Scientific Forecaster Discussion

Return to Local Conditions & Forecast

Without Abbreviations
With Abbreviations

Area forecast discussion 
National Weather Service Spokane Washington
520 am PDT Tuesday Jul 28 2015

with the exit of the storm system that brought scattered showers
and thunderstorms to the area last evening a return to Summer
conditions will commence today. A dry and increasingly hot weather
pattern will persist through next weekend across the inland


today through tonight...
the synoptic pattern consists of a very potent upper low
currently in eastern Montana rapidly moving north and east. In its
wake, a zonal pattern is setting up over the Pacific northwest.
Water vapor imagery early this morning depicts a shortwave rapidly
moving into western Washington. The infrared is showing some
clouds associated with this feature as well...with some mid to
high level clouds being reported in southwestern British Columbia and western

Closer to home, the last showers rapidly moved out of our domain
overnight with mostly clear skies prevailing now. Temperatures
cooled into the 40s and 50s across the inland northwest under the
clear skies. Not seeing any observations indicating fog developed
but wouldn't be surprised to see some patches early this morning
in the northeastern valleys of Washington and north Idaho.

The aforementioned short wave moving west to east across the
region today is the only focus for potential clouds and light
precipitation. So far, no precip is being reported west of the
Cascades. Based on the higher resolution models indicating a few
showers from this feature, decided to bump up pops slightly along
the Canadian border. This feature quickly races to the east during
the day...exiting north Idaho by afternoon.

Behind this shortwave, any lingering mid and upper level clouds
will scatter out on our way to another mostly clear night. The
warming trend begins with temperatures rebounding to the upper 70s
to lower 80s today and continuing that trend overnight with
temperatures about 5 to 10 degrees warmer than this morning.
Localized gusty winds along the Cascade gaps but otherwise, winds
will be relatively light. /Ab

Wednesday through Monday...strong and consistent model agreement
exists for this period featuring a westerly flow aloft/Flat Ridge
scenario through next weekend. The storm track will lay well to
the north of the region and any seepage of monsoonal moisture from
the south will likely be shunted off to the east before deepening
enough to cause trouble anywhere but the farthest southeastern
margins of the forecast area late in the week. A stubborn surface
thermal trough will become established over the next few days in
the Columbia Basin. All of these elements argue strongly for a
return to deep Summer conditions across the forecast area with no
chance of precipitation except over the The Blues and Camas
Prairie area which may be brushed by the margin of any monsoonal

Expect a gradual increase in daytime highs and sultry overnight lows
as the week wears on...culminating with solid mid 90s at most
locations and a few triple digits in the lowest elevations Thursday
through Sunday at least. Relative humidities in the afternoons
will be very dry...but there are no significant wind issues
expected to cause any official red flag conditions. Way out on or
about Monday some of the model guidance depicts the approach of a
weak Pacific short wave. At this time this may create a slightly
better chance of thunderstorms next Monday but moisture
availability and model agreement on this scenario is too nebulous
to justify changing the current continued dry and hot forecast.


12z tafs: all mention of showers and fog have been removed in the
12z taf package. VFR conditions and diurnally driven winds expected
through Tuesday./Ab


Preliminary point temps/pops...
Spokane 79 56 87 62 93 65 / 0 0 0 0 0 0
Coeur D'Alene 78 52 87 57 92 58 / 0 0 0 0 0 0
Pullman 77 53 87 54 93 56 / 0 0 0 0 0 0
Lewiston 84 56 95 64 101 68 / 0 0 0 0 0 0
Colville 81 52 90 53 95 56 / 10 0 0 0 0 0
Sandpoint 76 49 84 49 89 50 / 10 0 0 0 0 0
Kellogg 76 49 85 55 91 56 / 0 0 0 0 0 0
Moses Lake 85 56 94 60 99 63 / 0 0 0 0 0 0
Wenatchee 85 56 95 66 99 68 / 0 0 0 0 0 0
Omak 85 52 94 58 98 60 / 10 0 0 0 0 0


Otx watches/warnings/advisories...


National Weather Service Glossary of Abbreviations