Alert archive / Idaho / Red Flag Warnings in 2021
Red Flag Warning 20, NWS Pocatello, ID
NWS Pocatello, ID issued this red flag warning at Jul 22, 2021, 2:00 AM MDT for 18 counties in Idaho. It took effect at Jul 22, 2021, 12:00 PM MDT. It was in force for 9 hr. 2 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 22, 2021, 2:00 AM MDT (08:00 UTC)
- In effect from
- Jul 22, 2021, 12:00 PM MDT
- Expired
- Jul 22, 2021, 9:00 PM MDT
- In force
- 9 hr
- Issued by
- NWS Pocatello, ID
Counties Bannock County, ID, Bear Lake 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, Lemhi County, ID, Madison County, ID, Oneida County, ID, Power County, ID, Teton County, ID, Twin Falls County, ID, Valley County, ID
The radar
The Pocatello radar (KSFX), 42 km from the middle of the area, began a volume at 08:04 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
| Time | Report | Where | Remark |
|---|---|---|---|
| Jul 22, 3:44 PM MDT | HEAVY RAIN 0.31 | 2 Wnw Downey, ID | 0.31 IN/10 MINUTES. FREQUENT LIGHTNING. PEA-SIZED HAIL. GUSTS TO 30 MPH. |
| Jul 22, 3:58 PM MDT | HAIL 0.25 | Lava Hot Springs, ID | PEA-SIZED HAIL. VERY HEAVY RAIN. STRONG WIND GUSTS. |
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, 8.0 hours before the alert went out and 270 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.
- Mixed-layer CAPE
- 4 J/kg
- Mixed-layer CIN
- -346 J/kg
- Mixed-layer LCL
- 3242 m above ground
- 0-6 km bulk shear
- 51 kt
- 0-1 km storm-relative helicity
- 4 m²/s²
- 0-3 km storm-relative helicity
- 158 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted.
327 WWUS85 KPIH 220800 RFWPIH URGENT - FIRE WEATHER MESSAGE National Weather Service Pocatello ID 200 AM MDT Thu Jul 22 2021 ...RED FLAG WARNING IN EFFECT FROM NOON TODAY TO 9 PM MDT THIS EVENING FOR GUSTY WINDS AND LOW RELATIVE HUMIDITY FOR FIRE WEATHER ZONES 475 AND 476... ...RED FLAG WARNING IN EFFECT FROM NOON TODAY TO 9 PM MDT THIS EVENING FOR SCATTERED THUNDERSTORMS FOR FIRE WEATHER ZONES 411, 413 AND 427... IDZ475-476-222100- /O.NEW.KPIH.FW.W.0020.210722T1800Z-210723T0300Z/ East Salmon River Mountains/Salmon NF- Lemhi and Lost River Range/Challis NF- 200 AM MDT Thu Jul 22 2021 ...RED FLAG WARNING IN EFFECT FROM NOON TODAY TO 9 PM MDT THIS EVENING FOR GUSTY WINDS AND LOW RELATIVE HUMIDITY FOR FIRE WEATHER ZONES 475 AND 476... The National Weather Service in Pocatello has issued a Red Flag Warning for gusty winds and low relative humidity, 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. * WINDS...Southwest 15 to 25 mph with gusts up to 35 mph. * RELATIVE HUMIDITY...10 to 18 percent. * THUNDERSTORMS...Isolated thunderstorms are expected, especially in Zone 476, with gusts over 35 mph possible. * IMPACTS...The combination of wind, low humidity and or lightning could create critical fire conditions. 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. && $$ IDZ411-413-427-222100- /O.NEW.KPIH.FW.W.0020.210722T1800Z-210723T0300Z/ Centennial Mountains and Snake River Range/Targhee NF- Caribou Range/Caribou NF- Goose Creek and Raft River Valley/Southern Sawtooth NF/Twin Falls BLM south of the Snake River- 200 AM MDT Thu Jul 22 2021 ...RED FLAG WARNING IN EFFECT FROM NOON TODAY TO 9 PM MDT THIS EVENING FOR SCATTERED THUNDERSTORMS FOR FIRE WEATHER ZONES 411, 413 AND 427... The National Weather Service in Pocatello has issued a Red Flag Warning for scattered thunderstorms, which is in effect from noon today to 9 PM MDT this evening. * AFFECTED AREA...Fire Weather Zone 411 Centennial Mountains and Snake River Range/Targhee NF, Fire Weather Zone 413 Caribou Range/Caribou NF and Fire Weather Zone 427 Goose Creek and Raft River Valley/Southern Sawtooth NF/Twin Falls BLM south of the Snake River. * IMPACTS...Lightning and or strong outflow winds could create critical fire conditions. * THUNDERSTORMS...Scattered thunderstorms are expected with a mix of wet and dry thunderstorms. Localized amounts over 0.25 inches are possible. * OUTFLOW WINDS...Winds over 35 mph are possible. PRECAUTIONARY/PREPAREDNESS ACTIONS... A red flag warning means that critical fire weather conditions are either occurring now, or will shortly based on these criteria for Southeastern Idaho: - Relative humidity at or below 15 percent and wind gusts of at least 25 mph in the mountains, or 30 mph in the Snake Plain. - Thunderstorm coverage of 25 percent, without specific rainfall criteria. - Other high impact events deemed critical by the National Weather Service and area fire management agencies. && $$
2 follow-up statements
306 WWUS85 KPIH 222046 RFWPIH URGENT - FIRE WEATHER MESSAGE National Weather Service Pocatello ID 246 PM MDT Thu Jul 22 2021 ...RED FLAG WARNING IN EFFECT FROM NOON TODAY TO 9 PM MDT THIS EVENING FOR GUSTY WINDS AND LOW RELATIVE HUMIDITY FOR FIRE WEATHER ZONES 475 AND 476... ...RED FLAG WARNING IN EFFECT FROM NOON TODAY TO 9 PM MDT THIS EVENING FOR SCATTERED THUNDERSTORMS FOR FIRE WEATHER ZONES 411, 413 AND 427... IDZ475-476-230300- /O.CON.KPIH.FW.W.0020.000000T0000Z-210723T0300Z/ East Salmon River Mountains/Salmon NF- Lemhi and Lost River Range/Challis NF- 246 PM MDT Thu Jul 22 2021 ...RED FLAG WARNING REMAINS IN EFFECT UNTIL 9 PM MDT THIS EVENING FOR GUSTY WINDS AND LOW RELATIVE HUMIDITY 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. * WINDS...Southwest 15 to 25 mph with gusts up to 35 mph. * RELATIVE HUMIDITY...10 to 18 percent. * THUNDERSTORMS...Isolated thunderstorms are expected, especially in Zone 476, with gusts over 35 mph possible. * IMPACTS...The combination of wind, low humidity and or lightning could create critical fire conditions. 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. && $$ IDZ411-413-427-230300- /O.CON.KPIH.FW.W.0020.000000T0000Z-210723T0300Z/ Centennial Mountains and Snake River Range/Targhee NF- Caribou Range/Caribou NF- Goose Creek and Raft River Valley/Southern Sawtooth NF/Twin Falls BLM south of the Snake River- 246 PM MDT Thu Jul 22 2021 ...RED FLAG WARNING REMAINS IN EFFECT UNTIL 9 PM MDT THIS EVENING FOR SCATTERED THUNDERSTORMS FOR FIRE WEATHER ZONES 411, 413 AND 427... * AFFECTED AREA...Fire Weather Zone 411 Centennial Mountains and Snake River Range/Targhee NF, Fire Weather Zone 413 Caribou Range/Caribou NF and Fire Weather Zone 427 Goose Creek and Raft River Valley/Southern Sawtooth NF/Twin Falls BLM south of the Snake River. * IMPACTS...Lightning and or strong outflow winds could create critical fire conditions. * THUNDERSTORMS...Scattered thunderstorms are expected with a mix of wet and dry thunderstorms. Localized amounts over 0.25 inches are possible. * OUTFLOW WINDS...Winds over 35 mph are possible. PRECAUTIONARY/PREPAREDNESS ACTIONS... A red flag warning means that critical fire weather conditions are either occurring now, or will shortly based on these criteria for Southeastern Idaho: - Relative humidity at or below 15 percent and wind gusts of at least 25 mph in the mountains, or 30 mph in the Snake Plain. - Thunderstorm coverage of 25 percent, without specific rainfall criteria. - Other high impact events deemed critical by the National Weather Service and area fire management agencies. && $$
018 WWUS85 KPIH 230251 RFWPIH URGENT - FIRE WEATHER MESSAGE National Weather Service Pocatello ID 851 PM MDT Thu Jul 22 2021 IDZ475-476-230400- /O.EXP.KPIH.FW.W.0020.000000T0000Z-210723T0300Z/ East Salmon River Mountains/Salmon NF- Lemhi and Lost River Range/Challis NF- 851 PM MDT Thu Jul 22 2021 ...RED FLAG WARNING WILL EXPIRE AT 9 PM MDT THIS EVENING FOR GUSTY WINDS AND LOW RELATIVE HUMIDITY FOR FIRE WEATHER ZONES 475 AND 476... Winds are weakening, and humidity is starting to recover across the area, so the Red Flag Warning will be allowed to expire at 9 PM MDT. $$ IDZ411-413-427-230400- /O.EXP.KPIH.FW.W.0020.000000T0000Z-210723T0300Z/ Centennial Mountains and Snake River Range/Targhee NF- Caribou Range/Caribou NF- Goose Creek and Raft River Valley/Southern Sawtooth NF/Twin Falls BLM south of the Snake River- 851 PM MDT Thu Jul 22 2021 ...RED FLAG WARNING WILL EXPIRE AT 9 PM MDT THIS EVENING FOR SCATTERED THUNDERSTORMS FOR FIRE WEATHER ZONES 411, 413 AND 427... Thunderstorm activity has mostly diminished and moved out of the area. Some isolated thunderstorms are still possible through midnight tonight. The Red Flag Warning will be allowed to expire at 9 PM MDT. $$
The office that day
Everything else NWS Pocatello, ID issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jul 21, 6:31 PM MDT | Special Weather Statement | PIH | Cassia | 59 min |
| Jul 21, 7:55 PM MDT | Special Weather Statement | PIH | Cassia | 50 min |
| Jul 21, 8:10 PM MDT | Special Weather Statement | PIH | Bingham | 65 min |
| Jul 21, 9:46 PM MDT | Special Weather Statement | PIH | Bingham, Power | 59 min |
| Jul 22, 10:36 AM MDT | Special Weather Statement | PIH | Power | 39 min |
| Jul 22, 1:46 PM MDT | Special Weather Statement | PIH | Oneida | 59 min |
| Jul 22, 2:37 PM MDT | Severe Thunderstorm Warning | PIH | Cassia, Oneida, Power | 38 min |
| Jul 22, 3:07 PM MDT | Special Weather Statement | PIH | Oneida | 38 min |
| Jul 22, 3:11 PM MDT | Special Weather Statement | PIH | Oneida | 34 min |
| Jul 22, 3:18 PM MDT | Special Weather Statement | PIH | Bonneville | 12 min |
| Jul 22, 3:24 PM MDT | Special Weather Statement | PIH | Cassia | 36 min |
| Jul 22, 3:39 PM MDT | Special Weather Statement | PIH | Bannock | 51 min |
| Jul 22, 3:50 PM MDT | Special Weather Statement | PIH | Oneida | 55 min |
| Jul 22, 4:09 PM MDT | Special Weather Statement | PIH | Power | 51 min |
| Jul 22, 4:45 PM MDT | Special Weather Statement | PIH | Oneida, Power | 60 min |
| Jul 22, 5:07 PM MDT | Special Weather Statement | PIH | Caribou | 53 min |
| Jul 22, 5:14 PM MDT | Special Weather Statement | PIH | Franklin | 46 min |
| Jul 22, 5:47 PM MDT | Special Weather Statement | PIH | Bear Lake, Caribou, Franklin | 88 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.