585
FXUS65 KPIH 142003
AFDPIH

Area Forecast Discussion
National Weather Service Pocatello ID
203 PM MDT Mon Jul 14 2025

.KEY MESSAGES...

- Isolated showers and mainly dry thunderstorms, breezy winds, and
near critical to critical fire weather conditions today.

- Another round of isolated to scattered mainly dry thunderstorms
Tuesday and breezy winds Tuesday ahead of cold front late in the day.

- Cooler and drier Wednesday

- Warming trend to finish out the week.

&&

.SHORT TERM /THROUGH TUESDAY NIGHT/...
Issued at 203 PM MDT Mon Jul 14 2025

Satellite imagery shows weak feature just north of the Nevada border
allowing for shallow cumulus development and weak radar returns
south of the border. Further north, isolated thunderstorms have
developed from Copper Basin northeast toward the Divide. HREF
probabilities continue to support 70+% chance of greater than 35 mph
winds associated with the northern storms, including as they drift
into the northern portions of the Snake Plain. Gusty winds still
continuing to develop through the Arco Desert/Magic Valley/South
Hills along with dry surface conditions. Overall combination of the
above conditions contributing to critical fire conditions, so a Red
Flag Warning remains in place through 9 pm tonight. Should see winds
diminish and humidities rise above critical levels beyond that time.
High-res models hint at weak convection possibly continuing after
sunset, but confidence is low. Would not necessarily be surprised
with weak nocturnal convection late tonight into early Tuesday
morning across the south.

More organized system still forecast to work southeast across the
panhandle and western Montana during the day Tuesday. Precipitable
waters increase slightly into Tuesday, and coverage for
thunderstorms increases, especially across the eastern half of the
forecast area. Forecast soundings for Tuesday afternoon support
stronger outflows, with potential increasing for 50+ mph gusts,
especially across the south where SPC has included the region in a
Marginal Risk for severe. Outside of the storms, gusts could still
approach 25-35 mph, but humidities should be slightly higher
tomorrow. Additional Red Flag Warnings may be needed for
thunderstorm coverage, but not necessarily gusts and humidity.

&&

.LONG TERM /WEDNESDAY THROUGH SUNDAY/...
Issued at 203 PM MDT Mon Jul 14 2025

The mid/upper-level shortwave trough responsible for tomorrow`s
anticipated weather will continue to pull east away from the area on
Wednesday, leaving cooler, drier (in terms of
showers/thunderstorms), and lighter winds in its wake. Can`t rule
out an isolated shower or storm (10-20% chance) along the MT
Divide/Island Park area where a little moisture lingers beneath
cooler temps aloft, but precipitation potential appears minimal as a
whole. Will see a 5-8 degree cool down in the post-frontal airmass.
Ensemble means and ensemble clusters remain in good agreement
showing the upper flow backing to westerly by Thursday, allowing
temperatures to quickly rebound. West/southwest flow aloft then
persists into the weekend, leading to warm and predominantly dry
conditions. A few weak ripples embedded in the flow will support an
occasional isolated afternoon/evening thunderstorm chance (20% or
less) in the mountains, but again expecting most locations to remain
dry through this time. Seeing increased signals in ensemble clusters
today of a stronger shortwave trough arriving by late weekend/early
next week. This signal is showing up in roughly 60% of the cluster
membership on Sunday and in over 80% by Monday. While this may
briefly usher in slightly cooler air, unfortunately the bigger
impact will likely be a period of enhanced winds and resultant fire
weather concerns as moisture still appears lacking for any
appreciable precipitation threat.

&&

.AVIATION /18Z TAFS THROUGH 18Z TUESDAY/...
Issued at 1148 AM MDT Mon Jul 14 2025

Another weak disturbance passing through westerly flow aloft
will trigger isolated to scattered showers and thunderstorms
this afternoon and evening. KDIJ and KIDA will see the highest
probabilities of being impacted by any of these, and have
maintained PROB30 groups at both sites for a thunderstorm
mention and associated convective gusts around 30-35 kts.
Otherwise, VFR conditions are forecast through the period. Will
see west/southwest winds gust to around 20 kts this afternoon,
before diminishing after sunset this evening. Can`t rule out a
few lingering light showers primarily near KBYI overnight, but
not anticipating any real impacts from these. Another round of
showers and storms will develop tomorrow afternoon, this time
with greater areal coverage as a stronger shortwave and cold
front approach, with strong wind gusts remaining the main
concern with these storms.

&&

.FIRE WEATHER...
Issued at 203 PM MDT Mon Jul 14 2025

Isolated thunderstorms beginning to fire across the central
mountains from Copper Basin northeast to the Divide. High-resolution
model runs still largely support erratic outflow gusts from these
storms to exceed 35 mph from the western edge of Zone 476 across the
northern portion of Zone 410 to Zone 411 as the storms mature and
shift east through the afternoon and evening. The storms will be
mostly dry, but a stronger storm or two may be able to produce
amounts approaching one-tenth inch. Further south, wind gusts
outside of thunderstorm influence still expected to range 25-35 mph
across zones 425 and 427 this afternoon, encroaching into the Arco
Desert/INL portion of Zone 410. This region also expected to
continue to dry to afternoon humidity values below 15%. Thus Red
Flag Warnings remain in effect until 9pm for these regions, mainly
for gusty winds and low humidity, but also for the impact of the
thunderstorm outflows across the northern half of zone 410.

A more organized system is still expected to drop through the Idaho
panhandle and western Montana Tuesday. Moisture does look to
increase across the region, and thunderstorms should become more
scattered with the exception of 475, 422 and 425 where coverage
drops off significantly further west. Storms tomorrow will have the
potential to produce stronger wind gusts with potential for greater
than 50 mph especially 427 and 413. There is better potential for
wetting rains, but still not expected to be widespread with most
thunderstorms remaining fairly dry. Another Red Flag Warning
should be anticipated given the expected thunderstorm coverage
and potential strong outflows.

Cold front drops south through the region late in the day, with
temperatures slightly cooler Wednesday. A few thunderstorms remain
possible Wednesday mainly along the Yellowstone region, otherwise
dry conditions onset across the remainder of East Idaho. Westerly
flow allows temperatures to warm through the remainder of the week,
and weak passing shortwave features may produce isolated afternoon
thunderstorms now and then through the weekend along or north of the
Divide.


&&

.PIH WATCHES/WARNINGS/ADVISORIES...
Red Flag Warning until 9 PM MDT this evening for IDZ410-425-
427.

&&

$$

SHORT TERM...DMH
LONG TERM...KB
AVIATION...KB
FIRE WEATHER...DMH