Scientific Forecaster Discussion

Return to Local Conditions & Forecast

Without Abbreviations
With Abbreviations

Area forecast discussion 
National Weather Service Pendleton or
216 am PDT Monday Apr 27 2015

Short term...today through Wednesday...an upper level ridge will
move over eastern Washington and Oregon today. Temperatures will be
10-15 degrees warmer than yesterday due to subsidence from the
ridge. Warm temperatures will persist Tuesday except near the
Cascades. A cold front will move into the Cascades Tuesday
afternoon and across the rest of the area Tuesday night. This will
bring spotty showers and breezy winds. Models indicate marginal
instability for thunderstorms Tuesday evening with the frontal lift.
Confidence is too low to add to forecast yet...but I will tell the
day shift to look at this closely. Wednesday a broad trough will
keep southwest flow aloft over eastern Washington and Oregon.
However much cooler air behind the front will limit daytime heating
so the atmosphere will not be as unstable. The trough may trigger a
few mountain showers. Coonfield

Long term...Wednesday night through Sunday. After several days of
discrepancies in the synoptic pattern...medium range models are
finally in general agreement through Sunday by advertising a
westerly flow aloft through the period. The shortwave trough on
Wednesday will exit the region Wednesday night. Winds will diminish
Wednesday night...and showers will end overnight for most of the
area. A few lingering showers will remain along the Cascades. A
dry westerly flow will follow Thursday and Thursday night. The
slight chance probability of precipitation for the eastern mountains were removed and probability of precipitation
were decreased to slight chance for the east slopes of the Cascades
during this time. Future shifts may even decide to decrease or
remove probability of precipitation over the mountains for the Friday-sun forecast as well. Due
to previous model discrepancies...I decided to hold off on big
changes for days 5-7. Temperatures during the extended period will
be near seasonal average with highs in the middle 50s to upper 60s and
lows in 30s to middle 40s. Wister

&&

Aviation...12z tafs. VFR conditions and winds less than 10 knots
are expected for the next 24 hours. Skies will clear after
00z/28th.

&&

Preliminary point temps/pops...
PDT 70 45 72 43 / 0 0 10 20
alw 75 51 79 48 / 0 0 10 20
psc 76 44 81 47 / 0 0 10 20
ykm 74 45 75 41 / 0 0 10 10
hri 76 43 78 45 / 0 0 10 20
eln 73 42 72 41 / 0 0 10 10
rdm 77 39 69 32 / 0 0 10 20
lgd 69 41 76 43 / 0 0 10 20
gcd 76 41 82 43 / 0 0 10 20
dls 81 47 72 45 / 0 0 10 20

&&

PDT watches/warnings/advisories...
or...none.
Washington...none.
&&

For additional weather information, check our web site at...
www.Weather.Gov/Pendleton

$$

76/85/85

National Weather Service Glossary of Abbreviations