Kennewick, Virginia 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

268
FXUS66 KPDT 190532
AFDPDT

Area Forecast Discussion
National Weather Service Pendleton OR
1032 PM PDT Fri Jul 18 2025

Updated Aviation Discussion

.AVIATION...06Z TAFS...VFR conditions to prevail through the
period. Passing system will continue to produce few-sct CIGS AOA
15-25kft AGL at most sites this late evening, with periods of
clear skies developing. Breezy winds 12-17kts with gusts to around
25kts will continue at site DLS overnight, increasing again to
20-25kts with gusts to around 30kts after 18Z tomorrow. Site PDT
winds will continue to be around 15kts with gusts up to 25kts
through 9Z, becoming 12kts or less. All other sites will see light
winds overnight. Tomorrow, winds will increase again to 12-20kts
with gusts to around 25kts late in the morning and afternoon at
sites PDT/RDM/BDN/YKM/ALW, with winds around 12kts at site PSC.
Lawhorn/82

PREV DISCUSSION... /issued 203 PM PDT Fri Jul 18 2025/

.DISCUSSION...Tonight through Friday. Key Messages...
 - Critical fire weather conditions this afternoon and evening
   with hot, dry, and windy conditions, except across northeast OR
   and the upper east slopes of the WA Cascades
 - Heightened fire weather conditions Saturday across the Lower
   Basin and Kittitas Valley
 - Slight chance of isolated thunderstorms over the WA Cascades
   and eastern mountains Monday
 - Cooler, near average Sunday into early next week with highs
   rebounding above average Wednesday onward with a drying trend
   late next week.

Latest water vapor imagery shows a shortwave trough descending
into WA with a low over British Columbia in tandem with
increasing mid-level flow spreading into south central WA. Latest
day cloud phase imagery shows largely clear skies outside south
central WA downstream of approaching high clouds. The shortwave
trough will continue dropping southeastward with its attendant
dry cold front crossing the area early tonight. Increasing W-SW
winds ahead of the front will be reinforced with the strongest
winds and gusts expected 5-11 pm today with minimum RH 10-20%
common across the lower elevations. Increased confidence, 80% or
higher, with gusts greater than 25 mph across the Lower Basin,
eastern Columbia Gorge, south central WA; highest gusts spilling
out of the eastern gorge into north central OR and the Kittitas
valley wherein daily peak gusts of 39 mph or more are anticipated
(80-100% chance). Winds will then subside and lessen gradually
overnight.

Despite cooler air mass post-frontal, a favorable overlap of
breezy winds and afternoon humidity is expected again as the
upper low sags to the southern BC-Alberta border. Of which,
elevated to locally critical fire weather conditions are expected
across a portion of the eastern Gorge into northern Sherman,
Gilliam, Morrow counties and Kittitas valley. Highs will drop 4-8
degrees tomorrow from today. Meantime, afternoon RHs will be near
to slightly above seen today across south central WA owing to
modest isentropic descent and drying via 305-310 theta surfaces as
seen among deterministic guidance. Breezy to gusty winds still
expected with modest pressure differences seen cross-Cascades
though flow aloft not as strong as this afternoon and evening.

Quiescent fire weather conditions Sunday-Tuesday with respect to
humidity and winds owing to a relaxed pressure gradient and more
BL moisture. With the upstream amplification of an upper ridge in
the eastern North Pacific and Gulf of Alaska late Saturday-Sunday,
mean mid-level troughing will take hold downstream over the
region Sunday-Tuesday. This with increased moisture and marginal
instability with gudience supporting robust precipitable waters in
place for this time of year will promote low chances, 10-25%, for
thunderstorms Monday across the eastern mountains and WA
Cascades, including chances for wetting rain as high as 30%. This
threat will then shift farther east Tuesday, and be confined to
the far eastern mountains.

Looking onward, ensemble guidance favors a building upper-level
ridge Wednesday-Thursday over the eastern CONUS with weak
troughing/zonal westerly flow over the region. Meantime,
clustering scenarios lean towards a warming and drying trend by
Friday in response to the most likely outcome of a southwest flow
regime taking hold by Friday (~75%). As such, drying and warming
trend is anticipated with highs reading few-several degrees above
average Wednesday-Friday. This scenario could result in elevated
fire weather concerns. Of which, latest hot-dry-windy reflects
this with GEFS showing increasing chance of exceeding the 75th and
90th percentile Wednesday and Thursday across the Lower Columbia
Basin and south central WA.

&&

.PRELIMINARY POINT TEMPS/POPS...
PDT  61  88  59  84 /   0   0   0   0
ALW  65  88  62  83 /   0   0   0   0
PSC  60  91  58  86 /   0   0   0   0
YKM  59  88  57  85 /   0   0   0   0
HRI  61  90  60  86 /   0   0   0   0
ELN  57  84  57  83 /   0   0   0   0
RDM  52  85  49  83 /   0   0   0   0
LGD  57  85  56  83 /   0   0   0   0
GCD  56  87  53  85 /   0   0   0   0
DLS  61  84  61  82 /   0   0   0   0

&&

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

$$

SHORT TERM...80
LONG TERM....80
AVIATION...82