland locations should see VFR conditions with patchy
MVFR overnight.

Overall confidence is mixed for the forecast tonight, as partial
clearing could happen both along the coast and inland. Still
coastal areas should in general expect MVFR marine stratus
reform tonight. Inland locations should prepare for minimal
clearing especially north of KSLE and along the Columbia River
tonight.

KPDX AND APPROACHES...MVFR expected around the terminal through
early tonight. Minimal clearing is expected for the remainder of
the day. Marine stratus is expected to push in along the
Columbia River tonight, combined with the minimal clearing
expecting MVFR to persist through Saturday morning. /42

&&

.MARINE...Weak high pressure has filled in behind the front, and
north winds will slowly manifest across the waters through the
evening. Friday 12PM scatterometer pass shows northerly winds in
PZZ270 and those same winds slowly progressing towards PZZ275.
North winds will persist through the weekend and early next week
as high pressure remains across the Pacific NW and low pressure
to the south. A thermal trough over the northern California and
southern Oregon coast will strengthen over the weekend. This
scenario will bring Small Craft Advisory winds Saturday afternoon
and through Sunday morning.

Seas in the 3 to 5 ft range for the foreseeable future, with the
possible exception of Sat afternoon and evening, where stronger
wind waves will increase the seas a foot or two. /42

&&

.PQR WATCHES/WARNINGS/ADVISORIES...
OR...None.
WA...None.
PZ...Small Craft Advisory from 11 AM Saturday to 11 AM PDT Sunday
     for Coastal Waters from Cape Shoalwater WA to Florence OR
     out 10 NM.Waters from Cape Shoalwater WA to Cascade Head
     OR from 10 to 60 NM.

     Small Craft Advisory from 8 AM Saturday to 11 AM PDT Sunday for
     Waters from Cascade Head to Florence OR from 10 to 60 NM.

&&

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This discussion is for Northwest Oregon and Southwest Washington
from the Cascade crest to 60 nautical miles offshore. This area is
commonly referred to as the forecast area.