000
FXUS66 KPDT 011010
AFDPDT

Area Forecast Discussion
National Weather Service Pendleton OR
210 AM PST Mon Mar 1 2021

.SHORT TERM...Today through Wednesday night...the short term
period will be dominated by a dry west or southwest flow pattern
with little in the way of weather. It looks to be fairly quiet.
The only concerns now in the short term is strong winds in the
southern Grande Ronde Valley, where there is currently a Wind
Advisory in effect until noon PST today. A high pressure ridge
axis that is over the PacNW will shift eastward today and cause
the flow to become southwesterly. This will bring warmer
temperatures northward into the region for a gradual warming trend
that will continue into the extended forecast period. By Monday
afternoon the flow aloft will become more westerly, which will
more enable weather systems to move into the region. However, any
weather system that does will be rapidly weakened and dried out by
the Cascades, leaving very little moisture for the east
side...including the CWA. This westerly zonal flow pattern will
persist through Tuesday night, and then the flow will become
southwest again as an upper ridge builds to the east, and an upper
trough deepens over the northern Pacific. However, this flow
pattern will only keep the region warmer, but there will be very
little to any moisture to cause any impactful weather over the CWA
during the short term. 88

.LONG TERM...Thursday through Monday...Warming trend in store for
the region as a deepening trough off the Pacific coast ushers in SW
flow aloft over the forecast area. Ensembles in good agreement of
this SW flow pattern sticking around through the long term, with
main disagreement stemming from when the trough moves on shore over
the weekend. Current guidance suggesting bulk of precip chances will
remain in the mountains, with perhaps a few spillover showers in the
eastern foothills, however QPF ensembles not too bullish on amounts
thus far. Deterministic guidance has the trajectory of the trough
axis such that most of the associated lift lies at the Cascades
westward, but will keep an eye on how the track of this low changes
in the models through the week.

Yet another trough looks to form behind this next weekend`s system,
maintaining a persistent mild trend in temperatures, as well as a
slight chance for precip, primarily in the mountains. Models have
been more aggressive with the warming expected later this week, with
NBM suggesting mid 60s for highs by Friday in the lower elevations.
Temps decrease over the weekend as the cold front associated with
the trough passes through, but highs struggle to dip down below
the 50s through the long term in the lower elevations. As mountain
snow melts under these warming conditions, will start to see
slight rises in rivers and streams, however guidance thus far are
not suggesting any significant precip events through the next
week. 74

.AVIATION...12z TAFs...VFR conditions expected through the period.
High pressure over the area will keep skies mostly clear and winds
less than 10 kts. Could see locally breezy SE winds for PDT/ALW with
gusts around 15-20 kts, but these winds will largely subside by
Monday evening. 74

&&

.PRELIMINARY POINT TEMPS/POPS...
PDT  56  35  55  31 /   0   0   0   0
ALW  54  38  55  34 /   0   0   0   0
PSC  59  37  58  33 /   0   0   0   0
YKM  54  31  55  28 /   0   0   0   0
HRI  58  37  58  33 /   0   0   0   0
ELN  50  32  49  28 /   0   0   0   0
RDM  55  28  55  27 /   0   0   0   0
LGD  40  29  44  28 /   0   0   0   0
GCD  48  29  52  28 /   0   0   0   0
DLS  58  37  55  33 /   0   0   0   0

&&

.PDT WATCHES/WARNINGS/ADVISORIES...
OR...Wind Advisory until noon PST today for ORZ049.
WA...None.

&&

$$

SHORT TERM...88
LONG TERM....74
AVIATION...74

NWS PDT Office Area Forecast Discussion