Hermiston, Oregon 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

762
FXUS66 KPDT 271714
AFDPDT

Area Forecast Discussion
National Weather Service Pendleton OR
1014 AM PDT Fri Jun 27 2025

Updated Aviation Discussion

AVIATION...18Z TAFs...VFR conditions to prevail through the
period. CIGS of sct-bkn AOA 5kft to 9kft will stick around sites
DLS/ALW through this evening, with CIGs rising at site PDT after
19Z. Winds will increase to 12-17kts with gusts to around 25kts at
sites PDT/RDM/ALW late this morning through the evening, becoming
light overnight. Winds at site DLS will be 15-20kts with gusts to
around 30kts through this evening, then becoming 12kts or less
overnight. Winds will otherwise be around 12kts or less through
the period at all other sites. Lawhorn/82


PREV DISCUSSION... /issued 435 PM PDT Thu Jun 26 2025/

.SHORT TERM...today through Sunday morning...Satellite shows
stratus entering from the WA Cascade and into the region. With a
shortwave passing through the PacNW, chances of PoP across the WA
Cascades increase through the afternoon and early evening hours.
Precip may extend close to the Yakima/Ellensburg area during the
late afternoon/early evening (>80% chance). Nothing to suggest any
thunder will be associated with these storms. Weather will clear
by the early morning hours of Friday with a ridge starting to push
through the area. Temperatures will slow rise through the short
term as the pattern begins to favor a warming trend from the short
term that will last through the long term. Winds will be breezy
across the Basin with general diurnal winds through the next few
days. Strongest winds will be today through Friday, with most
places capping their gusts at 20-30 knots.

.LONG TERM...Sunday morning through Thursday...The long term is
more animated than the short term, with a ridge setting up for a
potential heat wave during the holiday week coupled with
potential of thunderstorms in Central OR.

Ridging will start moving through the region over the weekend,
setting up a pattern for temperatures to begin a warming trend
over the weekend. High temperatures will tapper off in the mid 90s
for much of the Basin plus Central OR/Kittitas Valleys. Monday
appears to be the hottest day with NBM delivering triple digits
for the Columbia Basin and creeping into the Kittitas. NBM
currently advertises 40-60% chances of temperatures exceeding 100
degrees in the Tri-Cities area, among other portions of the WA
Columbia Basin. Heat advisories might need to be considered for
the Columbia Basin/Gorge as preliminary Heat Risk values are >3
for the Mon-Tues timeframe. Any advisories needed or added will be
assessed and decided through the next few days if they are still
warranted.

A break in the ridge with a shortwave will push down through the
region Monday, allowing for some moisture advection (coupled with
the daytime heating) to bring chances of thunderstorms across
Central OR and across large parts of the Blues. The highest chance
for thunderstorm development will be the early afternoon through
evening hours of Monday. Chances decrease vastly as we head into
Tuesday, with remnant showers lingering across the southern part
of the region. Things become a bit less confident heading into
Wednesday, as things naturally become less clear this far out.
Members are completely split Tuesday going into Wednesday onwards
how strong it will make the trough behind the ridge. Looking at
meteograms confirms that temperatures wildly fluctuate around
this same time frame.

&&

.PRELIMINARY POINT TEMPS/POPS...
PDT  56  85  56  92 /   0   0   0   0
ALW  59  83  59  90 /   0   0   0   0
PSC  57  87  56  93 /   0   0   0   0
YKM  52  85  55  92 /   0   0   0   0
HRI  56  87  56  94 /   0   0   0   0
ELN  54  82  55  91 /   0   0   0   0
RDM  44  83  46  90 /   0   0   0   0
LGD  49  80  52  88 /   0   0   0   0
GCD  48  82  51  91 /   0   0   0   0
DLS  57  85  59  94 /   0   0   0   0

&&

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

$$

SHORT TERM...95
LONG TERM....95
AVIATION...82