505
FXUS66 KPDT 182133
AFDPDT

Area Forecast Discussion
National Weather Service Pendleton OR
233 PM PDT Fri Apr 18 2025

.SHORT TERM...Today through Monday...A positively tilted upper
level ridge stretching from the Pacific Northwest through northern
Saskatchewan has placed the region in a dry, northerly flow
regime this afternoon. As of 2 PM PDT, temperatures are running 5
to 10 degrees warmer than this time yesterday with current
temperatures in the 60s. Temperatures will continue to warm for
the next couple hours with widespread highs for the Columbia Basin
on track to warm into the upper 60s and lower 70s.

The upper level ridge will shift to the southeast overnight as a
cold front moves through the region Saturday morning. While a
band of light precipitation will accompany the cold front passage
and showers develop behind the front over the Blues, winds will be
the primary hazard. Westerly winds look to increase through the
Kittitas Valley and the eastern Gorge) by mid Saturday morning as
the surface pressure gradient tightens behind the cold front.
Winds will remain breezy through the afternoon with gust 30 to 45
mph through the gaps. Breeziness will also be felt in the
neighboring valleys and the Columbia Basin with gusts 25 to 40 mph
in the afternoon.

Weather will remain unsettled as a broad upper level trough digs
into the northwest on Sunday. A shortwave embedded within the main
flow will bring precipitation primarily to the mountains. Most
lowland locations will miss out on the rain potential with the
best chances (20 to 25 percent) for 0.01 inches across the
foothills of the northern Blues. Breezy to locally gusty winds
(gusts 30-45mph for the Cascade gaps, 25-40 mph for the Columbia
Basin) will continue Sunday afternoon surface pressure gradients
remain tightened across the forecast area. Temperatures will cool
into the 50s and 60s for Sunday and Monday.

.LONG TERM...Tuesday through Saturday...Quiet weather is
anticipated for midweek with dry, split flow over the northwest.
Confidence in the pattern wanes by Friday as global ensembles
diverge on the details as the next weather system approaches the
western US. For Tuesday through Thursday, temperatures will
gradually warm under this pattern. Tuesday morning looks to be the
coldest morning of the period with lows in the low to mid 30s for
the Yakima and Kittitas Valleys. /OTX


&&

.AVIATION...18Z TAFs... VFR conditions will continue through the
forecast period. Mid to high level clouds will begin to move in
from the west around 00Z ahead of an approaching cold front. Cold
front passage will bring a 15 to 25 percent chance of light rain,
but confidence is too low at this moment to include in TAFs. West
to northwest winds will increase through the Columbia River Gorge
and the Cascade Valleys behind the cold front passage after 12Z
with sustained speeds 10-20 knots and gusts up to 30 knots.


&&

.PRELIMINARY POINT TEMPS/POPS...
PDT  44  68  40  61 /   0  20   0   0
ALW  47  67  42  60 /   0  30   0   0
PSC  46  73  41  66 /   0  20   0   0
YKM  48  72  40  65 /  10  10   0   0
HRI  47  72  41  65 /   0  20   0   0
ELN  47  64  41  59 /  20   0   0   0
RDM  38  67  32  61 /   0  10   0   0
LGD  37  62  34  57 /   0  20   0   0
GCD  37  63  33  60 /   0  20   0   0
DLS  49  67  43  61 /  10  20   0   0

&&

.PDT WATCHES/WARNINGS/ADVISORIES...
OR...None.
WA...None.
&&

$$

SHORT TERM...99
LONG TERM....99
AVIATION...99