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Area forecast discussion 
National Weather Service Spokane Washington
229 PM PDT Thursday Jul 30 2015

Synopsis....
dry and hot weather will persist for the next several days. High
temperatures in the 90s to near 105 will be common through the
beginning of next week. A gradual cooling trend will take place by
mid week. A more dramatic change to the hot pattern is possible by
the middle of next week with an increasing threat of thunderstorms
each day from Monday through Thursday.

&&

Discussion...

Today through Friday....the slight amplification of the ridge over
the area allows hot and dry conditions to continue and peak Friday
with a number of locations heating up to and slightly over 100
degrees fahrenheit. A weak weather disturbance tightens the
pressure gradient across the Cascades up a bit late in the
afternoon Friday which will allow for some of The Gap winds to
increase and be gusty. This gusty wind along with the hot an dry
conditions warrants a highlight with a Fire Weather Watch which is
in effect for Friday afternoon and evening for parts of the fire
weather forecast area which includes the Wenatchee
area...Waterville Plateau....and the Kittitas and Yakima valleys.
/Pelatti

Friday night through sunday: upper level ridge remains in place
with very hot temperatures expected to continue through the
weekend. Daytime temps 10 to 12 degrees above average will be
seen...or widespread 90s in all the valleys with 100-105 across
portions of the Columbia Basin...Lewiston/Clarkston valley and
Wenatchee up along the Highway 97 corridor towards Entiat.
Overnight lows will be about 5 to 8 degrees above average. Skies
will remain mostly clear Friday and Saturday. By Sunday we start
to see more cloud cover as some moisture from the south creeps up
into the southern portions of Washington and the central Idaho Panhandle.

..unsettled weather expected Monday through Thursday...

Monday through thursday: Monday an upper level low pressure system
moves out of the Gulf of Alaska and towards British Columbia. This
will push our ridge axis east and open up the Pacific northwest to
south or southwesterly flow. Both the GFS and ec are showing
energy and associated moisture moving up from the Desert
Southwest. The models do not agree very well on specific timing,
but it looks as though we are entering a period of more unsettled
weather starting Monday and continuing on through most of the
week. The timing of these waves moving through is important,
because it could mean the difference in a widespread thunderstorm
or gust front outbreak verses some isolated thunderstorms moving
through. Models seem to agree on a Wednesday timeframe for a
potential cold front moving through for currently the best day of
potential widespread thunderstorms. For now the changes that have
been made are bringing the chance of thunderstorms just a bit
further west than previous forecast. Increased cloud cover given
the increase in moisture. Have kept temperatures very warm Monday
and Tuesday and then show a gradual cool down for Wed and thur
towards more seasonal averages. /Nisbet

&&

Aviation...
18z tafs: high pressure will continue to bring clear skies and
light terrain driven winds to the taf sites through 18z Friday.



&&

Preliminary point temps/pops...
Spokane 64 98 64 96 66 95 / 0 0 0 0 0 0
Coeur D'Alene 59 96 58 96 61 95 / 0 0 0 0 0 0
Pullman 57 98 56 96 58 95 / 0 0 0 0 0 0
Lewiston 68 105 69 104 69 103 / 0 0 0 0 0 0
Colville 57 100 57 98 59 97 / 0 0 0 0 0 0
Sandpoint 52 93 52 93 54 91 / 0 0 0 0 0 0
Kellogg 57 96 57 95 58 94 / 0 0 0 0 0 0
Moses Lake 62 102 63 101 66 100 / 0 0 0 0 0 0
Wenatchee 70 103 68 100 72 100 / 0 0 0 0 0 0
Omak 62 102 62 101 65 99 / 0 0 0 0 0 0

&&

Otx watches/warnings/advisories...
Idaho...none.
Washington...Fire Weather Watch from Friday afternoon through Friday evening
for East Washington central Cascade valleys (zone 677)-East
Washington northern Columbia Basin (zone 673)-East
Washington south central Cascade valleys (zone 676).

&&

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