Alert archive / Idaho / Red Flag Warnings in 2021

Red Flag Warning 18, NWS Pocatello, ID

July 19, 202125 counties in Idaho

NWS Pocatello, ID issued this red flag warning at Jul 19, 2021, 1:53 AM MDT for 25 counties in Idaho. It took effect at Jul 19, 2021, 12:00 PM MDT. It was in force for 33 hr. 9 reports came from inside the area while it was in force.

The area

The counties it named, with what was reported inside it.

The facts

Issued
Jul 19, 2021, 1:53 AM MDT (07:53 UTC)
In effect from
Jul 19, 2021, 12:00 PM MDT
Expired
Jul 20, 2021, 9:03 PM MDT
In force
33 hr
Issued by
NWS Pocatello, ID
All 25 counties

Bannock County, ID, Bear Lake County, ID, Bingham County, ID, Blaine County, ID, Boise County, ID, Bonneville County, ID, Butte County, ID, Caribou County, ID, Cassia County, ID, Clark County, ID, Custer County, ID, Franklin County, ID, Fremont County, ID, Idaho County, ID, Jefferson County, ID, Jerome County, ID, Lemhi County, ID, Lincoln County, ID, Madison County, ID, Minidoka County, ID, Oneida County, ID, Power County, ID, Teton County, ID, Twin Falls County, ID, Valley County, ID

The radar

The Pocatello radar (KSFX), 49 km from the middle of the area, began a volume at 07:56 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

What was reported inside it

TimeReportWhereRemark
Jul 20, 8:43 AM MDTHEAVY RAIN 0.475 Se Obsidian, IDMESONET STATION HPFI1 - HORTON PEAK. LAST 24 HOURS.
Jul 20, 8:50 AM MDTHEAVY RAIN 0.32 Wsw Custer, IDMESONET STATION YFFI1 - BONANZA. LAST 24 HOURS.
Jul 20, 9:15 AM MDTHEAVY RAIN 0.366 Sse Obsidian, IDMESONET STATION 3019 - SMILEY CREEK AIRPORT. LAST 24 HOURS.
Jul 20, 2:15 PM MDTTSTM WND GST 539 N Black Pine, IDITD RWIS STATION ITD47 - I-84 JUNIPER INTERCHANGE.
Jul 20, 4:14 PM MDTHAIL 0.253 W Grace, IDPEA-SIZED HAIL AND HEAVY RAIN (EST 0.60 IN IN 15 MIN).
Jul 20, 4:30 PM MDTHAIL 0.54 W Soda Springs, IDPUBLIC REPORTS HAIL ESTIMATED AT SLIGHTLY LARGER THAN PEAS AND VERY HEAVY RAIN WITH MINOR FLOODING ALONG US-30 BETWEEN ALEXANDER AND THE WESTERN SODA SPRINGS CITY LIMIT. TIME ESTIMATED BASED ON REPORT AND RADAR.
Jul 20, 4:42 PM MDTHEAVY RAIN 0.51 Wsw Soda Springs, IDHEAVY RAIN. APPROXIMATELY 0.50 IN 15 MIN.
Jul 20, 5:28 PM MDTHAIL 0.52 Nnw Tetonia, IDESTIMATED HALF-INCH HAIL COVERING THE ROAD. BETWEEN TETONIA AND FELT. TIME ESTIMATED BASED ON RADAR.
Jul 20, 5:49 PM MDTHEAVY RAIN 0.753 Ne Tetonia, IDHEAVY RAIN. ESTIMATING 0.75 IN IN 45 MIN.

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The nearest sounding before it

Boise Airport, ID (KBOI), launched 00:00Z, 7.9 hours before the alert went out and 250 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.

Skew-T log-pSkew-T log-p diagram, Boise Airport, ID at 00:00Z on 2021-07-19Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Boise Airport, ID at 00:00Z on 2021-07-19The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 7 square meters per square second.19395878Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.
Mixed-layer CAPE
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
4147 m above ground
0-6 km bulk shear
30 kt
0-1 km storm-relative helicity
7 m²/s²
0-3 km storm-relative helicity
69 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

092 
WWUS85 KPIH 190753
RFWPIH

URGENT - FIRE WEATHER MESSAGE
National Weather Service Pocatello ID
153 AM MDT Mon Jul 19 2021

...RED FLAG WARNING IN EFFECT FROM NOON TODAY TO 11 PM MDT TUESDAY
FOR THUNDERSTORMS FOR FIRE WEATHER ZONES 410, 411, 413, 422, 425,
427, 475 AND 476...

IDZ413-427-192100-
/O.UPG.KPIH.FW.A.0007.210719T1800Z-210720T0600Z/
/O.NEW.KPIH.FW.W.0018.210719T1800Z-210721T0500Z/
Caribou Range/Caribou NF-
Goose Creek and Raft River Valley/Southern Sawtooth NF/Twin Falls
BLM south of the Snake River-
153 AM MDT Mon Jul 19 2021

...RED FLAG WARNING IN EFFECT FROM NOON TODAY TO 11 PM MDT
TUESDAY FOR SCATTERED THUNDERSTORMS FOR FIRE WEATHER ZONES 413 
AND 427...

The National Weather Service in Pocatello has issued a Red Flag
Warning for scattered thunderstorms, which is in effect from noon
today to 11 PM MDT Tuesday. The Fire Weather Watch is no longer 
in effect.

* AFFECTED AREA...Fire Weather Zone 413 Caribou Range/Caribou NF 
  and Fire Weather Zone 427 Goose Creek and Raft River 
  Valley/Southern Sawtooth NF/Twin Falls BLM south of the Snake 
  River.

* IMPACTS...Lightning and or strong outflow winds could create 
  critical fire conditions.

* THUNDERSTORMS...Today, a mix of wet and dry scattered
  thunderstorms with some rainfall over one tenth of an inch
  possible. Isolated thunderstorms are expected overnight and
  Tuesday morning, before becoming scattered in the afternoon with
  increasing potential of heavier rainfall tomorrow. 
 
* OUTFLOW WINDS...Winds over 35 mph.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A red flag warning means that critical fire weather conditions
are either occurring now, or will shortly based on these criteria
for Southeastern Idaho:

- Relative humidity at or below 15 percent and wind gusts of at
least 25 mph in the mountains, or 30 mph in the Snake Plain.

- Thunderstorm coverage of 25 percent, without specific rainfall
criteria.

- Other high impact events deemed critical by the National
Weather Service and area fire management agencies.

&&

$$

IDZ411-192100-
/O.NEW.KPIH.FW.W.0018.210719T1800Z-210721T0500Z/
Centennial Mountains and Snake River Range/Targhee NF-
153 AM MDT Mon Jul 19 2021

...RED FLAG WARNING IN EFFECT FROM NOON TODAY TO 11 PM MDT
TUESDAY FOR SCATTERED THUNDERSTORMS FOR FIRE WEATHER ZONE 411...

The National Weather Service in Pocatello has issued a Red Flag
Warning for scattered thunderstorms, which is in effect from noon
today to 11 PM MDT Tuesday.

* AFFECTED AREA...Fire Weather Zone 411 Centennial Mountains and 
  Snake River Range/Targhee NF.

* IMPACTS...Lightning and or strong outflow winds could create 
  critical fire conditions.

* THUNDERSTORMS...Today, a mix of wet and dry scattered
  thunderstorms with some rainfall over one tenth of an inch
  possible. Isolated thunderstorms are expected overnight and
  Tuesday morning, before becoming scattered in the afternoon with
  increasing potential of heavier rainfall tomorrow. 
 
* OUTFLOW WINDS...Winds over 35 mph.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A red flag warning means that critical fire weather conditions
are either occurring now, or will shortly based on these criteria
for Southeastern Idaho:

- Relative humidity at or below 15 percent and wind gusts of at
least 25 mph in the mountains, or 30 mph in the Snake Plain.

- Thunderstorm coverage of 25 percent, without specific rainfall
criteria.

- Other high impact events deemed critical by the National
Weather Service and area fire management agencies.

&&

$$

IDZ410-422-425-475-476-192100-
/O.NEW.KPIH.FW.W.0018.210719T1800Z-210721T0500Z/
Upper Snake River Valley/Idaho Falls BLM-
Sawtooth Range/Northern Sawtooth NF-
Middle Snake River Valley/Twin Falls BLM north of the Snake River-
East Salmon River Mountains/Salmon NF-
Lemhi and Lost River Range/Challis NF-
153 AM MDT Mon Jul 19 2021

...RED FLAG WARNING IN EFFECT FROM NOON TODAY TO 11 PM MDT
TUESDAY FOR ISOLATED TO SCATTERED THUNDERSTORMS FOR FIRE WEATHER 
ZONES 410, 422, 425, 475 AND 476...

The National Weather Service in Pocatello has issued a Red Flag
Warning for isolated to scattered thunderstorms, which is in 
effect from noon today to 11 PM MDT Tuesday.

* AFFECTED AREA...Fire Weather Zone 410 Upper Snake River 
  Valley/Idaho Falls BLM, Fire Weather Zone 422 Sawtooth 
  Range/Northern Sawtooth NF, Fire Weather Zone 425 Middle Snake 
  River Valley/Twin Falls BLM north of the Snake River, Fire 
  Weather Zone 475 East Salmon River Mountains/Salmon NF and 
  Fire Weather Zone 476 Lemhi and Lost River Range/Challis NF.

* IMPACTS...Lightning and or strong outflow winds could create 
  critical fire conditions.

* THUNDERSTORMS...Today, a mix of wet and dry isolated
  thunderstorms with some rainfall over one tenth of an inch
  possible. Isolated thunderstorms are expected overnight and
  Tuesday morning, before becoming scattered in the afternoon with
  increasing potential of heavier rainfall tomorrow. 
 
* OUTFLOW WINDS...Winds over 35 mph.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A red flag warning means that critical fire weather conditions
are either occurring now, or will shortly based on these criteria
for Southeastern Idaho:

- Relative humidity at or below 15 percent and wind gusts of at
least 25 mph in the mountains, or 30 mph in the Snake Plain.

- Thunderstorm coverage of 25 percent, without specific rainfall
criteria.

- Other high impact events deemed critical by the National
Weather Service and area fire management agencies.

&&

$$
3 follow-up statements
048 
WWUS85 KPIH 192029
RFWPIH

URGENT - FIRE WEATHER MESSAGE
National Weather Service Pocatello ID
229 PM MDT Mon Jul 19 2021

...RED FLAG WARNING IN EFFECT THROUGH 11 PM MDT TUESDAY FOR 
THUNDERSTORMS FOR FIRE WEATHER ZONES 410, 411, 413, 422, 425, 427,
475 AND 476...

IDZ411-413-427-201200-
/O.CON.KPIH.FW.W.0018.000000T0000Z-210721T0500Z/
Centennial Mountains and Snake River Range/Targhee NF-
Caribou Range/Caribou NF-
Goose Creek and Raft River Valley/Southern Sawtooth NF/Twin Falls
BLM south of the Snake River-
229 PM MDT Mon Jul 19 2021

...RED FLAG WARNING REMAINS IN EFFECT UNTIL 11 PM MDT TUESDAY FOR
SCATTERED THUNDERSTORMS FOR FIRE WEATHER ZONE 411...

* AFFECTED AREA...Fire Weather Zone 411 Centennial Mountains and 
  Snake River Range/Targhee NF, Fire Weather Zone 413 Caribou 
  Range/Caribou NF and Fire Weather Zone 427 Goose Creek and 
  Raft River Valley/Southern Sawtooth NF/Twin Falls BLM south of 
  the Snake River.

* IMPACTS...Lightning and or strong outflow winds could create 
  critical fire conditions.

* THUNDERSTORMS...This evening, a mix of wet and dry scattered 
  thunderstorms with some rainfall over one tenth of an inch 
  possible. Isolated thunderstorms are expected overnight and 
  Tuesday morning, before becoming scattered in the afternoon with
  increasing potential of heavier rainfall tomorrow.

* OUTFLOW WINDS...Winds over 35 mph.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A red flag warning means that critical fire weather conditions
are either occurring now, or will shortly based on these criteria
for Southeastern Idaho:

- Relative humidity at or below 15 percent and wind gusts of at
least 25 mph in the mountains, or 30 mph in the Snake Plain.

- Thunderstorm coverage of 25 percent, without specific rainfall
criteria.

- Other high impact events deemed critical by the National
Weather Service and area fire management agencies.

&&

$$

IDZ410-422-425-475-476-201200-
/O.CON.KPIH.FW.W.0018.000000T0000Z-210721T0500Z/
Upper Snake River Valley/Idaho Falls BLM-
Sawtooth Range/Northern Sawtooth NF-
Middle Snake River Valley/Twin Falls BLM north of the Snake River-
East Salmon River Mountains/Salmon NF-
Lemhi and Lost River Range/Challis NF-
229 PM MDT Mon Jul 19 2021

...RED FLAG WARNING REMAINS IN EFFECT UNTIL 11 PM MDT TUESDAY FOR
ISOLATED TO SCATTERED THUNDERSTORMS FOR FIRE WEATHER ZONES 410,
422, 425, 475 AND 476...

* AFFECTED AREA...Fire Weather Zone 410 Upper Snake River 
  Valley/Idaho Falls BLM, Fire Weather Zone 422 Sawtooth 
  Range/Northern Sawtooth NF, Fire Weather Zone 425 Middle Snake 
  River Valley/Twin Falls BLM north of the Snake River, Fire 
  Weather Zone 475 East Salmon River Mountains/Salmon NF and 
  Fire Weather Zone 476 Lemhi and Lost River Range/Challis NF.

* IMPACTS...Lightning and or strong outflow winds could create 
  critical fire conditions.

* THUNDERSTORMS...A mix of wet and dry isolated thunderstorms 
  with some rainfall over one tenth of an inch possible. Isolated 
  thunderstorms are expected overnight and Tuesday morning, before
  becoming scattered in the afternoon with increasing potential 
  of heavier rainfall tomorrow.

* OUTFLOW WINDS...Winds over 35 mph.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A red flag warning means that critical fire weather conditions
are either occurring now, or will shortly based on these criteria
for Southeastern Idaho:

- Relative humidity at or below 15 percent and wind gusts of at
least 25 mph in the mountains, or 30 mph in the Snake Plain.

- Thunderstorm coverage of 25 percent, without specific rainfall
criteria.

- Other high impact events deemed critical by the National
Weather Service and area fire management agencies.

&&

$$
683 
WWUS85 KPIH 200706
RFWPIH

URGENT - FIRE WEATHER MESSAGE
National Weather Service Pocatello ID
106 AM MDT Tue Jul 20 2021

...RED FLAG WARNING IN EFFECT THROUGH 11 PM MDT THIS EVENING FOR 
THUNDERSTORMS FOR FIRE WEATHER ZONES 410, 411, 413, 422, 425, 427,
475 AND 476...

IDZ411-413-427-210500-
/O.CON.KPIH.FW.W.0018.000000T0000Z-210721T0500Z/
Centennial Mountains and Snake River Range/Targhee NF-
Caribou Range/Caribou NF-
Goose Creek and Raft River Valley/Southern Sawtooth NF/Twin Falls
BLM south of the Snake River-
106 AM MDT Tue Jul 20 2021

...RED FLAG WARNING REMAINS IN EFFECT UNTIL 11 PM MDT THIS
EVENING FOR ISOLATED TO SCATTERED THUNDERSTORMS FOR FIRE WEATHER 
ZONE 411, 413 AND 427...

* AFFECTED AREA...Fire Weather Zone 411 Centennial Mountains and 
  Snake River Range/Targhee NF, Fire Weather Zone 413 Caribou 
  Range/Caribou NF and Fire Weather Zone 427 Goose Creek and 
  Raft River Valley/Southern Sawtooth NF/Twin Falls BLM south of 
  the Snake River.

* IMPACTS...Lightning and or strong outflow winds could create 
  critical fire conditions.

* THUNDERSTORMS...Isolated thunderstorms are expected this
  morning, before becoming scattered this afternoon. Wetting rains
  are expected with most storms, along with the potential of
  localized flooding or debris flows. 

* OUTFLOW WINDS...Winds over 35 mph.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A red flag warning means that critical fire weather conditions
are either occurring now, or will shortly based on these criteria
for Southeastern Idaho:

- Relative humidity at or below 15 percent and wind gusts of at
least 25 mph in the mountains, or 30 mph in the Snake Plain.

- Thunderstorm coverage of 25 percent, without specific rainfall
criteria.

- Other high impact events deemed critical by the National
Weather Service and area fire management agencies.

&&

$$

IDZ410-422-425-475-476-210500-
/O.CON.KPIH.FW.W.0018.000000T0000Z-210721T0500Z/
Upper Snake River Valley/Idaho Falls BLM-
Sawtooth Range/Northern Sawtooth NF-
Middle Snake River Valley/Twin Falls BLM north of the Snake River-
East Salmon River Mountains/Salmon NF-
Lemhi and Lost River Range/Challis NF-
106 AM MDT Tue Jul 20 2021

...RED FLAG WARNING REMAINS IN EFFECT UNTIL 11 PM MDT THIS
EVENING FOR ISOLATED TO SCATTERED THUNDERSTORMS FOR FIRE WEATHER
ZONES 410, 422, 425, 475 AND 476...

* AFFECTED AREA...Fire Weather Zone 410 Upper Snake River 
  Valley/Idaho Falls BLM, Fire Weather Zone 422 Sawtooth 
  Range/Northern Sawtooth NF, Fire Weather Zone 425 Middle Snake 
  River Valley/Twin Falls BLM north of the Snake River, Fire 
  Weather Zone 475 East Salmon River Mountains/Salmon NF and 
  Fire Weather Zone 476 Lemhi and Lost River Range/Challis NF.

* IMPACTS...Lightning and or strong outflow winds could create 
  critical fire conditions.

* THUNDERSTORMS...Isolated thunderstorms are expected this
  morning, before becoming scattered this afternoon. Most storms
  will produce wetting rains, along with the potential for
  localized flooding or debris flows. Localized amounts over 0.50
  inches are possible in the central mountains.

* OUTFLOW WINDS...Winds over 35 mph.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A red flag warning means that critical fire weather conditions
are either occurring now, or will shortly based on these criteria
for Southeastern Idaho:

- Relative humidity at or below 15 percent and wind gusts of at
least 25 mph in the mountains, or 30 mph in the Snake Plain.

- Thunderstorm coverage of 25 percent, without specific rainfall
criteria.

- Other high impact events deemed critical by the National
Weather Service and area fire management agencies.

&&

$$
458 
WWUS85 KPIH 210303
RFWPIH

URGENT - FIRE WEATHER MESSAGE
National Weather Service Pocatello ID
903 PM MDT Tue Jul 20 2021


IDZ410-411-413-422-425-427-475-476-210415-
/O.CAN.KPIH.FW.W.0018.000000T0000Z-210721T0500Z/
Upper Snake River Valley/Idaho Falls BLM-
Centennial Mountains and Snake River Range/Targhee NF-
Caribou Range/Caribou NF-Sawtooth Range/Northern Sawtooth NF-
Middle Snake River Valley/Twin Falls BLM north of the Snake River-
Goose Creek and Raft River Valley/Southern Sawtooth NF/Twin Falls
BLM south of the Snake River-
East Salmon River Mountains/Salmon NF-
Lemhi and Lost River Range/Challis NF-
903 PM MDT Tue Jul 20 2021

...RED FLAG WARNING IS CANCELLED FOR SCATTERED THUNDERSTORMS FOR
FIRE WEATHER ZONES 410, 411, 413, 422, 425, 427, 475 AND 476...

The National Weather Service in Pocatello has cancelled the Red
Flag Warning.

Thunderstorm coverage has decreased to isolated, so we have
cancelled the Red Flag Warning.

$$

The office that day

Everything else NWS Pocatello, ID issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jul 19, 4:42 PM MDTSpecial Weather StatementPIHBear Lake63 min

Nearby

Red Flag Warnings in Idaho, 2021Every red flag warning in 2021

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.