Scientific Forecaster Discussion

Return to Local Conditions & Forecast

Without Abbreviations
With Abbreviations

Area forecast discussion 
National Weather Service Spokane Washington
229 am PDT Tuesday Jul 29 2014

Synopsis...
hot temperatures and dry weather will continue through midweek.
Thunderstorms chances will increase during the latter portion of
the work week as monsoonal moisture overspreads the inland
northwest.



&&

Discussion...
today through Thursday...the ridge of high pressure will continue
to dominate the weather pattern across the region. Hot and dry
conditions will prevail with today likely to be the hottest day.
Triple digit temperatures will be common for valley locations. A
heat advisory remains in effect for the Lower Basin and portions
of the Washington Palouse and the Lewis-Clark Valley. Weak
disturbances will ride along the ridge Wednesday and Thursday and
if enough monsoonal moisture gets caught up in the flow we could
see showers and thunderstorms pop up across the southeast zones.
The NAM is the most generous developing quantitative precipitation forecast into the forecast
area. Both the GFS and ec are dry Wednesday but do bring precip
right up to our southern border for Thursday. For now the forecast
will continue with slight chance thunderstorms from the NE blue
mts into the central Panhandle mts. The increasing cloud cover
streaming up from the south will help to bring daytime
temperatures down a couple of degrees for Wednesday and Thursday
but will act to keep overnight temperatures quite warm. This will
be especially true for the mid-slopes where overnight relative humidity recovery
will be fair to poor. The one fortunate effect of this persistent
ridge is that winds will continue to be light and terrain driven.
/Kelch

Friday and saturday: this period has the potential to very active.
The models are indicating a disturbance associated with remnantsof
Tropical Storm Hernan moving through the region. The European model (ecmwf) has
been more consistent with bringing the disturbance through the
Pacific northwest than GFS. With that in mind, the forecast leans
toward the European model (ecmwf) which brings more of the moisture with the system
further west towards the central Columbia Basin. This led to an
increase in the pops and cloud cover for the period. Afternoon
convection will lead to possible thunderstorms and a few
hundredths of an inch of rain to the region. The heavier rainfall
will be in eastern Washington and the Idaho Panhandle. The Max
temperatures were lowered a couple of degrees to allow for the
increased cloud cover. Temperatures will still in the 90s for low
lying locations.

Sunday through tuesday: behind this system, a slight ridge pattern
will build in the Pacific northwest. This will lead to a drying
trend in the region and decreasing chances of precip for the
inland northwest. Temperatures will still be in the 90s for the
period. /Jdc



&&

Aviation...
06z tafs: high pressure will continue to keep generally clear
skies and light winds over the aviation area for the next
24 hours. /Pelatti



&&

Preliminary point temps/pops...
Spokane 99 68 96 67 95 69 / 0 0 0 10 10 10
Coeur D'Alene 98 64 94 62 94 64 / 0 0 10 10 10 10
Pullman 97 60 94 59 93 61 / 0 10 20 10 10 10
Lewiston 105 72 101 68 100 72 / 0 10 20 20 20 20
Colville 101 60 99 59 98 60 / 0 0 0 10 10 10
Sandpoint 94 57 91 56 93 56 / 0 0 10 10 10 10
Kellogg 94 62 91 60 92 63 / 0 0 10 20 10 10
Moses Lake 104 67 101 65 99 66 / 0 0 0 0 10 10
Wenatchee 102 71 100 70 99 71 / 0 0 0 0 10 10
Omak 103 66 102 65 100 66 / 0 0 0 0 10 10

&&

Otx watches/warnings/advisories...
Idaho...heat advisory until 8 PM PDT this evening for Lewiston area.

Washington...heat advisory until 8 PM PDT this evening for lower Garfield and
Asotin counties-Moses Lake area-upper Columbia Basin-
Washington Palouse.

&&

$$

National Weather Service Glossary of Abbreviations