102
FXUS66 KOTX 031808 CCA
AFDOTX

Area Forecast Discussion
National Weather Service Spokane WA
1108 AM PDT Fri May 3 2024

.SYNOPSIS...
The region will see mild and dry conditions today, with the
exception of a few scattered showers near the Canadian border. The
next system will move into the region Friday night, expanding
eastward through Saturday. Sunday will be cool and wet, with
additional unsettled weather expected early next week.

&&

.DISCUSSION...

Today through Saturday Night...As you wake up this morning and head
to work, you may notice that temperatures feel warmer than they have
the last few mornings. Well you`re not imagining things, the
temperatures are 5 to 10 degrees warmer at 2am than they were 24
hours ago. Clear skies this morning will see clouds increasing ahead
of the next system. There will be some isolated showers in far
northeastern Washington and ID Panhandle this afternoon, mainly
along the Canadian border. Winds will pick up along the lee side of
the Cascades, especially in the Okanogan Valley and Waterville
Plateau as the winds shift southerly with gusts of 35 to 40 mph.
Winds will decrease in the Okanogan Valley overnight but gusts of 30
mph remaining in the Waterville Plateau. Temperatures will rise
slightly, reaching the mid 60s with a few 70s in the LC Valley. Rain
will move in overnight over the Cascades, which will be the
beginning of a pattern change. Lows will be even warmer tonight but
closer to normal, only dropping into the 40s.

Saturday`s front will chug slowly eastward as the low slides towards
the Oregon coast. Morning temperatures will warm throughout the day,
with Saturday being the warmest of the forecast for locations along
and east of the Columbia Basin. Even with the additional cloud
cover, prefrontal warming will warm above the temperatures seen
today. The front will move through lee side of the Cascades in late
morning, keeping high temperatures in the 50s and rain showers
arriving earlier. Rain showers will continue to spread eastward
throughout the day. Breezy winds will continue through the day,
expanding into the upper Columbia Basin and Palouse with gusts to of
25 to 30 mph.  By late Saturday evening, much of the region will
have some sort of showers in their area. These showers will increase
throughout the night, bringing some beneficial rainfall to the
region. /KM

Sunday and Sunday night:  Wet and cool. As a closed upper low tracks
across Oregon into southern ID, a deformation band slowly pivots
across the Inland NW giving way to round of rain. Precipitable
waters increase to over 0.8 across eastern WA by Sunday morning.
- Precipitation: Moderate rain amounts of are expected especially
across parts of the Columbia Basin, southeast WA and the southern ID
Panhandle where the best dynamics and moisture will lie. Storm total
rainfall amounts are expected to rain from less than a tenth of an
inch in north-central WA to a half to near   an inch of rain across
southeast WA where stream flows are running low. Snow levels should
be high, spanning from 5-6 K ft with mainly the higher elevations
experiencing snow in the central Cascades, central ID Panhandle, and
Blue mountains. The precipitation will lead to small rises on area
rivers and streams although no flooding is expected yet any intense
rain rates may lead to ponding of water in low lying areas. Overall
anticipate the rain to be beneficial after the latest stretch of dry
weather.
-Temperatures: Daytime highs will be vary depending on where the
steady rain lies. Right now it will remain cooler from the eastern
Columbia Basin to the Spokane/ Coeur dAlene area and Palouse as
they struggle to reach 50, meanwhile temperatures will be nearing 60
in north central WA further from rain bands. Westerly winds
gradually increase by the afternoon to evening hours especially
across southeast WA in the lee of the Cascades with gusts 25 to  35
mph as the low level boundary shifts east and pushes across  north
ID by Sunday evening.

Monday through Tuesday:  Breezy and showery.  A west to northwest
flow aloft prevails in the wake of the departing low, while a
secondary weak trough rotates in from the Pacific. Low level
moisture remains and showers will be more numerous by Monday
afternoon as instability increases slightly. With mean capes near
100 J/kg across northeast WA into the ID Panhandle, this supports
the mention of thunderstorms for Monday afternoon and evening.
Breezy westerly winds continue with peak gusts in the afternoon
and evening hours of 25 to 30 mph especially across the Columbia
Basin and Palouse Monday afternoon. Slight chances anticipated for
Tuesday with mainly less moisture and less shower coverage. The
risk of thunderstorms will be less and confined over northeast WA.
Westerly winds continue although less gusty topping out at 20 to
25 mph. Anticipate more seasonal temperatures with highs in the
50s to lower 60s and overnight lows in the mid 30s to lower 40s.

Wednesday through Friday: Drier and warmer. An upper level ridge
builds over the eastern Pacific and builds inland. The threat of
showers lingers over north Idaho and brushing extreme eastern WA
for Wednesday, but trending less coverage for Thursday as drier
and more stable conditions arrive. Under lighter winds, the more
noticeable change will be warmer temperatures reaching the 60s to
lower 70s on Thursday and in the 70s by Friday. The dry and warm
pattern looks to continue into the following weekend. /rfox.

&&

.AVIATION...
18Z TAFS: Cumulus build ups and isolated showers over the mountains
of northeast Washington and in the Idaho Panhandle this afternoon. A
low pressure system will move slowly onshore off of the eastern
Pacific tonight. This will spread mid to high level clouds across
the region. Light rain is expect across the Cascades by the morning
hours on Saturday with rain at KEAT by 14-16Z. Ceilings down to 3-4
kft agl. with MVFR conditions possible. South and easterly winds
will pick up with the front approaching through the day today into
Saturday as well. KPUW and KCOE will see the potential for gusts of
15-25 kts overnight into Saturday morning with the easterly pressure
gradient tightening up.

FORECAST CONFIDENCE AND/OR ALTERNATE SCENARIOS: High confidence for
VFR conditions through Saturday afternoon except for at KEAT where
confidence is moderate. The HREF/NBM model guidance for KEAT
indicates a 30% chance ceilings lower down to between 2-3 kft agl.
and visibility down to 4-6 miles with rain by 15Z. /SVH

-----------------------

Confidence descriptors:
Low - Less than a 30 percent chance
Moderate - 30 to 70 percent chance
High - Greater than a 70 percent chance

For additional probabilistic information for NWS Spokane airports,
please refer to the Aviation Dashboard on our webpage:
https://www.weather.gov/otx/avndashboard

&&

.PRELIMINARY POINT TEMPS/POPS...
Spokane        65  45  68  42  48  40 /   0   0  10  40  80  70
Coeur d`Alene  65  42  67  42  47  40 /   0   0  10  30  60  80
Pullman        63  46  66  38  44  39 /   0   0  20  70  80  80
Lewiston       71  47  71  45  53  44 /   0   0  10  70  80  80
Colville       65  40  68  43  56  38 /  10   0  20  30  80  80
Sandpoint      62  42  65  46  51  41 /  10   0  10  30  60  90
Kellogg        62  43  65  44  46  40 /  10   0  10  40  80  90
Moses Lake     71  52  70  45  55  42 /   0  10  40  50  80  20
Wenatchee      68  52  60  47  58  44 /   0  20  70  50  40  10
Omak           70  49  68  49  63  42 /   0  10  30  40  40  30

&&

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

$$