853
FXUS65 KPIH 190924
AFDPIH

Area Forecast Discussion
National Weather Service Pocatello ID
324 AM MDT Wed Jun 19 2024

.SHORT TERM...Today and Thursday
After a chilly start to the morning where most of the region
wakes up to temps in the 20s and 30s, temperatures will quickly
warm today as a warming trend begins in earnest. The frost
advisory continues into mid-morning but this should be the last of
the cold weather headlines we`ll see for awhile (in theory). This
will also coincide with an extended period of dry weather as not
much in the way of precipiation is expected over the week ahead.
Skies should be mostly clear to start the day for a good chunk of
the day today with daytime highs climbing into the 70s across the
valleys, 60s in the mountains. As we move into Thursday, temps
continue their upward climb by another 10+ degrees with 80s
becoming widespread in the valleys for Thursday which just happens
to be the first day of summer. Summer weather looks to remain in
place for awhile... McKaughan

.LONG TERM...Friday through next Wednesday
Under the increasing influence of high pressure through the
weekend, temperatures will continue to follow a warming trend with
afternoon highs back in the 80s/90s in the valleys starting
Friday. The warmest conditions are expected this weekend as a
broad H5 ridge axis shifts east over the NRN Rockies but ahead of
that, a H5 shortwave trough will work east on Friday across SRN
Idaho. 700 mb winds aloft will slightly increase which will
support winds around 15-25 mph with gusts between 20-40 mph in
addition to a 10-30% chance of showers and thunderstorms,
primarily in the mountains and across the Upper Snake Plain. The
SPC Day 3 Outlook highlights this well with general thunderstorms
across much of CNTRL/ERN Idaho with those chances less than 10% in
and around the ERN Magic Valley.

The warmest day of the forecast period continues to look like
Sunday with highs in the upper 80s to upper 90s, approaching
record levels across the Snake Plain and ERN Magic Valley. There
is currently around a 5-10% chance of exceeding 100 degrees across
the lower Snake Plain and ERN Magic Valley with warmest areas
expected to push into the upper 90s. For a comparison, here is a
look at the forecast high temperature on Sunday versus the record
high, in addition to the normal high for June 22nd for select
climate sites: Pocatello: 95/99/81, Idaho Falls: 94/95/79, and
Burley: 96/99/80. Stanley and Challis are currently about 4-7
degrees off from their respective records but this warmth will be
about 15 degrees above normal regionwide. As a result of this
seasonably warm weather, HeatRisk levels continue to trend up
towards the "Moderate" to "Major" categories with respect to
afternoon high temperatures this weekend with sufficient overnight
recovery expected courtesy of lows (albeit on the warmer side for
our region) in the 50s and 60s. A weak cold front will pass
through SRN Idaho on Monday associated with a passing system to
our north in WRN Canada, bringing highs back down to the low 80s
to low 90s.

Outside of a slight chance of isolated showers and thunderstorms on
Friday bringing with it little to no precipitation, conditions will
remain predominantly dry heading into next week. Ensemble clusters
and the EPS/GEFS models show a strong area of low pressure in the NE
Pacific this weekend which looks to gradually weaken and shift east
into early next week. As a result, the bulk of the moisture with
this system will end up staying north and west of our region as dry
conditions persist. This forecast is represented well in both the 6-
10 Day and 8-14 Day CPC Outlooks which show a 33-50% chance of below
normal precipitation across SRN Idaho. MacKay


&&

.AVIATION...For the 12Z TAFS through 12Z Thursday
Predominant VFR and dry conditions will continue through Thursday
with light winds and mostly clear skies throughout the day today.
Increasing mid-level clouds will then begin to build in tonight
into Thursday with CIGS generally around 12,000-25,000 feet.
MacKay

&&

.FIRE WEATHER...
After a chilly start across the area this morning, temperatures will
warm significantly through Wednesday with well above normal
temperatures expected later this week and into the weekend. This
will drive afternoon RHs into the teens and lower 20s for a good
portion of the week ahead. Not expecting much in the way of
precipitation through the next week but a few isolated showers and
thunderstorms will be possible on Friday across zones 475,476, 411
and 413 but not expecting much in the way of wetting rain. Winds
will generally be light into the weekend before breezier conditions
look to set in Sunday and into early next week. McKaughan

&&

.PIH WATCHES/WARNINGS/ADVISORIES...
Frost Advisory until 9 AM MDT this morning for IDZ051>054.

&&

$$