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fxus66 kotx 242335 
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Area forecast discussion
National Weather Service Spokane Washington
435 PM PDT Mon Jul 24 2017

Synopsis...
the upcoming week will be quiet and warm, except for a slight
chance of mountain thunderstorms in Idaho Wednesday and Thursday
afternoon. Locally breezy conditions are possible each afternoon
and evening, especially near the Cascades.

&&

Discussion...
tonight through wednesday: a dry westerly flow will remain in
place through Tuesday night resulting in generally clear skies
except for a band of passing high clouds over northern Washington
and Idaho tonight. Winds will also be on the decline as well as
pressure gradients ease over the region. This is good news for
ongoing fires burning east of Sullivan Lake...near hunters...and
north of the Methow Valley in the Pasayten Wilderness. On
Wednesday the flow backs to the southwest allowing increased mid
level moisture to move in late in the afternoon over southeast Washington
ahead of a weak weather system over northern California. This
moisture combined with mid level instability could trigger an
isolated thunderstorms over the Blue Mountains or Camas Prairie.
850mb temperatures rise through the period from near 20c today to
24c Wednesday. This will allow for a warming trend with widespread
valley highs in the 90s for Wednesday. Jw

Wednesday night through monday: the extended period will likely
be a relatively quiet...dry and warm stretch of high Summer
weather over the region. As we have seen over the last month...a
Gulf of Alaska trough will dig and strengthen offshore providing
the region with increasingly southwesterly flow leading to another
round of above normal temperatures...but passing waves and minor
disturbances will moderate the warming trend with occasionally
breezy afternoon and evening conditions especially near the
Cascade gaps.

The only fly in the ointment is a stationary upper low...best
resolved on the water vapor satellite loop...which will eventually
eject inland and weaken as it is caught up in the southwest flow
ahead of the offshore Gulf of Alaska trough. Over the last few
days models have been having a bit of trouble handling this
evolution...with varying extent/areal coverage of minor threats of
mountain thunderstorms for the Wednesday/Thursday time period. At
this time it looks like some deeper moisture may fringe into the
Idaho Panhandle and extreme southeast Washington as the remnants
of this wave passes by. Thus a small chance of afternoon and
evening storms has been included in the forecast...but confidence
is quite low at this time of where if any thunderstorm activity
will be realized.

From Friday Onward the air mass looks too dry to support any
further thunder threats...and the main issue will be fire weather
related local breezy conditions with plenty of sunshine and
temperatures running 3 to 5 degrees above normal around the
region. /Fugazzi

&&

Aviation...
00z tafs: a dry west/northwest flow will dominate the weather
over the next 24hrs. This is expected to hold the main shower
threat south of the region, over Oregon and central and southern
Idaho, with some transient middle to high clouds and primarily
light winds. Some smoke from regional wildfires may occasional
drift around some airports but the main threat will be in the
northern valleys, north of the main taf sites. /J. Cote'

&&

Preliminary point temps/pops...
Spokane 59 89 61 93 65 91 / 0 0 0 0 0 0
Coeur D'Alene 54 89 55 91 58 91 / 0 0 0 0 0 10
Pullman 52 89 55 91 60 90 / 0 0 0 10 10 10
Lewiston 61 97 64 97 67 98 / 0 0 0 10 10 10
Colville 51 91 52 94 56 93 / 0 0 0 0 0 0
Sandpoint 46 88 48 90 52 90 / 0 0 0 0 10 10
Kellogg 51 86 53 88 57 88 / 0 0 0 0 10 10
Moses Lake 57 95 57 97 60 95 / 0 0 0 0 0 0
Wenatchee 63 92 67 94 67 93 / 0 0 0 0 0 0
Omak 61 94 61 97 61 96 / 0 0 0 0 0 0

&&

Otx watches/warnings/advisories...

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