559
FXUS65 KPIH 251945
AFDPIH

Area Forecast Discussion
National Weather Service Pocatello ID
145 PM MDT Sat May 25 2024

.SHORT TERM...Today through Sunday Night.
Early afternoon satellite imagery shows a H5 trough working
through ERN Idaho which will continue to support isolated to
scattered showers and thunderstorms through this evening ahead of
drier conditions returning overnight tonight into Sunday. While
overall rainfall totals so far today have remained on the lighter
side, a weather station NE of Preston up towards Mink Creek
recorded 0.84" of rain in just an hour this morning which goes to
highlight the potential for heavy precipitation with more
organized convection. Stronger storms while staying very isolated
in nature today will support heavy rain, small hail, and wind
gusts up to around 30-40 mph.

As this H5 trough shifts east over the Continental Divide, we may
see some continued isolated showers in NE Idaho up around Island
Park and the Teton Valley but conditions will remain predominantly
dry going forward heading into Sunday to round out the weekend.
Drier, zonal flow will return for Sunday on the leading edge of a
H5 ridge that is expected to shift east over the NRN Rockies for
early next week. This will help to reintroduce a warming trend as
conditions remain dry with the warmest air mass of the season so
far looking to build into our region. Until then, highs this
weekend will be in the 50s/60s with lows in the 30s/40s.

Given elevated 700 mb winds aloft around 20-35 kts, a LAKE WIND
ADVISORY remains in effect until 9 PM for American Falls Reservoir
today with gusts up to 40 mph possible. An additional LAKE WIND
ADVISORY may be needed again on Sunday as winds look to be just
there again for a low-end issuance. Winds look to stay below WIND
ADVISORY issuance both today and tomorrow with the strongest
gusts around 25-45 mph, especially across the Snake Plain. MacKay

.LONG TERM...Memorial Day through next Saturday.
High pressure ridge aloft overhead with high pressure at the
surface will provide a beautiful Memorial Day with sunny skies and
highs in the 70s low elevations and upper 50s to lower 70s in the
mountains. Ridge moves east Tuesday with southwesterly flow aloft
bringing in much warmer air and almost all low elevation areas
will have high temperatures in the 80s and mainly 70s in the
mountains. With an slight increase in moisture there will be a
slight chance of showers and thunderstorms late in the day. The
main upper level trof will move through Wednesday with more
widespread showers and thunderstorms and much cooler conditions
moving in. A Canadian system passing to north will keep a slight
chance of convective activity Thursday and Friday in the Central
mountains and Upper Snake Highlands with dry conditions in the
snake river plain and southern mountains. Dry conditions are
expected next Saturday. High temperatures will be back down in the
60s and 70s Wednesday and all the way down to the 50s and 60s
Thursday as the Canadian system passes to north. It should rebound
nicely heading into the weekend with highs back to near normal
Saturday well into the 60s mountains and 70s valleys. Wednesday
and Thursday will be the windiest days as the upper level systems
drive through cold fronts and widespread 25 to 40 mph wind gusts
both days will occur. GK

&&

.AVIATION...For the 18Z TAFS through 18Z Sunday.
Upper level system working through eastern Idaho today and have
showers and thunderstorms at DIJ and IDA early this evening and
dry conditions at SUN and BYI as expect activity to be well east
of them. DIJ will dry out tonight with dry conditions expected
late tonight through Sunday at all sites with VFR conditions.
Breezy conditions with 10 to 20 knot sustained winds this evenings
at IDA, PIH and BYI and even SUN into early evening. The 10 to 15
knot speeds will likely continue overnight at BYI, PIH and IDA.
10 to 20 knots will continue at those sites Sunday. GK

&&

.PIH WATCHES/WARNINGS/ADVISORIES...
None.

&&

$$