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fxus66 kotx 181810 
afdotx

Area forecast discussion
National Weather Service Spokane Washington
1110 am PDT Wed Oct 18 2017

Synopsis...
a moist warm front will move into the region today and bring an
moderate precipitation to the region today and Thursday. A cold
front will follow on Friday for showers, gusty winds and cooler
temperatures that will last through the weekend and into Monday.
A return to warmer temperatures and drier conditions is expected
next week.



&&

Discussion...
a slow moving frontal system will spread bands of rain into
eastern Washington and north Idaho this afternoon. As of 11 am,
the majority of the warm sector precipitation with this frontal
system was over western Washington. A bit of light rain around
Walla Walla, Pullman, Lewiston, and Winchester developed around
mid morning and continues to bring trace amounts to far southeast
Washington into the Idaho Panhandle. This band is not being
handled particularly well by the morning model runs, but so far
the amounts seem to be minimal. Our better shot for rains region-
wide will develop between noon and 3pm as moisture is lifted over
the advancing warm front. This afternoon and early this evening,
we expect our most significant precipitation amounts to fall over
the mountainous zones...north and east of Spokane. Communities
like Kettle Falls, Northport, Priest Lake, and Sandpoint can
expect a tenth to a third of an inch by midnight with amounts up
to a half inch in the mountains. There may be a brief break in the
precipitation late tonight as warm frontal lifting translates
north of the Canadian border. Then early Thu morning, bands of
rain should increase again as the cold front slowly moves across
eastern Washington into north Idaho. Thu afternoon and evening
will bring the Palouse as well as the central and southern Idaho
Panhandle a good opportunity for a tenth to a third of an inch of
rain as the cold front hangs up over the Panhandle. /Gkoch

&&

Aviation...

18z tafs: the addition of low level wind shear to the Spokane and
Coeur D'Alene tafs is the biggest change to the latest forecast.
The NAM and GFS are in good agreement developing a 50kt jet at
850mb overnight ahead of a slow moving cold front. The core of
this low level jet is expected to set up from The Dalles to Moses
Lake to Spokane. Given the higher elevation of Spokane and cda, it
looks like the belt of strong winds will be within 2000 feet of
the surface. At this time, we did not include low level wind shear
at Moses Lake or Wenatchee since it the strongest shear may be
just above the 2000 feet criteria. Bands of rain will also
accompany this slow moving system. Warm frontal rains this
afternoon/evening and more rain with the cold front Thu morning.
/Gkoch



&&

Preliminary point temps/pops...
Spokane 54 48 53 42 51 36 / 90 80 90 90 50 20
Coeur D'Alene 55 46 55 41 49 36 / 90 80 80 90 50 30
Pullman 59 48 58 43 50 37 / 30 30 50 90 50 40
Lewiston 67 49 66 47 58 40 / 20 10 10 90 30 20
Colville 53 45 54 41 52 34 / 70 60 80 80 40 40
Sandpoint 51 44 52 38 48 33 / 100 100 100 100 70 40
Kellogg 53 43 56 40 45 35 / 70 60 40 100 80 70
Moses Lake 60 48 59 39 58 35 / 60 30 60 30 10 10
Wenatchee 56 45 58 41 55 37 / 30 10 50 40 10 20
Omak 54 42 58 36 56 32 / 40 40 80 40 30 10

&&

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

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