Flash Flood Warning 4, NWS Pocatello, ID

623 
WGUS75 KPIH 240628
FFSPIH

Flash Flood Statement
National Weather Service Pocatello ID
1228 AM MDT Fri Jul 24 2026

IDC037-240638-
/O.EXP.KPIH.FF.W.0004.000000T0000Z-260724T0630Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Custer ID-
1228 AM MDT Fri Jul 24 2026

...FLASH FLOOD WARNING FOR THE WAPITI BURN SCAR WILL EXPIRE AT 1230
AM MDT EARLY THIS MORNING FOR WEST CENTRAL CUSTER COUNTY...

Flooding is no longer expected to pose a threat. Please continue to
heed remaining road closures.

&&

LAT...LON 4417 11511 4419 11512 4421 11517 4422 11516
      4422 11517 4424 11517 4425 11516 4429 11517
      4430 11518 4428 11520 4431 11522 4430 11524
      4432 11526 4440 11518 4435 11509 4440 11504
      4438 11501 4432 11504 4423 11497 4420 11498

$$

Cropp

Area Forecast Discussion
National Weather Service Pocatello ID
554 PM MDT Thu Jul 23 2026

.KEY MESSAGES...

- Surging Heat & Heat Advisory Friday: A building Four Corners
  ridge will push temperatures into the mid-to-upper 90s Friday
  through early next week. A Heat Advisory is in effect Friday
  for lower elevations—including the Snake Plain, Magic Valley,
  Arco Desert, Shoshone, and South Hills — where highs will
  reach 95°F to 100°F.

- Shift to Mixed Wet/Dry Storms: Drier air aloft will limit
  overall storm coverage today and Friday, favoring a mix of
  isolated wet and dry thunderstorms. Convection targets the
  Central Mountains and Continental Divide today before shifting
  toward the Utah border on Friday.

- Saturday Shortwave & Gusty Winds: A passing shortwave on
  Saturday will briefly elevate shower and thunderstorm chances
  while generating widespread wind gusts of 30 to 40 mph. This
  could lead to Red Flag Conditions for parts of eastern Idaho.

&&

.DISCUSSION...
Issued at 129 PM MDT Thu Jul 23 2026

Afternoon satellite imagery presents a stark contrast to 24
hours ago, showing mostly clear skies across eastern Idaho.
While gradual cumulus development is underway over the higher
terrain, lower elevations remain virtually cloud-free. Clear
skies coupled with an amplifying Four Corners ridge to our south
will allow significant heat to return to the region. While
afternoon highs today will remain near seasonal benchmarks in
the upper 80s to lower 90s across valley locations, temperatures
will quickly ramp up into the mid-to-upper 90s on Friday and
linger through the weekend into early next week. In response, a
Heat Advisory has been issued for Friday across lower-elevation
zones—including the Snake Plain, Magic Valley, Arco Desert,
Shoshone, and the South Hills—where widespread max temperatures
of 95°F to 100°F appear likely.

Regarding precipitation, an intrusion of drier mid-level air
will restrict overall storm coverage over the next 48 hours,
prompting a transition back to a mix of wet and dry
thunderstorms. High-resolution convective-allowing models (CAMs)
highlight the Central Mountains and the Continental Divide as
the primary focus for isolated afternoon development today.
Convective activity is forecast to shift southward toward the
Utah border on Friday.

A passing shortwave trough will interrupt the dry-leaning
pattern on Saturday, bringing an uptick in shower and
thunderstorm potential. In addition to storm chances, the
gradient will tighten, yielding widespread afternoon wind gusts
of 30 to 40 mph across the forecast area. Behind this
disturbance, the broad ridge will maintain its grip over the
Intermountain West, keeping temperatures consistently above
normal through early next week.

&&

.AVIATION /00Z TAFS THROUGH 00Z FRIDAY/...
Issued at 518 PM MDT Thu Jul 23 2026

There are much drier conditions today due to high pressure
directly over southeast Idaho. Expect VFR conditions at all TAF
sites through the period. There is about a 5 percent chance of
an isolated shower or storm around DIJ. So, have kept all
mention of convection OUT of the TAF. Winds will remain light
overnight. Skies will clear out overnight.

Tomorrow the high pressure ridging will move east of Idaho.
This will allow slightly breezy southerly winds for all TAF
sites. Expect cloudy conditions tomorrow afternoon into
tomorrow evening with monsoon moisture starting to move back
into the area. Isolated showers and thunderstorms are expected
generally in the mid to late afternoon for our southern TAF
sites. Have added VCSH and PROB30 for thunderstorms for PIH and
BYI for tomorrow afternoon. Look for convection for IDA and DIJ
in the early evening. &&

.FIRE WEATHER...
Issued at 129 PM MDT Thu Jul 23 2026

High pressure is building back in over the area today after
yesterday's shortwave and monsoon moisture push. A few isolated
thunderstorms will continue this afternoon, mainly being triggered
by orographic lift off our mountains and afternoon heating. Overall,
it will be a much drier day for most, but min RHs haven't completely
dropped from yesterday's moisture. That will be more noticeable
beginning tomorrow with min RHs areawide of 15 to 25 percent. Winds
will be a bit breezy on Friday afternoon, too, with gusts around 20
to 25 mph. We will see near-critical fire weather conditions in
parts of the Central Mountains in the afternoon, Fire Weather Zones
475 and 476. Winds get even more breezy on Saturday and another
round of monsoon moisture looks to impact parts FWZ 410, 411, 413,
and 427. So, Saturday looks like a day we may need Red Flag Warnings
for a mix of low RHs and gusty winds 475 and 476 and a mix of wet
and dry scattered thunderstorms in 410, 411, 413, and 427, but we
will see how the next few model runs look later tonight and
tomorrow. Overall, it doesn't look like the pattern is changing much
as we head into next week.

&&

.PIH WATCHES/WARNINGS/ADVISORIES...
Heat Advisory from 1 PM to 9 PM MDT Friday for IDZ051>057.

&&

DISCUSSION...McKaughan
AVIATION...TW
FIRE WEATHER...AMM

Special Weather Statement
National Weather Service Pocatello ID
952 PM MDT Thu Jul 23 2026

IDZ068-070>075-240415-
Challis/Pahsimeroi Valleys ID-Frank Church Wilderness ID-
Sawtooth/Stanley Basin ID-Wood River Foothills ID-
Big Lost Highlands/Copper Basin ID-Sun Valley Region ID-
Lost River Valleys ID-
952 PM MDT Thu Jul 23 2026

...STRONG THUNDERSTORMS WITH WIND GUSTS TO 45 MPH AND SMALL HAIL
WILL IMPACT SOUTH CENTRAL CUSTER... NORTHWESTERN BLAINE AND
SOUTHWESTERN BUTTE COUNTIES THROUGH 1015 PM MDT...

At 950 PM MDT, Doppler radar was tracking a cluster of strong
thunderstorms along a line extending from near Galena Lodge to 9
miles southwest of Ketchum to 9 miles southwest of Bellevue. Movement
was northeast at 45 mph.

HAZARD...Wind gusts in excess of 45 mph and pea size hail.

SOURCE...Radar indicated and mesonet observations.

IMPACT...Gusty winds could knock down tree limbs and blow around
         unsecured objects. Minor hail damage to outdoor objects is
         possible.

Locations impacted include...
Hailey, Ketchum, Sun Valley, Little Wood Reservoir, Bellevue, Trail
Creek Pass, Galena Lodge, Gannett, Galena Summit, Herd Lake, Garfield
Ranger Station, and Twin Bridges Airport.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

&&

LAT...LON 4433 11425 4397 11395 4354 11373 4323 11438
      4326 11437 4326 11439 4333 11440 4333 11444
      4355 11452 4376 11469 4381 11470 4381 11473
      4385 11477
TIME...MOT...LOC 0350Z 225DEG 39KT 4383 11469 4359 11449 4337 11439

MAX HAIL SIZE...0.25 IN
MAX WIND GUST...45 MPH

JKeyes