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Area forecast discussion 
National Weather Service Spokane Washington
420 am PDT Wednesday Jul 30 2014

Synopsis...
sunny and hot weather will continue over the inland northwest
through at least Friday. A gradual increase in clouds over the
next few days may knock temperatures down a few degrees, but mid
90s to low 100s will be common through the work week. The threat
for thunderstorms should increase over the weekend which may
knock temperatures down a bit more.



&&

Discussion...
today through Thursday...the ridge of high pressure will remain
fixed over the region keeping temperatures well above normal. Dry
conditions will prevail for much of the forecast area but isolated
showers and thunderstorms will be possible for some of the higher
terrain today and Thursday. We did see a couple convective cells
pop up over the north Cascades Tuesday and since there will be a
bit stronger impulse brushing the area today, isolated ts were
added to the forecast there. The better (but still low) chance of
showers and thunderstorms will be across the southeast zones where
monsoonal moisture will push up from the south. Satellite imagery
at 2 am PDT shows this moisture headed our way and models are
showing a better, but still modest, surge for Thursday. Convective
parameters are not impressive but definitely Worth a slight chance
of thunder in the forecast. One question mark is the moisture from
the remnants of a tropical system that is streaming into socal but
models are keeping this well to our south around Nevada. The
increased cloud cover will work to keep daytime temperatures a
couple of degrees cooler than Tuesday, but not much more than
that. The heat will continue on Thursday with valley temps in the
mid 90s to low triple digits. Overnight lows will remain quite
warm, mainly in the 60s, with poor relative humidity recovery, especially for the
mid-slope locations. /Kelch

Thursday night through Tuesday...an Omega blocking pattern will be
over North America through Tuesday. Deep upper lows will be in the
eastern Pacific and another near Hudson Bay...with a mean ridge of
high pressure in between. The ridge axis is expected to move far
enough east over the next 24-36 hours for southwest flow to
develop across the Pacific northwest, this will allow moisture to
move up from the south and southwest. In addition there will be a
series of weak weather disturbances moving through the region.
While this flow pattern will result in a slight cool down in
temperatures, daily highs will remain 5-10 degrees above seasonal
averages. Moisture advection into the region will help to further
destabilize the atmosphere and in combination with the forcing
provided by the weak disturbances there will be a chance of late
day convection each day. This convection will be mainly tied to
the mountain terrain each afternoon, but in reality an afternoon
thunderstorm will be possible anywhere in the forecast area.
/Tobin

&&

Aviation...
12z tafs: scattered mid/high level clouds will continue to
overspread most sites through the period. Isolated showers and
thunderstorms may develop across the north Cascades and NE blue
mts into the Idaho Panhandle this afternoon but confidence is
very low that convection will affect any taf site. /Ek



&&

Preliminary point temps/pops...
Spokane 97 67 96 67 94 65 / 0 10 10 0 10 0
Coeur D'Alene 95 62 94 61 93 62 / 10 10 10 10 10 10
Pullman 95 56 94 59 92 57 / 10 10 10 10 10 20
Lewiston 102 70 101 71 99 68 / 10 10 10 10 20 20
Colville 102 57 101 58 97 59 / 10 10 10 10 10 10
Sandpoint 93 54 92 54 90 56 / 10 10 10 10 10 10
Kellogg 93 61 93 61 91 62 / 10 10 20 10 10 20
Moses Lake 102 64 101 64 99 64 / 10 0 0 10 10 10
Wenatchee 100 71 100 71 98 71 / 10 0 0 10 10 10
Omak 102 65 100 65 100 68 / 0 0 0 0 10 0

&&

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

$$

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