Alert archive / Idaho / Red Flag Warnings in 2021

Red Flag Warning 19, NWS Pocatello, ID

July 21, 20215 counties in Idaho

NWS Pocatello, ID issued this red flag warning at Jul 21, 2021, 1:15 AM MDT for 5 counties in Idaho. It took effect at Jul 21, 2021, 12:00 PM MDT. It was in force for 9 hr. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued
Jul 21, 2021, 1:15 AM MDT (07:15 UTC)
In effect from
Jul 21, 2021, 12:00 PM MDT
Expired
Jul 21, 2021, 9:00 PM MDT
In force
9 hr
Issued by
NWS Pocatello, ID

Counties Butte County, ID, Custer County, ID, Idaho County, ID, Lemhi County, ID, Valley County, ID

The radar

The Boise radar (KCBX), 194 km from the middle of the area, began a volume at 07:19 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.

The nearest sounding before it

Boise Airport, ID (KBOI), launched 00:00Z, 7.3 hours before the alert went out and 186 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 2021-07-21Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 2 joules per kilogram.LCLLFCEL10008507005003002001001 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 2021-07-21The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 7 square meters per square second.193958Sfc1 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
2 J/kg
Mixed-layer CIN
-225 J/kg
Mixed-layer LCL
2727 m above ground
0-6 km bulk shear
18 kt
0-1 km storm-relative helicity
7 m²/s²
0-3 km storm-relative helicity
-1 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

737 
WWUS85 KPIH 210715
RFWPIH

URGENT - FIRE WEATHER MESSAGE
National Weather Service Pocatello ID
115 AM MDT Wed Jul 21 2021

...RED FLAG WARNING IN EFFECT FROM NOON TODAY TO 9 PM MDT THIS
EVENING FOR SCATTERED THUNDERSTORMS FOR FIRE WEATHER ZONES
475 AND 476...

IDZ475-476-212100-
/O.NEW.KPIH.FW.W.0019.210721T1800Z-210722T0300Z/
East Salmon River Mountains/Salmon NF-
Lemhi and Lost River Range/Challis NF-
115 AM MDT Wed Jul 21 2021

...RED FLAG WARNING IN EFFECT FROM NOON TODAY TO 9 PM MDT THIS
EVENING FOR SCATTERED THUNDERSTORMS FOR FIRE WEATHER ZONES
475 AND 476...

The National Weather Service in Pocatello has issued a Red Flag
Warning for scattered thunderstorms, which is in effect from noon
today to 9 PM MDT this evening.

* AFFECTED AREA...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...Scattered thunderstorms will develop in the
  afternoon. Wetting rains are possible with some of the stronger
  storms, including localized rainfall amounts over 0.25 inches.

* OUTFLOW WINDS...Winds over 35 mph are possible. 

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.

&&

$$
2 follow-up statements
149 
WWUS85 KPIH 212025
RFWPIH

URGENT - FIRE WEATHER MESSAGE
National Weather Service Pocatello ID
225 PM MDT Wed Jul 21 2021

...RED FLAG WARNING IN EFFECT FROM NOON TODAY TO 9 PM MDT THIS
EVENING FOR SCATTERED THUNDERSTORMS FOR FIRE WEATHER ZONES
475 AND 476...

IDZ475-476-220300-
/O.CON.KPIH.FW.W.0019.000000T0000Z-210722T0300Z/
East Salmon River Mountains/Salmon NF-
Lemhi and Lost River Range/Challis NF-
225 PM MDT Wed Jul 21 2021

...RED FLAG WARNING REMAINS IN EFFECT UNTIL 9 PM MDT THIS EVENING
FOR SCATTERED THUNDERSTORMS FOR FIRE WEATHER ZONES 475 AND 476...

* AFFECTED AREA...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...Scattered thunderstorms will continue through
  the evening. Wetting rains are possible with some of the 
  stronger storms, including localized rainfall amounts over 0.25 
  inches.

* OUTFLOW WINDS...Winds over 35 mph are possible.

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.

&&

$$
619 
WWUS85 KPIH 220250
RFWPIH

URGENT - FIRE WEATHER MESSAGE
National Weather Service Pocatello ID
850 PM MDT Wed Jul 21 2021

IDZ475-476-220400-
/O.EXP.KPIH.FW.W.0019.000000T0000Z-210722T0300Z/
East Salmon River Mountains/Salmon NF-
Lemhi and Lost River Range/Challis NF-
850 PM MDT Wed Jul 21 2021

...RED FLAG WARNING WILL EXPIRE AT 9 PM MDT THIS EVENING FOR
SCATTERED THUNDERSTORMS FOR FIRE WEATHER ZONES 475 AND 476...

Thunderstorm coverage has decreased to isolated this evening, so
the warning will be allowed to expire. Isolated storms may
continue through midnight. 

$$

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 21, 3:23 PM MDTSpecial Weather StatementPIHCuster52 min
Jul 21, 3:40 PM MDTSpecial Weather StatementPIHBingham50 min
Jul 21, 3:43 PM MDTSpecial Weather StatementPIHCassia47 min
Jul 21, 4:20 PM MDTSpecial Weather StatementPIHMinidoka40 min
Jul 21, 4:36 PM MDTSpecial Weather StatementPIHPower39 min
Jul 21, 4:59 PM MDTSpecial Weather StatementPIHCassia46 min
Jul 21, 5:04 PM MDTSpecial Weather StatementPIHPower41 min
Jul 21, 5:14 PM MDTSpecial Weather StatementPIHCamas46 min
Jul 21, 5:19 PM MDTSpecial Weather StatementPIHPower56 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.