Flash Flood Warning 7, NWS Pocatello, ID

134 
WGUS75 KPIH 230450
FFSPIH

Flash Flood Statement
National Weather Service Pocatello ID
1050 PM MDT Sat Aug 22 2026

IDC051-065-230500-
/O.EXP.KPIH.FF.W.0007.000000T0000Z-260823T0500Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Jefferson ID-Madison ID-
1050 PM MDT Sat Aug 22 2026

...FLASH FLOOD WARNING FOR THE BIG ROCK BURN SCAR WILL EXPIRE AT 11
PM MDT THIS EVENING FOR SOUTHEASTERN JEFFERSON AND SOUTH CENTRAL
MADISON COUNTIES...

The heavy rain has ended. Flooding is no longer expected to pose a
threat. Please continue to heed remaining road closures.

&&

LAT...LON 4366 11172 4367 11173 4368 11172 4366 11170
      4366 11167 4367 11165 4365 11163 4364 11164
      4364 11165 4363 11166 4363 11169 4364 11169
      4365 11171

$$

13

Area Forecast Discussion
National Weather Service Pocatello ID
411 PM MDT Sat Aug 22 2026

.KEY MESSAGES...

- Scattered thunderstorms return to all of southern Idaho.
  Thunderstorms continue through the next seven days for many
  locations in southern Idaho.

- Red Flag Warnings in place for scattered thunderstorms today
  for all of Central Idaho Dispatch area, Southern Idaho
  Dispatch area, and portions of the Eastern Idaho Dispatch
  area.

- After record heat the past two days, clouds and precipitation
  will cool afternoon highs significantly today, then continue a
  weak overall cooling trend through Friday.

&&

.DISCUSSION...
Issued at 124 PM MDT Sat Aug 22 2026

A ridge of high pressure over the southwest combined with an upper
low off the Pacific coast will support the flow of monsoon moisture
into Southeast Idaho over the next several days in southwest flow
aloft. Shower and thunderstorm coverage will become more widespread
again this afternoon and evening as an embedded shortwave works
through. The Storm Prediction Center has included almost the
entirety of the CWA in a Marginal Risk of severe weather today. The
storm environment becomes more favorable heading into the afternoon
through mid-evening hours, with models indicating 0-6km shear
increasing to 40 to 50 knots across portions of the CWA. The threat
of gusty winds increases as well, with RRFS DCAPE values ranging
around 1000 to 1400 J/kg. Thunderstorms will be capable of
outflows ranging 50 to 60 mph. Otherwise, moderate to heavy rain
will be possible with storms with models indicating
precipitable water ranging 0.70" to 1.4" today. Outside of
thunderstorms, winds will remain fairly weak today. Temperatures
today will run 5 to 10 degrees cooler than yesterday's record
temperatures.

The main upper level low pressure system will continue to track
northward into Canada throughout the day Sunday, resulting in less
widespread storm coverage on Sunday with activity more limited to
the higher terrain. On the other hand, winds will increase outside
of storms with gusts across the Snake River Plain, Arco Desert, and
portions of the central mountains ranging 30 to 40 mph. The
suppression of the ridge will mean a continuation of gradually
cooling temperatures through Monday before the ridge attempts to
rebound. During this time, temperatures will briefly warm by several
degrees, but ensembles show the next PacNW low reaching the coast
and flattening the ridge again come mid-week which will take our
temperatures back into seasonable territory or just below for the
latter half of next week. Southwest flow aloft will keep enough
monsoon moisture lifting northward to support daily chances of
showers and thunderstorms throughout next week.

&&

.AVIATION /00Z TAFS THROUGH 00Z SUNDAY/...
Issued at 411 PM MDT Sat Aug 22 2026

Another round of storms storms will move through this evening.
30 percent chance of storms on station at TAF locations. Gusty
outflow winds are the main aviation concern for this evening. A
few showers may drift through the region overnight, but no
significant impacts expected.

&&

.FIRE WEATHER...
Issued at 124 PM MDT Sat Aug 22 2026

We will continue with a RED FLAG WARNING for all
zones EXCEPT 413. There will be a mix of wet and dry thunderstorms,
with the main impact being storms potentially producing gusts 35-60
mph, if not a bit higher with some storms across the Snake Plain and
Magic Valley (410, 425). There is a 30-50% chance of wetting rains
across central and eastern Idaho through this evening. Morning cloud
cover had muddied the picture a bit on where higher coverage will
be, but not enough to make any changes to the warning layout. With
this monsoon push, we are expecting pockets of showers across our
area overnight, with a 10% chance or less of seeing an overnight
thunderstorm or two. As low pressure scoots northeast tomorrow, we
are expecting an increase in winds outside of any thunderstorms.
Gusts of 25-40 mph are expected across portions of the Snake Plain
(410), Lava Beds in the Magic Valley (425), the central mountains
(422, 475, 476), and along the Montana border in Zone 411. There is
some question on how much dry air works in across those areas. Right
now, the best chance of seeing much lower humidity is across the
central mountains.  We will likely see pockets of critical fire
weather conditions, but at the moment will hold off on any RED FLAG
WARNINGS for that combination. Elsewhere we are going to be
borderline for thunderstorm coverage across Zones 427 and 413. We
are also expecting similar issues, in addition to the overall wind,
across Zone 411. Again, with borderline conditions (coverage should
be much lower than today), we will not go with any warnings for
thunderstorms. Outflow gust potential for 35+ mph is lower tomorrow
(10-40%) vs today (40-90%). The chance of wetting rain is lower
overall 15-30% and more spotty as well. Expect more of the same on
Monday. The footprint for showers and storms increases, at least
based on current trends, but thunderstorm potential is still
borderline for more widespread coverage. Monsoon moisture looks to
stick around most of this week, potentially decreasing toward the
end of it. We will to watch trends over the next few days to see how
long it may be with us and how much precipitation we could see.

&&

.PIH WATCHES/WARNINGS/ADVISORIES...
Red Flag Warning until 9 PM MDT this evening for IDZ410-422-
425-427-475-476.

&&

DISCUSSION...Cropp
AVIATION...13
FIRE WEATHER...Keyes

Special Weather Statement
National Weather Service Pocatello ID
523 PM MDT Sat Aug 22 2026

IDZ051-052-054-055-230000-
Eastern Magic Valley ID-Arco/Mud Lake Desert ID-
Shoshone/Lava Beds ID-Lower Snake River Plain ID-
523 PM MDT Sat Aug 22 2026

...A STRONG THUNDERSTORM WITH GUSTS TO 55 MPH WILL IMPACT
SOUTHEASTERN BLAINE...SOUTH CENTRAL BUTTE...SOUTHEASTERN
LINCOLN...NORTHWESTERN POWER...WEST CENTRAL BINGHAM AND MINIDOKA
COUNTIES THROUGH 600 PM MDT...

At 522 PM MDT, Doppler radar was tracking a strong thunderstorm 16
miles north of Minidoka, or 23 miles northwest of Lake Walcott,
moving northeast at 35 mph.

HAZARD...Wind gusts of 50 to 55 mph.

SOURCE...Radar indicated.

IMPACT...Gusty winds could knock down tree limbs and blow around
         unsecured objects.

Locations impacted include...
Craters Of The Moon, Kimama, Laidlaw Corrals Airport, Bear Trap
Airport, and Coxs Well Airport.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

Torrential rainfall is also occurring with this storm and may lead to
localized flooding. Do not drive your vehicle through flooded
roadways.

&&

LAT...LON 4271 11364 4291 11400 4348 11346 4312 11285
TIME...MOT...LOC 2322Z 225DEG 29KT 4297 11360

MAX HAIL SIZE...0.00 IN
MAX WIND GUST...55 MPH

JKeyes

Special Weather Statement
National Weather Service Pocatello ID
538 PM MDT Sat Aug 22 2026

IDZ054>059-230030-
Eastern Magic Valley ID-Franklin/Eastern Oneida Region ID-
Marsh and Arbon Highlands ID-Raft River Region ID-
Southern Hills/Albion Mountains ID-Lower Snake River Plain ID-
538 PM MDT Sat Aug 22 2026

...STRONG THUNDERSTORMS WILL IMPACT SOUTHEASTERN BLAINE...WEST
CENTRAL ONEIDA...WESTERN POWER...SOUTHWESTERN BINGHAM...NORTHEASTERN
CASSIA AND SOUTHEASTERN MINIDOKA COUNTIES THROUGH 630 PM MDT...

At 537 PM MDT, Doppler radar was tracking an outflow boundary
extending from 13 miles northeast of Minidoka to Malta. Movement was
east at 35 mph.

HAZARD...Wind gusts of 50 to 55 mph.

SOURCE...Radar indicated.

IMPACT...Gusty winds could knock down tree limbs and blow around
         unsecured objects.

Locations impacted include...
American Falls, Malta, Neeley, Lake Walcott, western American Falls
Reservoir, Aberdeen, Declo, Rockland, Albion, Minidoka, Cold Water
Rest Area, Elba, Acequia, Yale Rest Area, Massacre Rocks, Pilar
Butte, Idahome, Sublett Reservoir, Interstate 84 And 86 Junction, and
Roy.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

&&

LAT...LON 4313 11286 4225 11266 4224 11363 4271 11363
TIME...MOT...LOC 2337Z 260DEG 29KT 4287 11329 4233 11334

MAX HAIL SIZE...0.00 IN
MAX WIND GUST...55 MPH

JKeyes

Special Weather Statement
National Weather Service Pocatello ID
559 PM MDT Sat Aug 22 2026

IDZ051>055-230045-
Eastern Magic Valley ID-Arco/Mud Lake Desert ID-
Upper Snake River Plain ID-Shoshone/Lava Beds ID-
Lower Snake River Plain ID-
559 PM MDT Sat Aug 22 2026

...OUTFLOW WINDS TO 55 MPH WILL IMPACT EAST CENTRAL BLAINE...
SOUTHEASTERN BUTTE...NORTHWESTERN POWER...WESTERN BONNEVILLE...
NORTHWESTERN BINGHAM AND NORTHEASTERN MINIDOKA COUNTIES THROUGH 645
PM MDT...

At 558 PM MDT, Doppler radar was tracking an outflow boundary
extending from 13 miles southeast of Craters Of The Moon to 17 miles
south of Southwest Inl to 17 miles northwest of Springfield to 9
miles northwest of Aberdeen. Movement was northeast at 45 mph.

HAZARD...Wind gusts of 50 to 55 mph.

SOURCE...Radar indicated.

IMPACT...Gusty winds could knock down tree limbs and blow around
         unsecured objects.

Locations impacted include...
Blackfoot, Atomic City, Rose, Central Inl, Southwest Inl, Taber,
Southeast Inl, Springfield, Rockford, Moreland, Pingree, Groveland,
East Butte, Big Southern Butte, Bear Trap Airport, Wapello, and Coxs
Well Airport.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

&&

LAT...LON 4363 11295 4360 11245 4353 11230 4319 11221
      4296 11320 4297 11342 4307 11353 4320 11355
TIME...MOT...LOC 2358Z 236DEG 41KT 4324 11335 4326 11315 4318 11301
4302 11298

MAX HAIL SIZE...0.00 IN
MAX WIND GUST...55 MPH

JKeyes

Special Weather Statement
National Weather Service Pocatello ID
638 PM MDT Sat Aug 22 2026

IDZ053-054-058-062-230130-
Upper Snake River Plain ID-Marsh and Arbon Highlands ID-
Blackfoot Mountains ID-Lower Snake River Plain ID-
638 PM MDT Sat Aug 22 2026

...STRONG THUNDERSTORMS WILL IMPACT NORTHWESTERN CARIBOU...NORTH
CENTRAL BANNOCK...NORTHEASTERN POWER...CENTRAL BONNEVILLE AND CENTRAL
BINGHAM COUNTIES THROUGH 730 PM MDT...

At 637 PM MDT, Doppler radar was tracking strong thunderstorms along
a line extending from near Moreland to near Fort Hall Bannock Creek
Lodge. Movement was northeast at 45 mph.

HAZARD...Wind gusts in excess of 45 mph.

SOURCE...Radar indicated.

IMPACT...Gusty winds could knock down tree limbs and blow around
         unsecured objects.

Locations impacted include...
Pocatello, Blackfoot, Chesterfield Reservoir, Goshen, Chubbuck,
Shelley, Firth, Fort Hall Buffalo Lodge, Rose, Fort Hall Eagle Lodge,
Fort Hall Lincoln Creek Lodge, Fort Hall Townsite, Moreland, Fort
Hall Mount Putnam, Fort Hall Putnam Lodge, Pocatello Airport,
Groveland, Basalt, Trail Creek Campground, and Wapello.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

&&

LAT...LON 4350 11179 4290 11189 4275 11262 4328 11248
TIME...MOT...LOC 0037Z 239DEG 41KT 4328 11243 4283 11257

MAX HAIL SIZE...0.00 IN
MAX WIND GUST...45 MPH

13

Special Weather Statement
National Weather Service Pocatello ID
700 PM MDT Sat Aug 22 2026

IDZ053-054-062>065-230145-
Big Hole Mountains ID-Upper Snake River Plain ID-Teton Valley ID-
Caribou Range ID-Blackfoot Mountains ID-Lower Snake River Plain ID-
700 PM MDT Sat Aug 22 2026

...STRONG THUNDERSTORMS WILL IMPACT WEST CENTRAL TETON...SOUTHEASTERN
JEFFERSON...NORTHERN BONNEVILLE...MADISON AND CENTRAL BINGHAM
COUNTIES THROUGH 745 PM MDT...

At 659 PM MDT, Doppler radar was tracking strong thunderstorms along
a line extending from Plano to near Lorenzo to near Ucon to near
Firth. Movement was east at 30 mph.

HAZARD...Wind gusts in excess of 45 mph.

SOURCE...Radar indicated and mesonet observations.

IMPACT...Gusty winds could knock down tree limbs and blow around
         unsecured objects.

Locations impacted include...
Idaho Falls, Rexburg, Rigby, Ririe Reservoir, Lorenzo, Aesmmon,
Shelley, Iona, Sugar City, Ucon, Menan, Ririe, Lewisville, Archer,
Green Canyon Hot Springs, Thornton, Heise, and Osgood.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Torrential rainfall is also occurring with these storms and may lead
to localized flooding. Do not drive your vehicle through flooded
roadways.

These storms may intensify, so be certain to monitor local radio
stations and available television stations for additional information
and possible warnings from the National Weather Service.

&&

LAT...LON 4388 11128 4373 11130 4337 11139 4338 11179
      4335 11227 4357 11210 4372 11202 4388 11197
TIME...MOT...LOC 0059Z 268DEG 26KT 4389 11190 4372 11191 4358 11200
4335 11221

MAX HAIL SIZE...0.00 IN
MAX WIND GUST...45 MPH

JKeyes

Special Weather Statement
National Weather Service Pocatello ID
755 PM MDT Sat Aug 22 2026

IDZ053-065-230230-
Upper Snake River Plain ID-Teton Valley ID-
755 PM MDT Sat Aug 22 2026

...A STRONG THUNDERSTORM WILL IMPACT SOUTH CENTRAL FREMONT...
SOUTHEASTERN JEFFERSON AND NORTHERN MADISON COUNTIES THROUGH 830 PM
MDT...

At 754 PM MDT, Doppler radar was tracking a strong thunderstorm near
Roberts, or 9 miles northwest of Rigby, moving northeast at 35 mph.

HAZARD...Wind gusts in excess of 45 mph.

SOURCE...Radar indicated.

IMPACT...Gusty winds could knock down tree limbs and blow around
         unsecured objects.

Locations impacted include...
Rexburg, Rigby, Lorenzo, Sugar City, Menan, Teton, Roberts,
Lewisville, Parker, Egin, St Anthony, Plano, Newdale, Thornton, and
Saint Anthony Sand Dunes.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

&&

LAT...LON 4363 11201 4379 11222 4407 11180 4387 11147
TIME...MOT...LOC 0154Z 232DEG 29KT 4377 11207

MAX HAIL SIZE...0.00 IN
MAX WIND GUST...45 MPH

13