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Area forecast discussion 
National Weather Service Spokane Washington
1051 am PDT sun Aug 30 2015

Synopsis...
a vigorous upper level disturbance will bring the inland
northwest some much needed rain today. Area wildfires will have a
good chance of a tenth to a quarter inch of rain. A cool,
occasionally breezy and showery weather pattern is expected much
of next week.



&&

Discussion...
morning forecast update: the 700 mb cold front is just now
beginning to cross east of the Cascade crest at 9:00 am this
morning. Low levels have moistened up considerably after
yesterday's cold front passage. This has resulted in a more
proficient rain producing front for this morning compared to
yesterday. Current radar shows a widespread coverage of showers
developing ahead of the front east of a line from Moses Lake to
Ritzville. Expect these showers to continue across the eastern half
of the forecast area through this morning. Best chances for
showers will be in the Panhandle for the afternoon as low levels
turn more westerly with orographic enhancement playing a bigger
role in shower development. Expect light to moderate rainfall with
these showers through the morning into the early afternoon.

Chances for thunderstorms will increase late this morning into the
early afternoon over the western basin up into the Okanogan
Valley/Highlands. Visible satellite imagery shows the cloud cover
dispersing a bit behind the frontal passage. This will result in
better surface heating that will combine with a relatively moist
boundary layer with dew points in the low to mid 50s. We will see
the possibility for thunderstorms increasing eastward through the
afternoon as the upper level trough pushes across the region.
Thunderstorms will be possible over the northern blue mtns,
Palouse, Spokane area and northeast mtns after about 1:00 PM PDT,
then push into the Panhandle by about 3:00 PM PDT this afternoon.

The convection will increase the wind potential. Winds will
generally be breezy with gusts to around 30 mph with today's cold
front passage. Thunderstorms that develop will be capable of
drawing down stronger gusts in the 40-50 mph range with the stronger
cells being capable to producing gusts closer to this upper range.
These stronger gusts are not expected to be widespread as
thunderstorm coverage will be isolated to scattered and the
stronger gusts will likely be confined to near the thunderstorms
themselves. Other potential impacts from thunderstorms today will
include small hail and heavy downpours. The good news with the
heavy rain aspect of the thunderstorms is that they are expected
to be moving at a good pace to the east. This should limit the
potential for any flash flooding with the risk looking low today.
However, burn scared areas may see some minor mud or debris flows
with thunderstorms. /Svh

&&

Aviation...
18z tafs: bands of rain will accompany the passage of a cold
front today. The most significant precipitation will occur over
the Idaho Panhandle between 18z-22z with ceilings occasionally
falling into the 2500-4000 ft range. There may also be some
scattered showers and isolated thunderstorms behind the cold
front. Sunshine will be necessary to destabilize the atmosphere
sufficiently for these cells. Only a handful of lightning
strikes are expected at this time. Breezy west to southwest winds
will follow the cold front passage in the 20z-02z time frame with
gusts to 20-30kts. /Gkoch



&&

Preliminary point temps/pops...
Spokane 66 50 71 53 72 53 / 50 10 20 10 10 20
Coeur D'Alene 63 48 70 51 72 51 / 80 20 20 10 10 20
Pullman 65 48 72 51 73 49 / 60 10 10 10 10 20
Lewiston 72 53 81 57 81 58 / 70 10 10 10 10 10
Colville 68 49 67 50 73 49 / 50 10 40 20 20 30
Sandpoint 61 47 66 49 71 49 / 90 30 40 20 20 30
Kellogg 60 45 69 48 70 49 / 90 30 20 10 10 40
Moses Lake 75 53 77 55 77 53 / 20 10 10 10 10 10
Wenatchee 74 53 74 55 74 56 / 10 10 20 20 10 20
Omak 74 50 70 51 74 50 / 20 10 30 30 20 20

&&

Otx watches/warnings/advisories...
Idaho...none.
Washington...none.
&&

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