Alert archive / Idaho / Red Flag Warnings in 2021

Red Flag Warning 31, NWS Pocatello, ID

September 14, 20219 counties in Idaho

NWS Pocatello, ID issued this red flag warning at Sep 14, 2021, 1:28 PM MDT for 9 counties in Idaho. It took effect at Sep 15, 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
Sep 14, 2021, 1:28 PM MDT (19:28 UTC)
In effect from
Sep 15, 2021, 12:00 PM MDT
Expired
Sep 15, 2021, 9:00 PM MDT
In force
9 hr
Issued by
NWS Pocatello, ID

Counties Bingham County, ID, Bonneville County, ID, Butte County, ID, Clark County, ID, Fremont County, ID, Jefferson County, ID, Madison County, ID, Power County, ID, Teton County, ID

The radar

The Pocatello radar (KSFX), 77 km from the middle of the area, began a volume at 19:29 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

Riverton, WY (KRIW), launched 12:00Z, 7.5 hours before the alert went out and 307 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, Riverton, WY at 12:00Z on 2021-09-14Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 5 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Riverton, WY at 12:00Z on 2021-09-14The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 54 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
5 J/kg
Mixed-layer CIN
-215 J/kg
Mixed-layer LCL
1665 m above ground
0-6 km bulk shear
41 kt
0-1 km storm-relative helicity
54 m²/s²
0-3 km storm-relative helicity
127 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

252 
WWUS85 KPIH 141928
RFWPIH

URGENT - FIRE WEATHER MESSAGE
National Weather Service Pocatello ID
128 PM MDT Tue Sep 14 2021

...RED FLAG WARNING IN EFFECT FROM NOON TO 9 PM MDT WEDNESDAY FOR
GUSTY WINDS AND LOW RELATIVE HUMIDITY FOR IDAHO FIRE WEATHER ZONE
410...

IDZ410-151100-
/O.NEW.KPIH.FW.W.0031.210915T1800Z-210916T0300Z/
Upper Snake River Valley/Idaho Falls BLM-
128 PM MDT Tue Sep 14 2021

...RED FLAG WARNING IN EFFECT FROM NOON TO 9 PM MDT WEDNESDAY FOR
GUSTY WINDS AND LOW RELATIVE HUMIDITY FOR IDAHO FIRE WEATHER ZONE
410...

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 to 9 PM MDT Wednesday.

* AFFECTED AREA...Fire Weather Zone 410 Upper Snake River 
  Valley/Idaho Falls BLM.

* WINDS...Southwest 15 to 25 mph with gusts up to 35 mph.

* RELATIVE HUMIDITY...As low as 12 percent.

* IMPACTS...The combination of winds and low humidity may produce
  rapid spread of new or existing wildfires.

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
279 
WWUS85 KPIH 150950
RFWPIH

URGENT - FIRE WEATHER MESSAGE
National Weather Service Pocatello ID
350 AM MDT Wed Sep 15 2021

...RED FLAG WARNING REMAINS IN EFFECT FROM NOON TODAY TO 9 PM MDT
THIS EVENING FOR GUSTY WINDS AND LOW RELATIVE HUMIDITY FOR IDAHO 
FIRE WEATHER ZONE 410...

IDZ410-160300-
/O.CON.KPIH.FW.W.0031.210915T1800Z-210916T0300Z/
Upper Snake River Valley/Idaho Falls BLM-
350 AM MDT Wed Sep 15 2021

...RED FLAG WARNING REMAINS IN EFFECT FROM NOON TODAY TO 9 PM MDT
THIS EVENING FOR GUSTY WINDS AND LOW RELATIVE HUMIDITY FOR IDAHO
FIRE WEATHER ZONE 410...

* AFFECTED AREA...Fire Weather Zone 410 Upper Snake River 
  Valley/Idaho Falls BLM.

* WINDS...Southwest 15 to 25 mph with gusts up to 40 mph.

* RELATIVE HUMIDITY...As low as 12 percent.

* IMPACTS...The combination of winds and low humidity may 
  produce rapid spread of new or existing wildfires.

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.

&&

$$
367 
WWUS85 KPIH 160241
RFWPIH

URGENT - FIRE WEATHER MESSAGE
National Weather Service Pocatello ID
841 PM MDT Wed Sep 15 2021

...RED FLAG WARNING WILL EXPIRE AT 9 PM MDT THIS EVENING FOR
GUSTY WINDS AND LOW RELATIVE HUMIDITY FOR FIRE WEATHER ZONE 410...

IDZ410-160345-
/O.EXP.KPIH.FW.W.0031.000000T0000Z-210916T0300Z/
Upper Snake River Valley/Idaho Falls BLM-
841 PM MDT Wed Sep 15 2021

...RED FLAG WARNING WILL EXPIRE AT 9 PM MDT THIS EVENING FOR
GUSTY WINDS AND LOW RELATIVE HUMIDITY FOR FIRE WEATHER ZONE 410...

Winds continue to weaken this evening, along with relative
humidity slowly rising above 15 percent. Therefore, the warning
will expire as scheduled at 9 PM. Locally breezy conditions may
persist across the Snake Plain through the rest of the evening. 

$$

The office that day

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

IssuedProductOfficeCountiesLasted
Sep 14, 1:25 PM MDTWind AdvisoryPIHBingham, Bonneville, Butte, Jefferson32 hr

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.