192 
FXUS66 KPDT 110927
AFDPDT

Area Forecast Discussion
National Weather Service Pendleton OR
227 AM PDT Mon Sep 11 2023

.SHORT TERM...Today through Wednesday night...Deterministic models
and ensembles remain in excellent agreement on the evolution of
the 500 mb pattern over the next few days which gives high
confidence in the forecast. A shortwave trough will move across 
WA today causing a weak marine push and breezy winds this 
afternoon and evening through the Columbia Gorge and Kittitas 
Valley. Winds in these locations will be 15 to 25 mph sustained 
with the ECMWF ensemble showing mean peak gusts around 30 mph 
this afternoon and evening. High temperatures today will be in the
low to mid 80s with 70s in the mountains. On Tuesday another 
stronger shortwave will begin to move across the area during the 
evening and clear the region Wednesday morning. This will result 
in a slightly stronger marine push Tuesday with winds of 18-30 
mph and gusts to around 35 mph. The probability of maximum 
sustained winds of 20 mph or greater Tuesday is 80% at KELN and 
73% at KDLS. Where winds will be strongest Tuesday afternoon 
humidities will be 30-35%. Thus critical fire weather conditions 
are not expected at this time. On Tuesday night there will be a 
20-40% chance of light showers along the Washington Cascade 
crest...mainly over northwestern Yakima and western Kittitas 
Counties otherwise it will be dry. Wednesday and Wednesday night 
a ridge of high pressure will build over the region from off the 
Pacific bringing continued dry conditions and near normal 
temperatures. 78 


.LONG TERM...Thursday through Monday...Models remain in good 
agreement with the development of high pressure on Thursday. Dry 
conditions and warming temperatures will result from this pattern, 
with the area of high pressure remaining through Sunday/Monday. 
Temperatures through the period will reach 10 to 15 degrees above 
normal, with the warmest temperatures expected Saturday and Sunday 
for much of the area. Sunday will see a swath of moderate confidence 
(60-70%) in temperatures around 90 degrees across the Columbia 
Basin, especially across the Tri-Cities and areas north. 

An approaching system late Sunday and into Monday will push the warm 
and dry conditions further east, with a slight chance (15-30%) of 
showers developing across the Oregon and Washington Cascades. 
Temperatures will see a dip of around 5 degrees from this system on 
Monday, though still remain around 5 to 10 degrees above normal. 
Branham/76

&&

.AVIATION...Previous Discussion...06Z TAFs...VFR conditions will 
continue to prevail during the next 24 hours through 06Z Monday 
evening. Cigs will mostly be 200-250, if any, with FEW-SCT clouds at 
100. Winds will increase to 12-22 Kts, with gusts to 22-32 Kts at 
KDLS. Elsewhere, it will become breezy at times after 18Z at KALW, 
KPDT, KRDM, and KBDN, with wind gusts of 12-22 Kts. KPSC and KYKM 
will only have modest wind increases. 88

&&

.PRELIMINARY POINT TEMPS/POPS...
PDT  83  53  79  54 /   0   0   0   0 
ALW  85  58  81  56 /   0   0   0   0 
PSC  87  60  84  58 /   0   0   0   0 
YKM  84  52  82  51 /   0   0   0   0 
HRI  87  59  84  57 /   0   0   0   0 
ELN  80  54  80  54 /   0   0   0   0 
RDM  81  47  78  45 /   0   0   0   0 
LGD  84  52  79  50 /   0   0   0   0 
GCD  87  50  82  48 /   0   0   0   0 
DLS  81  58  81  59 /   0   0   0   0 

&&

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

$$

SHORT TERM...78
LONG TERM....76
AVIATION...88