000
FXUS66 KOTX 131926
AFDOTX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SPOKANE WA
1226 PM PDT Mon May 13 2013

.SYNOPSIS...
A robust upper level disturbance will drag a cold front through
the region today and bring the first period of widespread
precipitation to the region in over three weeks. Look for locally
heavy downpours and thunderstorms as the front moves through the
region today. Behind the front expect temperatures near seasonal
norms with a chance of mountain showers and embedded
thunderstorms. The arrival of cooler, more seasonal temperatures
Tuesday through the upcoming weekend will allow many rivers to
recede.


&&

.DISCUSSION...
Update: The cold front is crossing the Cascade crest at noon
today. Numerous showers have developed ahead of the cold front and
these showers are expected to shift eastward with the front this
afternoon. A couple of strikes have already been observed in the
Northeast Mountains as mid level lapse rates steepen as colder
temps aloft move in with the upper level shortwave trough of lower
pressure. The main concern for thunderstorms will be across
southeast WA and across the central ID Panhandle. Daytime heating is
expected to increase surface based CAPE across these areas of up
around 500 J/KG. Strong 0-6 km shear with a negatively tilted
trough moving in onshore will give us a good set up for some
stronger storms to develop after 1:00 PM this afternoon. The HRRR
model has been consistent in developing these stronger cells over
the Blue Mountains in northeast Oregon. With a northeast steering
flow, these cells would push across the Northeast Mountains,
southeast WA Palouse, Camas Prairie and then continue northeastward
into the Central Panhandle Mountains. The main threat with these
cells will be the possibility for damaging winds and hail.

The upper level cold pool will nose its way across eastern WA
behind the front. We should begin to clear out behind the front,
which will allow for some thunderstorms to develop across the
basin and into the northern mountains of eastern WA through the
mid to late afternoon hours. These thunderstorms will likely
continue to flare up and move eastward into the early afternoon
hours. /SVH


&&

.AVIATION...
18Z TAFS: A cold front is beginning to push across the Cascade crest
late this morning. A line of showers are expected to develop along
this front and move eastward through the afternoon. Rain showers may
be heavy at times, mainly for the KGEG, KSFF, KCOE, KPUW and KLWS
taf sites. Heavy rainfall may reduce cigs and vis into MVFR category
as the front passes through. The best instability this afternoon
will be across far southeast WA and into the ID Panhandle. This area
is expected to see a better chance for stronger thunderstorms and
will be capable of frequent lightning strikes, gusty downdraft winds
and hail. The main taf sites that could be impacted by these
stronger thunderstorms will be KPUW and KLWS after 22Z this
afternoon. Thunderstorms will likely develop behind the cold front
this afternoon as well, which will continue into the evening hours.
Much of this thunderstorm activity will develop across the northern
mountains and could affect the Spokane/Coeur d`Alene areas by the
late afternoon hours. /SVH



&&

.PRELIMINARY POINT TEMPS/POPS...
Spokane        65  40  62  43  65  46 /  70  70   0   0  10  10
Coeur d`Alene  68  40  62  41  65  43 /  70  80   0   0  10  10
Pullman        69  40  61  39  65  43 /  60  80   0   0  10  10
Lewiston       79  44  70  45  74  50 /  60  70   0   0  10  10
Colville       73  39  67  39  70  42 /  90  70  10  10  20  20
Sandpoint      63  40  62  38  65  40 /  70  70  10   0  20  10
Kellogg        68  41  58  41  63  45 /  60 100  10   0  10  20
Moses Lake     71  44  70  45  74  47 /  60  10   0   0  10  10
Wenatchee      70  44  69  46  71  49 /  40  10   0   0  10  10
Omak           71  41  69  40  72  41 /  30  30   0  10  10  10

&&

.OTX WATCHES/WARNINGS/ADVISORIES...
ID...None.
WA...None.
&&

$$