Alert archive / Idaho / Red Flag Warnings in 2021

Red Flag Warning 7, NWS Boise, ID

July 4, 202110 counties in Idaho

NWS Boise, ID issued this red flag warning at Jul 4, 2021, 8:10 AM MDT for 10 counties in Idaho. It took effect at Jul 4, 2021, 12:00 PM MDT. It was in force for 11 hr. 21 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 4, 2021, 8:10 AM MDT (14:10 UTC)
In effect from
Jul 4, 2021, 12:00 PM MDT
Expired
Jul 4, 2021, 11:00 PM MDT
In force
11 hr
Issued by
NWS Boise, ID

Counties Boise County, ID, Camas County, ID, Elmore County, ID, Gem County, ID, Gooding County, ID, Jerome County, ID, Lincoln County, ID, Owyhee County, ID, Twin Falls County, ID, Valley County, ID

The radar

The Boise radar (KCBX), 86 km from the middle of the area, began a volume at 14:14 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 4, 5:31 PM MDTTSTM WND GST 5313 Ssw Riddle, IDMESONET STATION SPAI1 SHO-PAI.
Jul 4, 5:31 PM MDTNON-TSTM WND GST 5313 Ssw Riddle, IDMESONET STATION SPAI1 SHO-PAI.
Jul 4, 6:52 PM MDTTSTM WND GST 4920 Wsw Castleford, IDMESONET STATION HBFI1 HORSE BUTTE.
Jul 4, 6:52 PM MDTNON-TSTM WND GST 4920 Wsw Castleford, IDMESONET STATION HBFI1 HORSE BUTTE.
Jul 4, 7:02 PM MDTTSTM WND GST 597 Se Hot Springs, IDMESONET STATION TT087 SAYLOR CREEK.
Jul 4, 7:02 PM MDTNON-TSTM WND GST 597 Se Hot Springs, IDMESONET STATION TT087 SAYLOR CREEK.
Jul 4, 7:05 PM MDTTSTM WND GST 481 S Mountain Home Afb, IDAWOS STATION KMUO MOUNTAIN HOME AFB.
Jul 4, 7:05 PM MDTNON-TSTM WND GST 481 S Mountain Home Afb, IDAWOS STATION KMUO MOUNTAIN HOME AFB.
Jul 4, 7:24 PM MDTTSTM WND GST 566 S Twin Falls, IDASOS STATION KTWF TWIN FALLS.
Jul 4, 7:24 PM MDTNON-TSTM WND GST 566 S Twin Falls, IDASOS STATION KTWF TWIN FALLS.
Jul 4, 7:25 PM MDTTSTM WND GST 488 Wnw Mountain Home Afb, IDMESONET STATION TS962 7 WNW MOUNTAIN HOME AFB.
Jul 4, 7:25 PM MDTNON-TSTM WND GST 488 Wnw Mountain Home Afb, IDMESONET STATION TS962 7 WNW MOUNTAIN HOME AFB.
Jul 4, 7:35 PM MDTTSTM WND GST 473 E Jerome, IDAWOS STATION KJER JEROME COUNTY.
Jul 4, 7:35 PM MDTNON-TSTM WND GST 473 E Jerome, IDAWOS STATION KJER JEROME COUNTY.
Jul 4, 7:40 PM MDTTSTM WND DMG6 Sw Wendell, IDREPORT FROM MPING: 1-INCH TREE LIMBS BROKEN; SHINGLES BLOWN OFF.
Jul 4, 7:44 PM MDTTSTM WND GST 5010 Ssw Hill City, IDMESONET STATION DEHI1 DEER HAVEN.
Jul 4, 7:44 PM MDTNON-TSTM WND GST 5010 Ssw Hill City, IDMESONET STATION DEHI1 DEER HAVEN.
Jul 4, 7:52 PM MDTTSTM WND GST 491 S Mountain Home Afb, IDMESONET STATION MTHI1 MOUNTAIN HOME AFB RAWS.
Jul 4, 7:52 PM MDTNON-TSTM WND GST 491 S Mountain Home Afb, IDMESONET STATION MTHI1 MOUNTAIN HOME AFB RAWS.
Jul 4, 7:55 PM MDTTSTM WND GST 5317 Wsw Hagerman, IDMESONET STATION TWBI1 TWIN BUTTES.
Jul 4, 7:55 PM MDTNON-TSTM WND GST 5317 Wsw Hagerman, IDMESONET STATION TWBI1 TWIN BUTTES.

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 12:00Z, 2.2 hours before the alert went out and 85 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 12:00Z on 2021-07-04Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 130 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 12:00Z on 2021-07-04The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 21 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
130 J/kg
Mixed-layer CIN
-328 J/kg
Mixed-layer LCL
2872 m above ground
0-6 km bulk shear
17 kt
0-1 km storm-relative helicity
21 m²/s²
0-3 km storm-relative helicity
43 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

038 
WWUS85 KBOI 041410
RFWBOI

URGENT - FIRE WEATHER MESSAGE
National Weather Service Boise ID
810 AM MDT Sun Jul 4 2021


.An upper level impulse will move north into the area today
and help create scattered thunderstorm coverage. Wetting rains
are likely in the cores of the stronger storms as there is 
sufficient moisture, but weaker cells still capable of lightning
will be mostly dry. Much drier air moves in tomorrow, so this is
the last day in this period of thunderstorm activity.

IDZ403-421-423-424-426-ORZ636-637-042130-
/O.NEW.KBOI.FW.W.0007.210704T1800Z-210705T0500Z/
Northern Boise National Forest-
Southern Boise National Forest/Western Sawtooth National Forest-
Owyhee Mountains-Western Twin Falls BLM-Southern Highlands-
Burns BLM-Vale BLM-
810 AM MDT Sun Jul 4 2021 /710 AM PDT Sun Jul 4 2021/

...RED FLAG WARNING IN EFFECT FROM NOON MDT /11 AM PDT/ TODAY TO
11 PM MDT /10 PM PDT/ THIS EVENING FOR LIGHTNING FOR NORTHERN
BOISE NATIONAL FOREST...SOUTHERN BOISE NATIONAL FOREST/WESTERN
SAWTOOTH NATIONAL FOREST...OWYHEE MOUNTAINS...WESTERN TWIN FALLS
BLM...SOUTHERN HIGHLANDS...BURNS BLM AND VALE BLM...WHICH ARE
FIRE WEATHER ZONES 403...421...423...424...426...636 AND 637...

The National Weather Service in Boise has issued a Red Flag
Warning, which is in effect from noon MDT /11 AM PDT/ today to
11 PM MDT /10 PM PDT/ this evening. 

* THUNDERSTORMS...Scattered thunderstorms will develop early this
  afternoon in southern areas, spreading north late this afternoon
  and this evening.

* OUTFLOW WINDS...Gusts to 50 mph are possible with the stronger
  storms, while gusts to 35 mph will be common.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Red Flag Warning means that critical fire weather conditions
are either occurring now, or will occur shortly.

&&

$$


L
2 follow-up statements
292 
WWUS85 KBOI 042043
RFWBOI

URGENT - FIRE WEATHER MESSAGE
National Weather Service Boise ID
243 PM MDT Sun Jul 4 2021

.An upper level impulse will move north into the area today and
help create scattered thunderstorm coverage. Wetting rains are
likely in the cores of the stronger storms as there is sufficient
moisture, but weaker cells still capable of lightning will be
mostly dry. The eastern edge of Eastern Payette NF may see
abundant lightning, but confidence is not high enough to add that
district to the RFW. Gust front winds could hit 60 mph in 
isolated cases, with 30-50 mph more common.

IDZ403-421-423-424-426-ORZ636-637-050445-
/O.CON.KBOI.FW.W.0007.000000T0000Z-210705T0500Z/
Northern Boise National Forest-
Southern Boise National Forest/Western Sawtooth National Forest-
Owyhee Mountains-Western Twin Falls BLM-Southern Highlands-
Burns BLM-Vale BLM-
243 PM MDT Sun Jul 4 2021 /143 PM PDT Sun Jul 4 2021/

...RED FLAG WARNING REMAINS IN EFFECT UNTIL 11 PM MDT /10 PM PDT/
THIS EVENING FOR LIGHTNING FOR NORTHERN BOISE NATIONAL FOREST...
SOUTHERN BOISE NATIONAL FOREST/WESTERN SAWTOOTH NATIONAL FOREST...
OWYHEE MOUNTAINS...WESTERN TWIN FALLS BLM...SOUTHERN HIGHLANDS...
BURNS BLM AND VALE BLM...WHICH ARE FIRE WEATHER ZONES 403...421...
423...424...426...636 AND 637...

* THUNDERSTORMS...Scattered thunderstorms that have developed
  early this afternoon in southern areas will spread into northern
  areas this evening. 

* OUTFLOW WINDS...Gusts to 60 mph are possible with the stronger
  storms, while gusts 30-50 mph will be common. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Red Flag Warning means that critical fire weather conditions
are either occurring now, or will occur shortly.

&&

$$


W L
799 
WWUS85 KBOI 050452
RFWBOI

URGENT - FIRE WEATHER MESSAGE
National Weather Service Boise ID
1052 PM MDT Sun Jul 4 2021

IDZ403-421-423-424-426-ORZ636-637-050600-
/O.EXP.KBOI.FW.W.0007.000000T0000Z-210705T0500Z/
Northern Boise National Forest-
Southern Boise National Forest/Western Sawtooth National Forest-
Owyhee Mountains-Western Twin Falls BLM-Southern Highlands-
Burns BLM-Vale BLM-
1052 PM MDT Sun Jul 4 2021 /952 PM PDT Sun Jul 4 2021/

...RED FLAG WARNING WILL EXPIRE AT 11 PM MDT /10 PM PDT/ THIS
EVENING FOR LIGHTNING FOR NORTHERN BOISE NATIONAL FOREST...
SOUTHERN BOISE NATIONAL FOREST/WESTERN SAWTOOTH NATIONAL FOREST...
OWYHEE MOUNTAINS...WESTERN TWIN FALLS BLM...SOUTHERN HIGHLANDS...
BURNS BLM AND VALE BLM...WHICH ARE FIRE WEATHER ZONES 403...421...
423...424...426...636 AND 637...

Thunderstorms across the warned area have weakened so that
lightning and gusty wind are no longer expected to be  
significant threats overnight. Therefore, the Red Flag Warning 
will be allowed to expire. 

$$


L

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 4, 5:04 PM MDTSpecial Weather StatementBOIOwyhee41 min
Jul 4, 5:45 PM MDTSpecial Weather StatementBOIOwyhee45 min

Nearby

Red Flag Warnings in Idaho, 2021Red Flag Warnings in Oregon, 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.