Alert archive / Idaho / Red Flag Warnings in 2021

Red Flag Warning 11, NWS Boise, ID

August 4, 202116 counties in Idaho

NWS Boise, ID issued this red flag warning at Aug 4, 2021, 2:34 PM MDT for 16 counties in Idaho. It took effect at Aug 5, 2021, 12:00 PM MDT. It was in force for 21 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
Aug 4, 2021, 2:34 PM MDT (20:34 UTC)
In effect from
Aug 5, 2021, 12:00 PM MDT
Expired
Aug 6, 2021, 9:00 AM MDT
In force
21 hr
Issued by
NWS Boise, ID

Counties Ada County, ID, Adams County, ID, Boise County, ID, Camas County, ID, Canyon County, ID, Elmore County, ID, Gem County, ID, Gooding County, ID, Idaho County, ID, Jerome County, ID, Lincoln County, ID, Owyhee County, ID, Payette County, ID, Twin Falls County, ID, Valley County, ID, Washington County, ID

The radar

The Boise radar (KCBX), 53 km from the middle of the area, began a volume at 20:34 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 12:00Z, 8.6 hours before the alert went out and 47 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 2021-08-04Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 28 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Boise Airport, ID at 12:00Z on 2021-08-04The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 45 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
28 J/kg
Mixed-layer CIN
-486 J/kg
Mixed-layer LCL
2886 m above ground
0-6 km bulk shear
35 kt
0-1 km storm-relative helicity
45 m²/s²
0-3 km storm-relative helicity
67 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

528 
WWUS85 KBOI 042034
RFWBOI

URGENT - FIRE WEATHER MESSAGE
National Weather Service Boise ID
234 PM MDT Wed Aug 4 2021

...LOW HUMIDITY AND GUSTY WIND EXPECTED ACROSS EXTREME 
SOUTHEASTERN OREGON ON THURSDAY... 

...SCATTERED THUNDERSTORMS ACROSS REMAINING AREAS OF EASTERN 
OREGON AND IDAHO MOUNTAINS ON THURSDAY AFTERNOON AND EVENING...

.The incoming trough remains generally on track to impact the area
on Thursday and Thursday evening. Areas of southeastern Oregon can
expect a critical combination of gusty winds and low humidity
during the afternoon. Meanwhile, scattered thunderstorms will be
possible across the remainder of the warned area. Gusty winds of
40 to 50 mph could be possible with any storm development on
Thursday. 

ORZ636-637-052200-
/O.UPG.KBOI.FW.A.0007.210805T1800Z-210806T0600Z/
/O.NEW.KBOI.FW.W.0011.210805T1800Z-210806T0600Z/
Burns BLM-Vale BLM-
234 PM MDT Wed Aug 4 2021 /134 PM PDT Wed Aug 4 2021/

...RED FLAG WARNING IN EFFECT FROM NOON MDT /11 AM PDT/ THURSDAY
TO MIDNIGHT MDT /11 PM PDT/ THURSDAY NIGHT FOR...GUSTY WINDS AND
LOW RELATIVE HUMIDITIES AND LIGHTNING FOR BURNS BLM AND VALE
BLM...WHICH ARE FIRE WEATHER ZONES 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/ Thursday to
midnight MDT /11 PM PDT/ Thursday night. The Fire Weather Watch
is no longer in effect. 

* WINDS...For the southern portions of zones 636 and 637, winds of
  15 to 20 with gusts to 35 mph. For zone 646 and the northern 
  portions of zones 636 and 637, winds will be 5 to 10 with gusts 
  to 20 mph outside of thunderstorms. 

* RELATIVE HUMIDITY...8 to 14 percent for zones 636 and 637.

* THUNDERSTORMS...Scattered thunderstorms anticipated for the 
  northern portions of 636 and 637 and across zone 646 for 
  Thursday afternoon and evening.

* OUTFLOW WINDS...Thunderstorms favored to produce outflow winds
  as strong as 40 to 50 mph. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

$$

ORZ646-052200-
/O.UPG.KBOI.FW.A.0007.210805T1800Z-210806T0600Z/
/O.NEW.KBOI.FW.W.0011.210805T1800Z-210806T0600Z/
Baker Valley-
134 PM PDT Wed Aug 4 2021

...RED FLAG WARNING IN EFFECT FROM 11 AM TO 11 PM PDT THURSDAY
FOR...LIGHTNING FOR BAKER VALLEY...WHICH IS FIRE WEATHER ZONE 
646...

The National Weather Service in Boise has issued a Red Flag
Warning, which is in effect from 11 AM to 11 PM PDT Thursday. The
Fire Weather Watch is no longer in effect. 

* THUNDERSTORMS...Scattered thunderstorms expected for the across
  the area for Thursday afternoon and evening. Storms could
  produce brief periods of heavy rain, abundant lightning, and 
  gusty and erratic winds.

* OUTFLOW WINDS...Thunderstorms may produce outflow winds of 40 to
  50 mph. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

$$

IDZ400>403-052200-
/O.NEW.KBOI.FW.W.0011.210805T1800Z-210806T0600Z/
Northern Boise BLM-Western Payette National Forest-
Eastern Payette National Forest-Northern Boise National Forest-
234 PM MDT Wed Aug 4 2021

...RED FLAG WARNING IN EFFECT FROM NOON THURSDAY TO MIDNIGHT MDT
THURSDAY NIGHT FOR...LIGHTNING FOR NORTHERN BOISE BLM...WESTERN 
PAYETTE NATIONAL FOREST...EASTERN PAYETTE NATIONAL FOREST AND 
NORTHERN BOISE NATIONAL FOREST...WHICH ARE FIRE WEATHER ZONES 
400...401... 402 AND 403...

The National Weather Service in Boise has issued a Red Flag
Warning, which is in effect from noon Thursday to midnight MDT
Thursday night. 

* THUNDERSTORMS...Scattered thunderstorms expected for the across
  the area for Thursday afternoon and evening. Storms could
  produce brief periods of heavy rain, abundant lightning, and 
  gusty and erratic winds.

* OUTFLOW WINDS...Thunderstorms may produce outflow winds of 40 to
  50 mph. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

$$


W L
6 follow-up statements
525 
WWUS85 KBOI 051525
RFWBOI

URGENT - FIRE WEATHER MESSAGE
National Weather Service Boise ID
925 AM MDT Thu Aug 5 2021

...LOW HUMIDITY AND GUSTY WIND EXPECTED ACROSS EXTREME
SOUTHEASTERN OREGON THIS AFTERNOON...

...SCATTERED THUNDERSTORMS WITH STRONG ACROSS REMAINING AREAS OF 
EASTERN OREGON AND IDAHO MOUNTAINS BEGINNING THIS AFTERNOON...

.Dry and windy conditions expected this afternoon across
southeastern Oregon, with isolated to scattered showers and 
thunderstorms expected across the remainder of eastern Oregon and 
into Idaho. This trough is expected to continue thunderstorms 
through the overnight hours with gusty to breezy winds continuing.
Because of the continued critical conditions overnight, some 
areas have been extended. Improved conditions expected on Friday 
as the trough moves eastward.

IDZ420-424-060600-
/O.EXA.KBOI.FW.W.0011.210805T1800Z-210806T0600Z/
Treasure Valley BLM-Western Twin Falls BLM-
925 AM MDT Thu Aug 5 2021

...RED FLAG WARNING IN EFFECT UNTIL MIDNIGHT MDT TONIGHT FOR...
LIGHTNING FOR TREASURE VALLEY BLM AND WESTERN TWIN FALLS 
BLM...WHICH ARE FIRE WEATHER ZONES 420 AND 424...

The National Weather Service in Boise has issued a Red Flag
Warning, which is in effect until midnight MDT tonight. 

* THUNDERSTORMS...Scattered thunderstorms expected for the across
  the area through early Friday. Storms could produce abundant 
  lightning, and strong and erratic winds. 

* OUTFLOW WINDS...Thunderstorms may produce outflow winds of 40 
  to 55 mph. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

$$

IDZ401-402-ORZ646-061200-
/O.EXT.KBOI.FW.W.0011.210805T1800Z-210806T1200Z/
Western Payette National Forest-Eastern Payette National Forest-
Baker Valley-
925 AM MDT Thu Aug 5 2021 /825 AM PDT Thu Aug 5 2021/

...RED FLAG WARNING NOW IN EFFECT UNTIL 6 AM MDT /5 AM PDT/
FRIDAY FOR...LIGHTNING FOR WESTERN PAYETTE NATIONAL 
FOREST...EASTERN PAYETTE NATIONAL FOREST AND BAKER VALLEY...WHICH 
ARE FIRE WEATHER ZONES 401...402 AND 646...

* THUNDERSTORMS...Scattered thunderstorms expected for the across
  the area through early Friday morning. Storms could produce 
  abundant lightning, and gusty and erratic winds. 

* OUTFLOW WINDS...Thunderstorms may produce outflow winds of 40 
  to 50 mph. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

$$

ORZ637-061200-
/O.EXT.KBOI.FW.W.0011.210805T1800Z-210806T1200Z/
Vale BLM-
925 AM MDT Thu Aug 5 2021 /825 AM PDT Thu Aug 5 2021/

...RED FLAG WARNING NOW IN EFFECT UNTIL 6 AM MDT /5 AM PDT/
FRIDAY FOR...GUSTY WINDS AND LOW RELATIVE HUMIDITIES AND
LIGHTNING FOR VALE BLM...WHICH IS FIRE WEATHER ZONE 637...

* WINDS...For the southern portions, winds of 15 to 20 with gusts
  to 35 mph.  

* RELATIVE HUMIDITY...8 to 14 percent.

* THUNDERSTORMS...Scattered thunderstorms anticipated for the
  northern portions of the zone through early Friday morning.

* OUTFLOW WINDS...Thunderstorms favored to produce outflow 
  winds as strong as 40 to 55 mph. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

$$

ORZ636-060600-
/O.CON.KBOI.FW.W.0011.210805T1800Z-210806T0600Z/
Burns BLM-
825 AM PDT Thu Aug 5 2021

...RED FLAG WARNING REMAINS IN EFFECT UNTIL 11 PM PDT THIS
EVENING FOR...GUSTY WINDS AND LOW RELATIVE HUMIDITIES AND
LIGHTNING FOR BURNS BLM...WHICH IS FIRE WEATHER ZONE 636...

* WINDS...For the southern portions of the zone, winds of 15 to 20
  with gusts to 35 mph.  

* RELATIVE HUMIDITY...8 to 14 percent.

* THUNDERSTORMS...Scattered thunderstorms anticipated for the
  northern portions of the zone for this afternoon and evening.

* OUTFLOW WINDS...Thunderstorms favored to produce outflow winds
  as strong as 40 to 55 mph. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

$$

IDZ400-403-060600-
/O.CON.KBOI.FW.W.0011.210805T1800Z-210806T0600Z/
Northern Boise BLM-Northern Boise National Forest-
925 AM MDT Thu Aug 5 2021

...RED FLAG WARNING REMAINS IN EFFECT UNTIL MIDNIGHT MDT TONIGHT
FOR...GUSTY WINDS AND LOW RELATIVE HUMIDITIES AND LIGHTNING FOR
NORTHERN BOISE BLM AND NORTHERN BOISE NATIONAL FOREST...WHICH ARE
FIRE WEATHER ZONES 400 AND 403...

* THUNDERSTORMS...Scattered thunderstorms expected for the
  across the area for this afternoon and evening. Storms could
  produce abundant lightning, and gusty and erratic winds. 

* OUTFLOW WINDS...Thunderstorms may produce outflow winds of 40 
  to 50 mph. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

$$


W L
767 
WWUS85 KBOI 052029
RFWBOI

URGENT - FIRE WEATHER MESSAGE
National Weather Service Boise ID
229 PM MDT Thu Aug 5 2021

...LOW HUMIDITY AND GUSTY WIND EXPECTED ACROSS EXTREME
SOUTHEASTERN OREGON THROUGH THE AFTERNOON...

...SCATTERED THUNDERSTORMS WITH STRONG WIND ACROSS REMAINING 
AREAS OF EASTERN OREGON AND IDAHO INTO FRIDAY MORNING...

.Dry and windy conditions expected this afternoon across
southeastern Oregon, with isolated to scattered showers and
thunderstorms expected across the remainder of eastern Oregon and
into Idaho. The influencing trough is expected to continue 
thunderstorms through the overnight hours with gusty to breezy 
winds. Because of the continued critical conditions overnight, 
some areas have been extended. Improved conditions expected on 
Friday as the trough moves eastward.

ORZ636-060600-
/O.CON.KBOI.FW.W.0011.000000T0000Z-210806T0600Z/
Burns BLM-
129 PM PDT Thu Aug 5 2021

...RED FLAG WARNING REMAINS IN EFFECT UNTIL 11 PM PDT THIS
EVENING FOR BURNS BLM...WHICH IS FIRE WEATHER ZONE 636...

* WINDS...For the southern portions of the zone, winds of 15 to 
  20 with gusts to 35 mph. 

* RELATIVE HUMIDITY...8 to 14 percent.

* THUNDERSTORMS...Scattered thunderstorms anticipated for the 
  northern portions of the zone for this afternoon and evening.

* OUTFLOW WINDS...Thunderstorms favored to produce outflow 
  winds as strong as 40 to 55 mph. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

$$

IDZ400-403-060600-
/O.CON.KBOI.FW.W.0011.000000T0000Z-210806T0600Z/
Northern Boise BLM-Northern Boise National Forest-
229 PM MDT Thu Aug 5 2021

...RED FLAG WARNING REMAINS IN EFFECT UNTIL MIDNIGHT MDT TONIGHT
FOR NORTHERN BOISE BLM AND NORTHERN BOISE NATIONAL FOREST...WHICH
ARE FIRE WEATHER ZONES 400 AND 403...

* THUNDERSTORMS...Scattered thunderstorms expected for the 
  across the area for this afternoon and evening. Storms could 
  produce abundant lightning, and gusty and erratic winds. 

* OUTFLOW WINDS...Thunderstorms may produce outflow winds of 40 to
  55 mph.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

$$

IDZ420-424-060600-
/O.CON.KBOI.FW.W.0011.000000T0000Z-210806T0600Z/
Treasure Valley BLM-Western Twin Falls BLM-
229 PM MDT Thu Aug 5 2021

...RED FLAG WARNING REMAINS IN EFFECT UNTIL MIDNIGHT MDT TONIGHT
FOR TREASURE VALLEY BLM AND WESTERN TWIN FALLS BLM...WHICH ARE
FIRE WEATHER ZONES 420 AND 424...

* THUNDERSTORMS...Scattered thunderstorms expected for the across  
  the area through early Friday. Storms could produce abundant 
  lightning, and strong and erratic winds. 

* OUTFLOW WINDS...Thunderstorms may produce outflow winds of 40 
  to 55 mph.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

$$

IDZ401-402-ORZ646-061200-
/O.CON.KBOI.FW.W.0011.000000T0000Z-210806T1200Z/
Western Payette National Forest-Eastern Payette National Forest-
Baker Valley-
229 PM MDT Thu Aug 5 2021 /129 PM PDT Thu Aug 5 2021/

...RED FLAG WARNING REMAINS IN EFFECT UNTIL 6 AM MDT /5 AM PDT/
FRIDAY FOR WESTERN PAYETTE NATIONAL FOREST...EASTERN PAYETTE
NATIONAL FOREST AND BAKER VALLEY...WHICH ARE FIRE WEATHER ZONES
401...402 AND 646...

* THUNDERSTORMS...Scattered thunderstorms expected across the 
  area through early Friday morning. Storms could produce abundant
  lightning, and gusty and erratic winds. 

* OUTFLOW WINDS...Thunderstorms may produce outflow winds of 40 to
  55 mph.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

$$

ORZ637-061200-
/O.CON.KBOI.FW.W.0011.000000T0000Z-210806T1200Z/
Vale BLM-
229 PM MDT Thu Aug 5 2021 /129 PM PDT Thu Aug 5 2021/

...RED FLAG WARNING REMAINS IN EFFECT UNTIL 6 AM MDT /5 AM PDT/
FRIDAY FOR VALE BLM...WHICH IS FIRE WEATHER ZONE 637...

* WINDS...For the southern portions, winds of 15 to 20 with 
  gusts to 35 mph. 

* RELATIVE HUMIDITY...8 to 14 percent.

* THUNDERSTORMS...Scattered thunderstorms anticipated for the 
  northern portions of the zone through early Friday morning.

* OUTFLOW WINDS...Thunderstorms favored to produce outflow 
  winds as strong as 40 to 55 mph.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

$$


W L
067 
WWUS85 KBOI 060600
RFWBOI

URGENT - FIRE WEATHER MESSAGE
National Weather Service Boise ID
1200 AM MDT Fri Aug 6 2021

...LOW HUMIDITY AND GUSTY WIND EXPECTED ACROSS EXTREME
SOUTHEASTERN OREGON THROUGH THE AFTERNOON...

...SCATTERED THUNDERSTORMS WITH STRONG WIND ACROSS REMAINING
AREAS OF EASTERN OREGON AND IDAHO INTO FRIDAY MORNING...

.Isolated to scattered showers and thunderstorms expected across 
the warning area into Friday morning. In addition, strong winds
will continue even as RH values rise overnight. Because of the 
continued critical conditions overnight, some areas have been 
extended. Improved conditions expected Friday afternoon as the 
trough moves eastward, but breezy conditions will remain.

ORZ646-060700-
/O.CAN.KBOI.FW.W.0011.000000T0000Z-210806T1200Z/
Baker Valley-
1100 PM PDT Thu Aug 5 2021

...RED FLAG WARNING IS CANCELLED FOR...GUSTY WINDS AND LOW
RELATIVE HUMIDITIES AND LIGHTNING FOR BAKER VALLEY...WHICH IS
FIRE WEATHER ZONE 646...

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

Relative humidity has come up and storms are moving out of the
area. Therefore the warning will be allowed to expire.

$$

ORZ636-060700-
/O.EXP.KBOI.FW.W.0011.000000T0000Z-210806T0600Z/
Burns BLM-
1100 PM PDT Thu Aug 5 2021

...RED FLAG WARNING WILL EXPIRE AT 11 PM PDT THIS EVENING FOR...
GUSTY WINDS AND LOW RELATIVE HUMIDITIES AND LIGHTNING FOR BURNS
BLM...WHICH IS FIRE WEATHER ZONE 636...

Relative humidity has come up and storms are moving out of the
area. Therefore the warning will be allowed to expire.

$$

IDZ421-061400-
/O.EXB.KBOI.FW.W.0011.000000T0000Z-210806T1500Z/
Southern Boise National Forest/Western Sawtooth National Forest-
1200 AM MDT Fri Aug 6 2021

...RED FLAG WARNING IN EFFECT UNTIL 9 AM MDT FRIDAY FOR...GUSTY
WINDS AND LOW RELATIVE HUMIDITIES AND LIGHTNING FOR SOUTHERN
BOISE NATIONAL FOREST/WESTERN SAWTOOTH NATIONAL FOREST...WHICH IS
FIRE WEATHER ZONE 421...

The National Weather Service in Boise has issued a Red Flag
Warning, which is in effect until 9 AM MDT Friday. 

* THUNDERSTORMS...Isolated to scattered thunderstorms expected 
  for the across the area into Friday morning. Storms could 
  produce abundant lightning, and gusty and erratic winds. 

* OUTFLOW WINDS...Thunderstorms may produce outflow winds of 40 to
  50 mph. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

$$

IDZ400-403-061400-
/O.EXT.KBOI.FW.W.0011.000000T0000Z-210806T1500Z/
Northern Boise BLM-Northern Boise National Forest-
1200 AM MDT Fri Aug 6 2021

...RED FLAG WARNING NOW IN EFFECT UNTIL 9 AM MDT FRIDAY FOR...
GUSTY WINDS AND LOW RELATIVE HUMIDITIES AND LIGHTNING FOR
NORTHERN BOISE BLM AND NORTHERN BOISE NATIONAL FOREST...WHICH ARE
FIRE WEATHER ZONES 400 AND 403...

* THUNDERSTORMS...Isolated to scattered thunderstorms expected for
  the across the area into Friday morning. Storms could produce 
  abundant lightning, and gusty and erratic winds. 

* OUTFLOW WINDS...Thunderstorms may produce outflow winds of 40 to
  50 mph. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

$$

IDZ420-424-061400-
/O.EXT.KBOI.FW.W.0011.000000T0000Z-210806T1500Z/
Treasure Valley BLM-Western Twin Falls BLM-
1200 AM MDT Fri Aug 6 2021

...RED FLAG WARNING NOW IN EFFECT UNTIfor the northern portions of
the zone L 9 AM MDT FRIDAY FOR... GUSTY WINDS AND LOW RELATIVE 
HUMIDITIES AND LIGHTNING FOR TREASURE VALLEY BLM AND WESTERN TWIN 
FALLS BLM...WHICH ARE FIRE WEATHER ZONES 420 AND 424...

* THUNDERSTORMS...Isolated to scattered thunderstorms expected 
  for the across the area through early Friday. Storms could 
  produce abundant lightning, and strong and erratic winds. 

* OUTFLOW WINDS...Thunderstorms may produce outflow winds of 40 to
  50 mph.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

$$

IDZ401-402-061400-
/O.EXT.KBOI.FW.W.0011.000000T0000Z-210806T1500Z/
Western Payette National Forest-Eastern Payette National Forest-
1200 AM MDT Fri Aug 6 2021

...RED FLAG WARNING NOW IN EFFECT UNTIL 9 AM MDT FRIDAY FOR...
GUSTY WINDS AND LOW RELATIVE HUMIDITIES AND LIGHTNING FOR WESTERN
PAYETTE NATIONAL FOREST AND EASTERN PAYETTE NATIONAL FOREST...
WHICH ARE FIRE WEATHER ZONES 401 AND 402...

* THUNDERSTORMS...Isolated to scattered thunderstorms expected 
  across the area through early Friday morning. Storms could 
  produce abundant lightning, and gusty and erratic winds. 

* OUTFLOW WINDS...Thunderstorms may produce outflow winds of 40 
  to 50 mph. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

$$

ORZ637-061200-
/O.CON.KBOI.FW.W.0011.000000T0000Z-210806T1200Z/
Vale BLM-
1200 AM MDT Fri Aug 6 2021 /1100 PM PDT Thu Aug 5 2021/

...RED FLAG WARNING REMAINS IN EFFECT UNTIL 6 AM MDT /5 AM PDT/
FRIDAY FOR...GUSTY WINDS AND LOW RELATIVE HUMIDITIES AND
LIGHTNING FOR VALE BLM...WHICH IS FIRE WEATHER ZONE 637...

* WINDS...For the southern portions, winds of 15 to 20 with 
  gusts to 35 mph. 

* RELATIVE HUMIDITY...8 to 14 percent.

* THUNDERSTORMS...Isolated to scattered thunderstorms anticipated
  into Friday morning.

* OUTFLOW WINDS...Thunderstorms favored to produce outflow winds
  as strong as 40 to 50 mph.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

$$


W L
550 
WWUS85 KBOI 060616 CCA
RFWBOI

URGENT - FIRE WEATHER MESSAGE...CORRECTED
National Weather Service Boise ID
1216 AM MDT Fri Aug 6 2021

...LOW HUMIDITY AND GUSTY WIND EXPECTED ACROSS EXTREME
SOUTHEASTERN OREGON THROUGH THE AFTERNOON...

...SCATTERED THUNDERSTORMS WITH STRONG WIND ACROSS REMAINING
AREAS OF EASTERN OREGON AND IDAHO INTO FRIDAY MORNING...

.Isolated to scattered showers and thunderstorms expected across 
the warning area into Friday morning. In addition, strong winds
will continue even as RH values rise overnight. Because of the 
continued critical conditions overnight, some areas have been 
extended. Improved conditions expected Friday afternoon as the 
trough moves eastward, but breezy conditions will remain.

ORZ646-060700-
/O.CAN.KBOI.FW.W.0011.000000T0000Z-210806T1200Z/
Baker Valley-
1116 PM PDT Thu Aug 5 2021

...RED FLAG WARNING IS CANCELLED FOR...GUSTY WINDS AND LOW
RELATIVE HUMIDITIES AND LIGHTNING FOR BAKER VALLEY...WHICH IS
FIRE WEATHER ZONE 646...

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

Relative humidity has come up and storms are moving out of the
area. Therefore the warning will be allowed to expire.

$$

ORZ636-060700-
/O.EXP.KBOI.FW.W.0011.000000T0000Z-210806T0600Z/
Burns BLM-
1116 PM PDT Thu Aug 5 2021

...RED FLAG WARNING WILL EXPIRE AT 11 PM PDT THIS EVENING FOR...
GUSTY WINDS AND LOW RELATIVE HUMIDITIES AND LIGHTNING FOR BURNS
BLM...WHICH IS FIRE WEATHER ZONE 636...

Relative humidity has come up and storms are moving out of the
area. Therefore the warning will be allowed to expire.

$$

IDZ421-061400-
/O.EXB.KBOI.FW.W.0011.000000T0000Z-210806T1500Z/
Southern Boise National Forest/Western Sawtooth National Forest-
1216 AM MDT Fri Aug 6 2021

...RED FLAG WARNING IN EFFECT UNTIL 9 AM MDT FRIDAY FOR...GUSTY
WINDS AND LOW RELATIVE HUMIDITIES AND LIGHTNING FOR SOUTHERN
BOISE NATIONAL FOREST/WESTERN SAWTOOTH NATIONAL FOREST...WHICH IS
FIRE WEATHER ZONE 421...

The National Weather Service in Boise has issued a Red Flag
Warning, which is in effect until 9 AM MDT Friday. 

* THUNDERSTORMS...Isolated to scattered thunderstorms expected 
  for the across the area into Friday morning. Storms could 
  produce abundant lightning, and gusty and erratic winds. 

* OUTFLOW WINDS...Thunderstorms may produce outflow winds of 40 to
  50 mph. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

$$

IDZ400-403-061400-
/O.EXT.KBOI.FW.W.0011.000000T0000Z-210806T1500Z/
Northern Boise BLM-Northern Boise National Forest-
1216 AM MDT Fri Aug 6 2021

...RED FLAG WARNING NOW IN EFFECT UNTIL 9 AM MDT FRIDAY FOR...
GUSTY WINDS AND LOW RELATIVE HUMIDITIES AND LIGHTNING FOR
NORTHERN BOISE BLM AND NORTHERN BOISE NATIONAL FOREST...WHICH ARE
FIRE WEATHER ZONES 400 AND 403...

* THUNDERSTORMS...Isolated to scattered thunderstorms expected for
  the across the area into Friday morning. Storms could produce 
  abundant lightning, and gusty and erratic winds. 

* OUTFLOW WINDS...Thunderstorms may produce outflow winds of 40 to
  50 mph. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

$$

IDZ420-424-061400-
/O.COR.KBOI.FW.W.0011.000000T0000Z-210806T1500Z/
Treasure Valley BLM-Western Twin Falls BLM-
1216 AM MDT Fri Aug 6 2021

...RED FLAG WARNING NOW IN EFFECT UNTIL 9 AM MDT FRIDAY FOR... 
GUSTY WINDS AND LOW RELATIVE HUMIDITIES AND LIGHTNING FOR TREASURE
VALLEY BLM AND WESTERN TWIN FALLS BLM...WHICH ARE FIRE WEATHER 
ZONES 420 AND 424...

* THUNDERSTORMS...Isolated to scattered thunderstorms expected 
  for the across the area through early Friday. Storms could 
  produce abundant lightning, and strong and erratic winds. 

* OUTFLOW WINDS...Thunderstorms may produce outflow winds of 40 to
  50 mph.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

$$

IDZ401-402-061400-
/O.EXT.KBOI.FW.W.0011.000000T0000Z-210806T1500Z/
Western Payette National Forest-Eastern Payette National Forest-
1216 AM MDT Fri Aug 6 2021

...RED FLAG WARNING NOW IN EFFECT UNTIL 9 AM MDT FRIDAY FOR...
GUSTY WINDS AND LOW RELATIVE HUMIDITIES AND LIGHTNING FOR WESTERN
PAYETTE NATIONAL FOREST AND EASTERN PAYETTE NATIONAL FOREST...
WHICH ARE FIRE WEATHER ZONES 401 AND 402...

* THUNDERSTORMS...Isolated to scattered thunderstorms expected 
  across the area through early Friday morning. Storms could 
  produce abundant lightning, and gusty and erratic winds. 

* OUTFLOW WINDS...Thunderstorms may produce outflow winds of 40 
  to 50 mph. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

$$

ORZ637-061200-
/O.CON.KBOI.FW.W.0011.000000T0000Z-210806T1200Z/
Vale BLM-
1216 AM MDT Fri Aug 6 2021 /1116 PM PDT Thu Aug 5 2021/

...RED FLAG WARNING REMAINS IN EFFECT UNTIL 6 AM MDT /5 AM PDT/
FRIDAY FOR...GUSTY WINDS AND LOW RELATIVE HUMIDITIES AND
LIGHTNING FOR VALE BLM...WHICH IS FIRE WEATHER ZONE 637...

* WINDS...For the southern portions, winds of 15 to 20 with 
  gusts to 35 mph. 

* RELATIVE HUMIDITY...8 to 14 percent.

* THUNDERSTORMS...Isolated to scattered thunderstorms anticipated
  into Friday morning.

* OUTFLOW WINDS...Thunderstorms favored to produce outflow winds
  as strong as 40 to 50 mph.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

$$


W L
152 
WWUS85 KBOI 061138
RFWBOI

URGENT - FIRE WEATHER MESSAGE
National Weather Service Boise ID
538 AM MDT Fri Aug 6 2021



...SCATTERED THUNDERSTORMS ACROSS MUCH OF SOUTHWEST IDAHO THIS 
MORNING...

.Isolated to scattered showers and thunderstorms are expected 
across the warning area this morning. Improving conditions are 
expected this afternoon as an upper level trough moves eastward
and away from the area, but breezy conditions will remain.

ORZ637-061245-
/O.EXP.KBOI.FW.W.0011.000000T0000Z-210806T1200Z/
Vale BLM-
538 AM MDT Fri Aug 6 2021 /438 AM PDT Fri Aug 6 2021/

...RED FLAG WARNING WILL EXPIRE AT 6 AM MDT /5 AM PDT/ EARLY THIS
MORNING FOR LIGHTNING FOR VALE BLM...WHICH IS FIRE WEATHER ZONE
637...

Thunderstorms have moved out of the area, and the warning will be
allowed to expire at 6 am MDT / 5 am PDT.

$$

IDZ400-403-061500-
/O.CON.KBOI.FW.W.0011.000000T0000Z-210806T1500Z/
Northern Boise BLM-Northern Boise National Forest-
538 AM MDT Fri Aug 6 2021

...RED FLAG WARNING REMAINS IN EFFECT UNTIL 9 AM MDT THIS MORNING
FOR LIGHTNING FOR NORTHERN BOISE BLM AND NORTHERN BOISE NATIONAL
FOREST...WHICH ARE FIRE WEATHER ZONES 400 AND 403...

* THUNDERSTORMS...Isolated to scattered thunderstorms expected
  across the area this morning. Storms could produce abundant 
  lightning, and gusty and erratic winds. 

* OUTFLOW WINDS...Thunderstorms may produce outflow winds of40 
  to 50 mph. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

$$

IDZ420-424-061500-
/O.CON.KBOI.FW.W.0011.000000T0000Z-210806T1500Z/
Treasure Valley BLM-Western Twin Falls BLM-
538 AM MDT Fri Aug 6 2021

...RED FLAG WARNING REMAINS IN EFFECT UNTIL 9 AM MDT THIS MORNING
FOR LIGHTNING FOR TREASURE VALLEY BLM AND WESTERN TWIN FALLS
BLM...WHICH ARE FIRE WEATHER ZONES 420 AND 424...

* THUNDERSTORMS...Isolated to scattered thunderstorms expected
  across the area this morning. Storms could produce abundant 
  lightning, and strong and erratic winds. 

* OUTFLOW WINDS...Thunderstorms may produce outflow winds of 40 
  to 50 mph. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

$$

IDZ401-402-421-061500-
/O.CON.KBOI.FW.W.0011.000000T0000Z-210806T1500Z/
Western Payette National Forest-Eastern Payette National Forest-
Southern Boise National Forest/Western Sawtooth National Forest-
538 AM MDT Fri Aug 6 2021

...RED FLAG WARNING REMAINS IN EFFECT UNTIL 9 AM MDT THIS MORNING
FOR LIGHTNING FOR WESTERN PAYETTE NATIONAL FOREST...EASTERN
PAYETTE NATIONAL FOREST AND SOUTHERN BOISE NATIONAL FOREST/ 
WESTERN SAWTOOTH NATIONAL FOREST...WHICH ARE FIRE WEATHER ZONES 
401...402 AND 421...

* THUNDERSTORMS...Isolated to scattered thunderstorms expected
  across the area this morning. Storms could produce abundant 
  lightning, and gusty and erratic winds. 

* OUTFLOW WINDS...Thunderstorms may produce outflow winds of 40 
  to 50 mph. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

$$


L
573 
WWUS85 KBOI 061446
RFWBOI

URGENT - FIRE WEATHER MESSAGE
National Weather Service Boise ID
846 AM MDT Fri Aug 6 2021

IDZ400-403-061600-
/O.EXP.KBOI.FW.W.0011.000000T0000Z-210806T1500Z/
Northern Boise BLM-Northern Boise National Forest-
846 AM MDT Fri Aug 6 2021

...RED FLAG WARNING WILL EXPIRE AT 9 AM MDT THIS MORNING FOR
LIGHTNING FOR NORTHERN BOISE BLM AND NORTHERN BOISE NATIONAL
FOREST...WHICH ARE FIRE WEATHER ZONES 400 AND 403...

Thunderstorms are decreasing in coverage and moving east of the
area this morning. There is a slight chance of thunderstorms in
the eastern portion of zone 403 this afternoon, but coverage is
anticipated to be isolated.

$$

IDZ420-424-061600-
/O.EXP.KBOI.FW.W.0011.000000T0000Z-210806T1500Z/
Treasure Valley BLM-Western Twin Falls BLM-
846 AM MDT Fri Aug 6 2021

...RED FLAG WARNING WILL EXPIRE AT 9 AM MDT THIS MORNING FOR
LIGHTNING FOR TREASURE VALLEY BLM AND WESTERN TWIN FALLS BLM...
WHICH ARE FIRE WEATHER ZONES 420 AND 424...

Thunderstorms are decreasing in coverage and moving east of the
area this morning. 

$$

IDZ401-402-421-061600-
/O.EXP.KBOI.FW.W.0011.000000T0000Z-210806T1500Z/
Western Payette National Forest-Eastern Payette National Forest-
Southern Boise National Forest/Western Sawtooth National Forest-
846 AM MDT Fri Aug 6 2021

...RED FLAG WARNING WILL EXPIRE AT 9 AM MDT THIS MORNING FOR
LIGHTNING FOR WESTERN PAYETTE NATIONAL FOREST...EASTERN PAYETTE
NATIONAL FOREST AND SOUTHERN BOISE NATIONAL FOREST/WESTERN
SAWTOOTH NATIONAL FOREST...WHICH ARE FIRE WEATHER ZONES 401...
402 AND 421...

Thunderstorms are decreasing in coverage and moving east of the
area this morning. There is a slight chance of thunderstorms in
the eastern portion of zones 402 and 421 this afternoon, but 
coverage is anticipated to be isolated.

$$


L

What forecasters said that day

The local office's own words before this red flag warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Boise, ID wrote its last area forecast discussion before this red flag warning went out at Aug 4, 2:25 PM MDT, 9 minutes earlier.

Area forecast discussion, Aug 4, 2:25 PM MDT, 9 minutes before
Area Forecast Discussion
National Weather Service Boise ID
225 PM MDT Wed Aug 4 2021

.SHORT TERM...Tonight through Friday night...Thunderstorms this
evening working with a very hot airmass, and relatively dry lower
levels, so wind gust threat remains high through the evening. Low
off the CA coast approaches the area for Thursday. Quite a bit of
clouds over the area in the morning according to most models,
which may inhibit storm development early Thursday. But, increased
moisture, shear, and instability should overcome that by late
afternoon, and several models have impressive looking
thunderstorms over the area Thursday evening, as a cold front
moves through from the west, and continuing into early Friday as
the low moves overhead. Some of these storms could be severe. By
Friday afternoon, most of the storms should move into eastern ID,
with some cooler, northwest winds over much of southwest ID and
eastern OR.

.LONG TERM...Saturday through Wednesday...Dry westerly flow aloft
south of an upper level low pressure trough will keep skies mostly
clear over the weekend. Any showers associated with the trough are
expected to reach no farther south than the west central Idaho
mountains. The pattern becomes more uncertain starting Monday, but
models agree that the trough will keep temperatures a few degrees
below normal through Tuesday. Wednesday could be warmer, as some of
the ensembles are showing the flow shifting into the southwest as an
upper level high pressure ridge strengthens over the central Rockies
and four corners.

&&

.AVIATION...Generally VFR. Isolated thunderstorms ending in most
areas by 06z, but continuing overnight in the central Idaho
mountains and Baker Co. Oregon. Widespread showers and isolated
thunderstorms on Thursday. Wildfire smoke layers aloft reducing
visibility. Surface winds: variable 10 kts or less, except gusts 40-
50 kts possible near thunderstorms. Winds aloft at 10k feet MSL:
southwest 10-20 kts.

&&

.BOI WATCHES/WARNINGS/ADVISORIES...
ID...Red Flag Warning from noon Thursday to midnight MDT Thursday
     night IDZ400>403.
OR...Red Flag Warning from noon MDT /11 AM PDT/ Thursday to midnight
     MDT /11 PM PDT/ Thursday night ORZ636-637-646.

&&

www.weather.gov/Boise
www.facebook.com/NWSBoise
www.twitter.com/NWSBoise

SHORT TERM...TB
LONG TERM....JT
AVIATION.....JT

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 3, 6:05 PM MDTSpecial Weather StatementBOICanyon55 min
Aug 3, 6:16 PM MDTSpecial Weather StatementBOICanyon44 min
Aug 3, 6:32 PM MDTSpecial Weather StatementBOI28 min
Aug 3, 7:02 PM MDTSpecial Weather StatementBOIAda, Canyon43 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.