Area Forecast Discussion Issued by NWS Spokane, WA
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FXUS66 KOTX 021135
AFDOTX
Area Forecast Discussion
National Weather Service Spokane WA
335 AM PST Tue Mar 2 2021
.SYNOPSIS...
A warming trend is then expected from mid to late week with dry
conditions Wednesday through Friday. By the weekend, temperatures
will cool back to seasonal normals along with an increasing threat
for showers and breezy conditions. Temperatures and snow levels
will drop further heading into next week with the possibility for
snow showers down in the valleys returning.
&&
.DISCUSSION...
Today through Wednesday night: Rather flat ridge over the area shows
a slight bit of warmer southwest to northeast reorientation as
ridging downstream amplifies. The end result is a warming trend
allowing for forecast temperatures on the warm side of climo. Some
of the high res models hint at some very spotty hit and miss
afternoon and evening convection generally confined to higher
terrain thus the forecast remains generally dry. This pattern may
allow for some overnight and early morning fog starting tonight.
/Pelatti
Thursday through Friday night: The Inland Northwest will be under
southwesterly flow with longwave troughing of lower pressure over
the eastern Pacific and ridging of high pressure over the
Rockies. Warmer temperatures being pumped northwards will result
in a continued warming trend into Friday. Moisture will be
advancing across the western portion of Washington State by
Thursday night into Friday with precipitation across the Cascades
possible. The added cloud cover there will result in noticeably
cooler temperatures over that portion of the region compared to
extreme eastern Washington and the Idaho Panhandle; Moses Lake to
Spokane, Coeur d`Alene to Kellogg, and Pullman to the Lewiston-
Clarkston Valley will be in the upper 50s to lower 60s for a high
on Friday.
Saturday through Tuesday: We will then see the upper level trough
offshore make a slow transition inland through the weekend into
early next week. A shortwave disturbance looks to push through
sometime Saturday afternoon into Sunday. There is uncertainty on
the timing of this wave and the associated frontal band looks to
get hung up over eastern Washington Saturday night. It looks as if
it will take a second shortwave with a bit more punch on Sunday to
actually drive the cold front across the region. Chances of
showers will increase with each of these shortwave disturbances.
Temperatures will be quite mild until we see the cold air move in
on Sunday. As such, showers will primarily bring rain to the
valleys and snow limited mainly to the mountains. Primary impacts
will be mainly at Sherman Pass and Stevens Pass (as snow levels
drop Sunday) where snow will be possible. Both passes don`t look
to get much snow, so potential impacts would likely be minor.
By early next week, we will see the trough in the eastern Pacific
nudge in over the Northwest. Temperatures will further drop back
to below normal for early March. Precipitation details are
uncertain this far out. It could be a fairly snow period if a
deformation axis sets up just right, or just be a bit unstable and
showery with mainly graupel showers. /SVH
&&
.AVIATION...
12Z TAFS: VFR conditions expected for the next 24 hours. Mid to
high level clouds will stream over Northeast WA and North ID from
time to time bringing a slight chance of light snow showers to
mountain locations. /Pelatti
&&
.PRELIMINARY POINT TEMPS/POPS...
Spokane 50 30 53 30 55 36 / 0 0 0 0 0 0
Coeur d`Alene 47 30 51 28 53 33 / 10 0 0 0 0 0
Pullman 47 30 51 31 54 36 / 0 0 0 0 0 0
Lewiston 55 33 56 33 57 37 / 0 0 0 0 0 0
Colville 49 29 50 28 53 33 / 0 0 0 0 0 0
Sandpoint 45 31 48 30 50 32 / 10 0 0 0 0 0
Kellogg 44 32 50 31 53 35 / 10 10 0 0 0 0
Moses Lake 56 30 56 32 57 38 / 0 0 0 0 0 0
Wenatchee 52 30 50 33 52 38 / 0 0 0 0 0 10
Omak 49 29 48 31 52 38 / 0 0 0 0 0 10
&&
.OTX WATCHES/WARNINGS/ADVISORIES...
ID...None.
WA...None.
&&
$$