National Weather Service Area Forecast Discussion for Long Beach, WA USA

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Area Forecast Discussion...updated
National Weather Service Portland, OR or
1046 am pdt thu jun 17 2021

updated aviation discussion

.synopsis..ridging will build across the pacific nw through early
next week resulting in abnormally dry and warm weather. temperatures
may reach near record levels on monday.

.short term...today through saturday...satellite imagery shows
widespread clear skies and is expected to have little to no change
over the next 48 hours for inland locations. there could be a weak
marine push this morning and friday morning, which will bring some
marine stratus along the coast through the early morning. however,
these clouds will quickly dissipate through the morning. the
reason for the very little change in the forecast is that weak
ridging persists across the pacific nw, while at the same time a
family of upper level lows move across the british columbia.

overall, not expecting much if any fog development tonight for inland
locations. however, there is the potential for some patchy fog/marine
stratus development along the coast. some very low level clouds/fog
can already be seen around newport, or and can be seen spreading
along the coast.

slightly warmer temperatures are expected today as the upper level
ridge mentioned above strengthens slightly. friday will likely be
slightly cooler as a shortwave trough quickly moves across the area.
however, these slightly cooler temperatures will be short lived as
another ridge builds across the region for the start of the weekend.
high temperatures on saturday with daytime highs returning to the low
to mid 80s. at this time there is no precipitation is in the forecast
so, expect warm, dry and sunny days through saturday. /42

.long term...no changes. previous discussion follows...saturday night
through tuesday...warmer temperatures are expected through the
weekend and into next week as a strong upper level ridge of high
pressure builds over the area. there are some model disagreements on
how strong the high pressure will build too, but there is good
agreement that the upper ridge axis will move across the area on
monday for the warmest temperatures. ensemble guidance shows a range
for potential temperature outcomes, but are in fair agreement that
inland temperatures will reach at least 90 degrees sunday and monday.
nbm guidance shows there is a 70 percent chance that temperatures
will exceed 90 degrees in portland on sunday and a
70 percent chance that temperatures will exceed 95 degrees on monday.
north to northwest winds will maintain cooler temperatures for the
coast, but the coast will still be warm with afternoon temperatures
likely warming to around 80 degrees. nbm indicates there is a 60
percent chance that temperatures in astoria will exceed 80 degrees
sunday and monday.

models forecast an upper low developing off of the california coast
on monday. this low will move north towards the pacific nw monday
night, and likely return marine stratus to the coast. increased
clouds and a cooler airmass will result in cooler temperatures
tuesday afternoon, although they will likely still be well above what
is typical for mid june. if this low tracks close to or near nw
oregon as it moves inland mid next week, it may generate showers
across the area. since this is not expected to happen within the 7
day forecast period, pops have not been added to the forecast yet.

&&

.aviation...vfr conditions will continue under clear skies for
the next 24 hours. the exception will be along the coast, where
marine stratus with cigs between 500-1000 feet should return
between 09-12z, beginning along the north or coast first. this
marine push looks to be fairly weak, so would not expect stratus
to push into the willamette valley. href guidance supports this
by showing marine stratus struggling to push down the columbia
river and through the coast range gaps, possibly making it as
far inland as the kelso area. otherwise, expect northwest to
north winds to increase later this afternoon with gusts between
20 and 30 kt at the coast and 15 to 20 kt for the willamette
valley.

for detailed regional pac nw aviation weather information, go
online to: https://weather.gov/zse

kpdx and approaches...vfr expected for the next 24 hours. light
winds give way to breezy conditions from 21-06z. -tk

&&

.marine...typical summertime weather pattern with thermally
induced surface trough over the northern ca/southern or coast
and high pressure to the north and west. this setup will bring
a northerly flow pattern through the weekend, with the breeziest
conditions expected during the afternoon and evening hours each
day. the strongest winds should occur over the central waters,
especially to the south of cape foulweather. this area should see
gusts 25 to 30 kt thursday. on friday as the pressure gradient
strengthens a bit more will see more widespread 25 to 35 kt gusts
so the small craft advisory for all zones look good. aside from
the breezy winds, expect seas to range between 3 and 5 feet
through thursday night before increasing to 6 to 8 feet friday
evening. /mh -tk

&&

.pqr watches/warnings/advisories...
or...none.
wa...none.
pz...small craft advisory from 5 am friday to 5 am pdt saturday for
     coastal waters from cape shoalwater wa to cascade head or
     out 60 nm.

     small craft advisory from 2 pm this afternoon to 5 am pdt
     saturday for coastal waters from cascade head or to
     florence or out 60 nm.

&&

$$

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