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Area forecast discussion 
National Weather Service Spokane Washington
232 PM PDT Sat Mar 28 2015

Synopsis...
showers will linger...but quickly end...over the Idaho Panhandle
very early in the evening. The gusty winds will also diminish
significantly. The weather Sunday and Monday should be mild and
relatively dry. Another fast moving front on Tuesday will bring
more showers and windy conditions. The pattern of unsettled
weather will continue through the work week.

&&

Discussion...
tonight and sunday: with the rapid exit east of the unstable short-
wave trough that helped to produce showers and very windy wx
across ern WA and north Idaho today, we'll shortly transition into
stable upper ridging overnight. The result will be dry wx,
decreasing winds, and possibly some valley fog. Just offshore is a
warm frontal boundary that will move quickly east through the
region by midday Sunday that will keep skies mostly cloudy for
most towns. As far as pcpn chances with this front, most model
guidance shows very light amnts of rain for mainly NE WA and north
Idaho coincident with the band of warm air advection/isentropic ascent. Pass
level snow is possible, but accumulations will be light, if any,
down to around 4500 ft. Confidence levels are low as far as a
patchy light rain reaching the lower elevations such as Spokane.
We have dry fcst attm. Bz

Sunday night through monday: as remnants of the previous system
continue to push out the region and a ridge pattern begins to
build, the higher terrain of the Cascades and Idaho Panhandle
could receive a rain shower. By Monday, the chance of precip is
near non existent and warm and drier is pushes temperatures a few
degrees higher than the previous days.

..strong winds expected Tuesday...

Beginning late Monday, early Tuesday, the ridge begins to
breakdown as a cold front begins to press into the region. This is
expected to bring rain showers for most populated locations in the
region. Snow levels will be above 4500 feet. A combination of the
cooler air aloft, orographic lift, and diurnal surface heating
could produce an isolated thunderstorm in southeastern Washington
and central Idaho region but the confidence is very low. The winds
behind the front will be strong. Sustained winds of 20 to 30 miles per hour
and gusts near 40 miles per hour are expected in the Columbia Basin.
Temperatures are expected to be near the season normals for this
time of year. /Jdc

Tuesday night through Saturday...westerly flow in the wake of the
departing cold front will give way to another upper level trough
that will bring another round of precipitation to the inland
northwest for Wednesday and Wednesday night. Windy conditions
behind the front will subside overnight. The cold pool aloft will
result in unstable conditions and a couple hundred j/kg of cape
will be available for the late afternoon and early evening hours
across the northern zones both Wednesday and Thursday but with
little in the way of a warm front ahead of the trough, it appears
that the atmosphere will be too cold for thunder but favorable for
graupel showers. There will be a very brief break in the unsettled
weather late Thursday or Friday as a transient ridge pops up
between the exiting trough and the next one in line to affect the
inland northwest. Models have yet come into agreement on the
timing of the ridge but with lingering instability and westerly
flow, the threat of isolated to scattered upslope showers will
remain for the rising terrain east of the basin. Cold air aloft
will Foster instability showers that could bring snow pellets down
to most valley floors. The Pacific trough that will affect the
region over the weekend will be deeper and colder than the mid
week system but timing is again in question. If we manage to get
partial clearing conditions during the overnight hours, there
remains the possibility of sub-freezing temperatures for all but
the lowest valleys but this is a low confidence forecast at this
time. /Kelch

&&

Aviation...
18z tafs: strong Post-frontal winds will impact the taf sites
through mid to late afternoon today. West winds sustained 20 to
25kts with gusts up to 35kts are expected with the highest gusts
at kgeg and kpuw. Rain over the Idaho Panhandle will continue to
decrease. A broken cumulus deck will likely bring a 2500 to 4000
deck back to Coeur D'Alene, Sandpoint, and possibly Spokane felts
by after 18-20z. Winds will diminish quickly with the setting
sun.Bz

&&

Preliminary point temps/pops...
Spokane 38 58 40 63 43 55 / 0 10 10 10 10 50
Coeur D'Alene 36 58 38 65 41 54 / 0 10 10 10 20 60
Pullman 38 58 41 65 44 52 / 0 10 10 10 30 60
Lewiston 40 64 43 69 46 56 / 0 0 0 0 20 50
Colville 37 60 40 64 41 57 / 0 10 10 10 20 50
Sandpoint 35 56 37 61 38 51 / 0 10 10 10 20 70
Kellogg 36 56 38 63 40 48 / 10 10 10 10 30 70
Moses Lake 39 65 40 68 43 60 / 0 10 0 0 10 20
Wenatchee 42 64 44 68 45 58 / 0 10 10 10 10 20
Omak 38 62 39 67 41 60 / 10 10 10 10 20 40

&&

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

$$

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