882
FXUS66 KPDT 190926
AFDPDT

Area Forecast Discussion
National Weather Service Pendleton OR
226 AM PDT Wed Jun 19 2024

.SHORT TERM...Today through Friday...

 Bottom Line Up Front

1. Dry an warm conditions through the period.

There is not a whole lot to speak about in regards to the short
term. The upper level low that brought winds and rain to the region
has since moved eastwards and out of the region. Models show the
upper level flow has turned more to the northwest. Models also show
that there is a dry air mass moving in along with it. AS the upper
level flow continues to turn more zonal, winds will settle down and
conditions will dry out. Models do show a few shortwaves rippling
through the zonal flow, however, no precipitation will accompany
them.

Models show a surface level thermal trough moving in across the
region underneath the zonal flow by Thursday. The thermal trough
will bring with it warmer temperatures. EFI show temperatures today
will be near normal with over 75% of the raw ensembles having
temperatures in the upper 70s to low 80s for the Pendleton area and
central OR, mid to upper 80s for the Basins, Gorge and Kittitas and
Yakima Valleys and mid 60s to low 70s for the higher terrains.
Thursday over 65% of the raw ensembles have the Basins, central OR
as well as the Pendleton area in the upper 80s to low 90s and the
higher terrains in the mid to upper 70s. Friday will be the warmest
day of the short term with over 80% of the raw ensembles showing the
Pendleton area and central OR in the upper 80s to low 90s, the
Basins and adjacent valleys in the mid 90s and the higher terrains
in the upper 60s to mid 70s. Bennese/90

.LONG TERM...Saturday through Tuesday...

Upper level ridging will be over the area on Saturday, before
moving eastward as southwesterly flow increases ahead of an
approaching cold front and trough.

Saturday looks to be the hottest day of the extended period and
likely the hottest day of the summer so far.  High temperatures will
be well into the 90s, with locations in the Columbia Basin into the
upper 90s, and possibly making a run at 100 degrees.

Temperatures have been trending slightly higher, and the ECMWF is a
bit higher than the GFS.  For the Columbia Basin/Pasco...3 out of 30
(10%) of the GFS ensemble members are >=100 degrees on Saturday. The
ECMWF ensemble members are warmer, showing about 30/50 members (60%)
>=100 degrees on Saturday.  The NBM is in the middle with a roughly
30% chance of highs >= 100 degrees.

The ECMWF EFI does pick up some anomalies of 0.6 to 0.7 for high
temperatures both Saturday and Sunday, generally across east-central
and eastern Oregon, where normal highs would be lower.  Despite the
higher temperatures across the Columbia Basin on Saturday, anomalies
are lower as higher temperatures in that location are not as
anomalous in mid to late June.

Temperatures cool down on Sunday, as the ridge moves further east, a
cold front advances and the upper trough gets closer.  However,
temperatures will still remain above normal, general in the mid to
upper 80s to around 90 degrees.

There is also a chance of some showers in the Washington Cascades as
the front moves through later Sunday into Monday.  These showers
will be the only precipitation across the region through the
extended period, with much of the region remaining dry.

Additionally, as the front crosses the area, winds will increase and
become gusty, especially across the Columbia Basin, Gorge, Simcoe
Highlands, and Kittitas Valley.  Winds should gust generally in the
25 to 35 mph range, with some gusts as high as 40 mph, Sunday into
Sunday night.  Winds should begin to decrease on Monday.  NBM
probabilities of wind gusts >= 39 mph are 60 to 100 percent on
Sunday.  However, wind gusts probabilities decrease significantly at
higher values.  NBM probabilities of winds >= 47 mph are generally
30% or less except for a few spot locations and the Kittitas Valley.

High temperatures will further decrease on Monday and will mainly be
in the low to mid 80s.  Highs on Tuesday will be similar to
Wednesday.  These temperatures are fairly close to normal.

The deterministic models are in generally good agreement through the
period.  Some subtle differences appear around Monday/Tuesday. e
However, by Tuesday the ensemble cluster are fairly split as well
with each cluster having about 25% support of the ensembles.


&&

.AVIATION...12Z TAFS...High probability (100%) of VFR conditions
and winds 10 kts or less through the period.


&&

.PRELIMINARY POINT TEMPS/POPS...
PDT  82  50  87  54 /   0   0   0   0
ALW  85  52  91  57 /   0   0   0   0
PSC  87  55  92  58 /   0   0   0   0
YKM  83  53  89  56 /   0   0   0   0
HRI  88  53  93  56 /   0   0   0   0
ELN  82  50  87  54 /   0   0   0   0
RDM  81  46  84  50 /   0   0   0   0
LGD  77  47  84  52 /  10   0   0   0
GCD  80  48  86  51 /   0   0   0   0
DLS  88  58  92  61 /   0   0   0   0

&&

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

$$

SHORT TERM...90
LONG TERM....77
AVIATION...77