053
FXUS66 KPQR 171804 AAA
AFDPQR

Area Forecast Discussion...UPDATED
National Weather Service Portland OR
1104 AM PDT Mon Jun 17 2024

Updated aviation discussion...

.SYNOPSIS...One more seasonably cool day across the region as
showers continue to taper off behind departing low pressure.
Temperatures rebound back to normal on Tuesday, with high
pressure then bringing a stretch of hotter weather from
Wednesday through Saturday.

&&

.SHORT TERM...Now through Tuesday Night...Showers will continue to
taper off across most of the area today as the region settles into
drier northwest flow in the wake of the trough. A few showers may
linger as long as this evening along the Cascades, with additional
model QPF amounts ranging from a tenth to a quarter inch.
Temperatures will remain below normal for one more day as 850 mb
temps of 2-3 C correspond to highs in the mid to upper 60s in the
interior lowlands. Showers will come to an end across the area and
temperatures will rebound back to seasonal normals in the low to mid
70s on Tuesday as the influence of the upper trough continues to
diminish and 850 mb temps climb to around 8 C by Tuesday afternoon.
   /CB

.LONG TERM...Wednesday through Sunday...A stretch of
hotter weather begins on Wednesday as ensemble clusters and
deterministic solutions continue to depict a Rex Block type
pattern developing over the West Coast with an upper level ridge
over western Canada and a trough over California. Ensemble
solutions show good agreement on highs in the mid 80s across
much of the area on Wednesday afternoon, though low level
onshore flow will continue to moderate temperatures along the
coast. Temperatures look to peak Thursday into Friday as
probabilistic guidance continues to trend slightly higher, now
showing a 60-70 percent chance to reach 90 degrees from Portland
to Salem on both days and around a 35 percent chance to hit 90
at Eugene on Friday. The upper end of the guidance envelope has
also trended upward, as the chance to reach 95 degrees from
Portland to Salem has increased to 10-15 percent on Thursday and
around 30 percent on Friday. Despite these higher
probabilities, a look at individual ensemble members from the
GFS, Euro, and Canadian model suites still point to highs
ultimately maxing out in the low 90s both Thursday and Friday.
That said, the possibility for temperatures to reach as high as
the mid 90s later in the week can`t be discounted, particularly
for Friday. Guidance then indicates the start of a downward
trend on Saturday as temperatures drop back into the 80s, with
highs falling off into the 70s by Sunday as ensemble clusters
show good agreement on the next trough arriving over the region.
There is still uncertainty as to if this feature will be
accompanied by any meaningful precipitation, with the latest NBM
guidance holding onto a 20-30 percent chance of rain for the
northern coastal areas by Sunday. /CB

&&

.AVIATION...An upper level trough over the Pacific NW now east of
the Cascades. Isolated showers expected to continue to decrease
in the northwest flow behind the trough. A mix of MVFR and VFR is
expected to transition to VFR after 20Z Mon.

PDX AND APPROACHES...Brief MVFR with with passing showers through
about 20Z Mon, then should trend to VFR conditions. Guidance shows
about a 40% chance for MVFR cigs near 3000 ft after 12-15Z Tue in
the area. Northwest winds increase to around 6-8 kt this afternoon
into the evening before easing. /mh


&&

.MARINE...High pressure offshore is expected to persist through
the week. Northwest winds 10-15 kt across coastal waters today
becoming northerly on Tuesday. North winds begin to increase later
Tuesday afternoon as a thermal trough strengthens from northern CA
into southern OR. Expect will see periods of winds gusting up to
25 kt through Friday during the late afternoon and evenings. Seas
around 4 to 6 feet will generally be wind driven through the week.
/DH

&&

.PQR WATCHES/WARNINGS/ADVISORIES...

OR...None.
WA...None.
PZ...None.

&&

$$

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