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Area forecast discussion 
National Weather Service Spokane Washington
523 am PDT Monday Jul 14 2014

Synopsis...
a low pressure system will bring clouds and thunderstorms to the
northern and eastern portions of the inland northwest today. This
will also bring cooler temperatures to the region. The heat will
return on Tuesday, with the hottest temperatures of the week on
Wednesday. A gradual cooling trend will then take place, resulting
in much cooler weather for the upcoming weekend.



&&

Discussion...
quick update to the forecast. Elevated convection is already
starting to fire over northeast Washington as well as in the
Cascades, earlier than anticipated. So the forecast has been
updated to reflect this. Rj

&&

Aviation...
12z tafs: complex forecast for many of the taf sites. As such,
confidence is low. An area of showers/thunderstorms in northeast
Oregon at 12z will affect the kpuw/klws taf sites this morning.
Meanwhile the remainder of the tafs should be VFR. During the
afternoon, thunderstorms will develop over the northern mountains,
and these could form as far south as the kgeg/ksff/kcoe forecast
area. Rj



&&

Previous discussion...

Synopsis...
a low pressure system will bring clouds and thunderstorms to the
northern and eastern portions of the inland northwest today. This
will also bring cooler temperatures to the region. The heat will
return on Tuesday, with the hottest temperatures of the week on
Wednesday. A gradual cooling trend will then take place, resulting
in much cooler weather for the upcoming weekend.
A low pressure system will bring clouds and thunderstorms to the
northern and eastern portions of the inland northwest today. This
will also bring cooler temperatures to the region. The heat will
return on Tuesday, with the hottest temperatures of the week on
Wednesday. A gradual cooling trend will then take place, resulting
in much cooler weather for the upcoming weekend.

Discussion...
today and tonight: radar and satellite show a wrapped up comma
head over western Washington, while the main lift is still going
on over northeast Oregon with elevated convection firing there all
night. Expect another vort Max to get wrapped into another comma
head somewhere near the Idaho/British Columbia border. Current water vapor imagery
shows a cusp developing over northeast Oregon as a new injection
of moisture comes in on the backside of the low. This cusp may be
the beginnings of the comma head. As this feature moves to the
northeast, we should see more shower activity move into southeast
Washington and the southern Panhandle this morning, and then over the
northeast in the afternoon/evening.

As this comma head sits and spins, it will bring widespread
showers and embedded thunderstorms to the northern/eastern
mountains. This activity could make it as far south as
Spokane/Ritzville area. Initially the dry atmosphere will
evaporate much of the precipitation, but eventually the atmosphere
will saturate and rain will reach the ground. Localized heavy rain
this evening is a definite possibility from Republic over to
northwest Montana.

Temperatures are tough to predict. Most of the region should see
another hot day with just a couple of degrees cooling. But the
clouds and showers over the northeast will result in about 10
degrees of cooling vs sunday's hot temperatures. Rj

Mon nt through next weekend: with the filling mid-level wave over
ern WA and north Idaho exiting southeast toward Wyoming Mon nt and tues, we
steadily decreased both the areal coverage and intensity of the
shower/thunder threat that will affect mainly north Idaho. The mid and
extended range fcst remains dry, though confidence is fairly high
that a dry fropa Fri will help to produce gusty W/NW winds (mainly
near the Cascade east slopes) both thurs and Fri. The GFS is the
most aggressive in bringing the upper trough and farther south,
potentially targeting NE WA and the north Idaho Panhandle with showers
mainly Fri. Again, winds will be the main issue. Another broad
upper trough will dig southeast down the British Columbia coast Sunday, but should not
pose a threat as far as pcpn. Expect well above normal high temps
mid-week (90s mostly) before cooling into the weekend. Bz

Aviation...
12z tafs: complex forecast for many of the taf sites. As such,
confidence is low. An area of showers/thunderstorms in northeast
Oregon at 12z will affect the kpuw/klws taf sites this morning.
Meanwhile the remainder of the tafs should be VFR. During the
afternoon, thunderstorms will develop over the northern mountains,
and these could form as far south as the kgeg/ksff/kcoe forecast
area. Rj

Fire weather...
the red flag warning for lightning in the Cascades will continue
through this morning and may need to be extended for the afternoon.
Today we should see the majority of the thunderstorm coverage over
northeast Washington and the northern Panhandle. Initially these
storms will be dry, but eventually they are expected to bring
wetting rains late this afternoon and this evening. Rj

&&

Preliminary point temps/pops...
Spokane 90 68 95 68 98 67 / 40 30 10 0 0 0
Coeur D'Alene 89 64 92 61 96 60 / 40 30 10 0 0 0
Pullman 91 59 94 57 97 56 / 30 20 10 0 0 0
Lewiston 99 71 101 69 104 68 / 30 10 10 0 0 0
Colville 91 59 99 59 101 58 / 50 40 0 0 0 0
Sandpoint 85 58 90 57 94 56 / 60 70 10 0 0 0
Kellogg 87 60 89 65 94 64 / 50 60 10 10 0 0
Moses Lake 100 68 104 66 105 65 / 20 10 0 0 0 0
Wenatchee 98 73 104 73 104 72 / 20 10 0 0 0 0
Omak 98 65 104 66 104 65 / 20 10 0 0 0 0

&&

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

$$

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