Area Forecast Discussion
Issued by NWS Pendleton, OR

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48
000
FXUS66 KPDT 282245 AAA
AFDPDT

Area Forecast Discussion...Update
National Weather Service Pendleton OR
345 PM PDT SAT MAY 28 2016

Updated for aviation discussion

.SHORT TERM...Tonight through Tuesday...W/NW flow is prevailing this
aftn as a shortwave trough exits far to the NE across the southern
Canadian prairies. A few showers are trying to move over the WA
Cascade crest...but only isolated/scattered showers will make it
past the immediate crest. The remainder of the area is experiencing
partly cloudy skies this aftn with temperatures in the lower
elevations warming to near/just below normal levels. Expect most
areas to remain dry tngt...with lows within a couple degrees of
normal.

Sunday/Sunday Night...A low amplitude trough...along with a mid level
shortwave...will cross the area Sunday. Deep layer moisture looks
quite limited for the lower elevations...but some moisture does pool
across the mtns...especially across NE Oregon in the aftn. Will use
scattered PoPs for the mtns...with dry conditions continuing for the
lower elevations. With GFS/NAM/ECMWF all depicting at least some
instability across far NE Oregon...will include tstms for the mtns
during the aftn/early evening. Strong/severe storms are not expected.
The surface pressure gradient tightens by evening...resulting in
breezy to windy conditions foe the Columbia Basin/Gorge as well as
the Kittitas Valley. Advisory level winds are not expected. The
gradual warming trend will continue...with high temperatures
slightly above normal. The trough axis will exit to the east Sunday
Night...with ridging building along the coast. Residual precip in
the evening will diminish by midnight. Near normal low temperatures
will prevail.

Monday/Tuesday...Ridging will continue to build across the
region...with the ridge axis across central/western Oregon by Tuesday
aftn. Dry/mostly clear conditions will prevail for all areas.
Slightly above normal temperatures Monday will warm to 5-10
degrees above normal for Tuesday...with widespread mid/upper 80s for
the Gorge/Basin.

.LONG TERM...Tuesday night through Friday night...High pressure will
continue over the interior pacific northwest keeping conditions
warm/hot and dry.  By Wednesday evening the ridge is expected to
shift further east and a more southerly flow will impact the area.
Increased mid level moisture with unstable conditions will allow for
possible thunderstorms...mainly Thursday and Friday. There is the
slight possibility along the east slopes of the Oregon Cascades on
Wednesday evening.  Right now these storms look to be focused over
the mountains with PWAT values near to below normal.  So expect that
these storms to be on the lower end of precipitation amounts.  Again
right now there is only a slight chance and we`ll have to monitor
the system as we approach the near term.  Additionally the current
forecast supports the GFS/Canadian Solution whereas the ECMWF
suggests dry and no thunderstorm.  So if the ECMWF pans out the
extended would be warm and dry.  Overall temperatures in the
extended are expected to be in the upper 80s to mid 90s for the
lower elevations and in the upper 70s to mid 80s mountains.

&&

.AVIATION...00Z TAFS..VFR conditions will persist at all TAF sites
for the next 24 hours. SCT to BKN high clouds mainly around 20-
25KFT. Winds will remain relatively light through 18z...AOB 12 KTs
through period at all terminals...except at KDLS where gusts up to
20 KTs will be possible mainly through 04z.  After 18z winds
expected to be mainly westerly 10-20kts. Weber

&&

.PRELIMINARY POINT TEMPS/POPS...
PDT  49  74  47  74 /   0  10  10   0
ALW  53  75  51  75 /   0  10  10   0
PSC  53  79  51  78 /   0  10   0   0
YKM  49  76  47  78 /   0  10   0   0
HRI  51  77  49  77 /   0  10   0   0
ELN  48  68  46  75 /  10  10  10   0
RDM  40  70  39  73 /   0  10   0   0
LGD  44  70  44  69 /   0  30  20   0
GCD  43  73  43  72 /   0  10  10   0
DLS  53  72  48  79 /   0  10  10   0

&&

.PDT Watches/Warnings/Advisories...
OR...None.
WA...None.
&&

$$

80/89/93



USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.