Alert archive / California / Red Flag Warnings in 2021

Red Flag Warning 3, NWS San Diego, CA

November 19, 20214 counties in California

NWS San Diego, CA issued this red flag warning at Nov 19, 2021, 1:35 PM PST for 4 counties in California. It took effect at Nov 21, 2021, 9:00 AM PST. It was in force for 10 hr. 4 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
Nov 19, 2021, 1:35 PM PST (21:35 UTC)
In effect from
Nov 21, 2021, 9:00 AM PST
Expired
Nov 21, 2021, 7:00 PM PST
In force
10 hr
Issued by
NWS San Diego, CA

Counties Orange County, CA, Riverside County, CA, San Bernardino County, CA, San Diego County, CA

The radar

The Santa Ana Mts radar (KSOX), 88 km from the middle of the area, began a volume at 21:41 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
Nov 21, 9:20 AM PSTNON-TSTM WND GST 672 Ssw Lake Arrowhead, CAARROWHEAD SPRINGS (189SE) PEAK WIND GUST.
Nov 21, 9:30 AM PSTNON-TSTM WND GST 584 Sse Lytle Creek, CADUNCAN CANYON (SCE533) PEAK WIND GUST.
Nov 21, 9:40 AM PSTNON-TSTM WND GST 578 Ne Alpine, CASILL HILL PEAK WIND GUST.
Nov 21, 9:51 AM PSTNON-TSTM WND GST 558 Nne Mission Viejo, CAFREMONT CANYON PEAK WIND GUST.

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The nearest sounding before it

San Diego, CA (KNKX), launched 12:00Z, 9.6 hours before the alert went out and 124 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, San Diego, CA at 12:00Z on 2021-11-19Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 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, San Diego, CA at 12:00Z on 2021-11-19The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 40 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
1842 m above ground
0-6 km bulk shear
27 kt
0-1 km storm-relative helicity
40 m²/s²
0-3 km storm-relative helicity
59 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

540 
WWUS86 KSGX 192135
RFWSGX

URGENT - FIRE WEATHER MESSAGE
National Weather Service San Diego CA
135 PM PST Fri Nov 19 2021


CAZ248-255>257-265-554-200545-
/O.UPG.KSGX.FW.A.0002.211121T1700Z-211122T0300Z/
/O.NEW.KSGX.FW.W.0003.211121T1700Z-211122T0300Z/
San Bernardino and Riverside County Valleys - The Inland Empire-
San Bernardino County Mountains-
Including The Mountain Top And Front Country Ranger Districts Of
The San Bernardino National Forest-Riverside County Mountains-
Including The San Jacinto Ranger District Of The San Bernardino
National Forest-Santa Ana Mountains-
Including The Trabuco Ranger District of the Cleveland National
Forest-San Gorgonio Pass Near Banning-Orange County Inland Areas-
135 PM PST Fri Nov 19 2021

...RED FLAG WARNING IN EFFECT FROM 9 AM TO 7 PM PST SUNDAY FOR
STRONG GUSTY WINDS AND LOW HUMIDITY...

The National Weather Service in San Diego has issued a Red Flag
Warning...which is in effect from 9 AM to 7 PM PST Sunday. The
Fire Weather Watch is no longer in effect. 

* LOCATION...Portions of the Inland Empire, the San Bernardino 
  mountain slopes, the Riverside County mountain slopes, the 
  Santa Ana Mountains and inland Orange County. 

* WIND...Areas of northeast winds 20 to 30 mph with gusts 45 to
  55 mph. Isolated gusts 60 to 65 mph below the Cajon and San 
  Gorgonio Passes, and near the coastal foothills of the Santa 
  Ana Mountains. 

* HUMIDITY...Lowest humidity of 5 to 10 percent Sunday 
  afternoon.

* TIMING...Winds strengthen Saturday night, peak early Sunday 
  morning then begin to weaken Sunday afternoon. Relative 
  humidity begins to decrease late Sunday Morning with only 
  marginal recovery Sunday night.

* IMPACTS...Any fires that develop will likely spread rapidly.
  Outdoor burning is not recommended.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Red Flag Warning means that critical fire weather conditions
are either occurring now....or will shortly. A combination of
strong winds...low relative humidity...and warm temperatures can
contribute to extreme fire behavior.

&&

$$
7 follow-up statements
500 
WWUS86 KSGX 200523
RFWSGX

URGENT - FIRE WEATHER MESSAGE
National Weather Service San Diego CA
923 PM PST Fri Nov 19 2021

CAZ248-255>257-265-554-201400-
/O.CON.KSGX.FW.W.0003.211121T1700Z-211122T0300Z/
San Bernardino and Riverside County Valleys - The Inland Empire-
San Bernardino County Mountains-
Including The Mountain Top And Front Country Ranger Districts Of
The San Bernardino National Forest-Riverside County Mountains-
Including The San Jacinto Ranger District Of The San Bernardino
National Forest-Santa Ana Mountains-
Including The Trabuco Ranger District of the Cleveland National
Forest-San Gorgonio Pass Near Banning-Orange County Inland Areas-
923 PM PST Fri Nov 19 2021

...RED FLAG WARNING REMAINS IN EFFECT FROM 9 AM TO 7 PM PST
SUNDAY FOR STRONG GUSTY WINDS AND LOW HUMIDITY...

* LOCATION...Portions of the Inland Empire, the San Bernardino 
  mountain slopes, the Riverside County mountain slopes, the 
  Santa Ana Mountains and inland Orange County. 

* WIND...Areas of northeast winds 20 to 30 mph with gusts 45 to 
  55 mph. Isolated gusts 60 to 65 mph below the Cajon and San 
  Gorgonio Passes, and near the coastal foothills of the Santa 
  Ana Mountains.

* HUMIDITY...Lowest humidity of 5 to 10 percent Sunday 
  afternoon.

* TIMING...Winds strengthen Saturday night, peak early Sunday
  morning then begin to weaken Sunday afternoon. Relative humidity
  begins to decrease late Sunday Morning with only marginal
  recovery expected Sunday night.

* IMPACTS...Any fires that develop will likely spread rapidly. 
  Outdoor burning is not recommended.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Red Flag Warning means that critical fire weather conditions
are either occurring now....or will shortly. A combination of
strong winds...low relative humidity...and warm temperatures can
contribute to extreme fire behavior.

&&

$$

jmb
327 
WWUS86 KSGX 201100
RFWSGX

URGENT - FIRE WEATHER MESSAGE
National Weather Service San Diego CA
300 AM PST Sat Nov 20 2021

CAZ248-255>257-265-554-202100-
/O.CON.KSGX.FW.W.0003.211121T1700Z-211122T0300Z/
San Bernardino and Riverside County Valleys - The Inland Empire-
San Bernardino County Mountains-
Including The Mountain Top And Front Country Ranger Districts Of
The San Bernardino National Forest-Riverside County Mountains-
Including The San Jacinto Ranger District Of The San Bernardino
National Forest-Santa Ana Mountains-
Including The Trabuco Ranger District of the Cleveland National
Forest-San Gorgonio Pass Near Banning-Orange County Inland Areas-
300 AM PST Sat Nov 20 2021

...RED FLAG WARNING REMAINS IN EFFECT FROM 9 AM TO 7 PM SUNDAY 
FOR STRONG GUSTY WINDS AND LOW HUMIDITY...

* LOCATION...Portions of the Inland Empire, the San Bernardino 
  mountain slopes, the Riverside County mountain slopes, the 
  Santa Ana Mountains and inland Orange County. 

* WIND...Areas of northeast winds 20 to 30 mph with gusts 45 to 
  55 mph. Isolated gusts 60 to 65 mph below the Cajon and San 
  Gorgonio Passes, and near the coastal foothills of the Santa 
  Ana Mountains.

* HUMIDITY...Lowest humidity of 5 to 10 percent Sunday 
  afternoon.

* TIMING...Winds strengthen tonight, peak Sunday morning then
  begin to weaken Sunday afternoon. Relative humidity begins to
  decrease late Sunday morning with only marginal recovery Sunday
  night.

* IMPACTS...Any fires that develop will likely spread rapidly. 
  Outdoor burning is not recommended.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Red Flag Warning means that critical fire weather conditions
are either occurring now....or will shortly. A combination of
strong winds...low relative humidity...and warm temperatures can
contribute to extreme fire behavior.

&&

$$

Moede
543 
WWUS86 KSGX 202109
RFWSGX

URGENT - FIRE WEATHER MESSAGE
National Weather Service San Diego CA
109 PM PST Sat Nov 20 2021

CAZ248-255>257-265-554-210600-
/O.CON.KSGX.FW.W.0003.211121T1700Z-211122T0300Z/
San Bernardino and Riverside County Valleys - The Inland Empire-
San Bernardino County Mountains-
Including The Mountain Top And Front Country Ranger Districts Of
The San Bernardino National Forest-Riverside County Mountains-
Including The San Jacinto Ranger District Of The San Bernardino
National Forest-Santa Ana Mountains-
Including The Trabuco Ranger District of the Cleveland National
Forest-San Gorgonio Pass Near Banning-Orange County Inland Areas-
109 PM PST Sat Nov 20 2021

...RED FLAG WARNING REMAINS IN EFFECT FROM 9 AM TO 7 PM PST
SUNDAY FOR STRONG GUSTY WINDS AND LOW HUMIDITY...

* LOCATION...Portions of the Inland Empire, the San Bernardino 
  mountain slopes, the Riverside County mountain slopes, the 
  Santa Ana Mountains and inland Orange County. 

* WIND...Areas of northeast winds 20 to 30 mph with gusts 45 to 
  55 mph. Isolated gusts 60 to 65 mph below the Cajon and San 
  Gorgonio Passes, and near the coastal foothills of the Santa 
  Ana Mountains.

* HUMIDITY...Lowest humidity of 5 to 10 percent Sunday 
  afternoon.

* TIMING...Winds strengthen tonight, peak Sunday morning then 
  begin to weaken Sunday afternoon. Relative humidity begins to 
  decrease late Sunday morning with only marginal recovery 
  Sunday night.

* IMPACTS...Any fires that develop will likely spread rapidly. 
  Outdoor burning is not recommended.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Red Flag Warning means that critical fire weather conditions
are either occurring now....or will shortly. A combination of
strong winds...low relative humidity...and warm temperatures can
contribute to extreme fire behavior.

&&

$$
371 
WWUS86 KSGX 210425
RFWSGX

URGENT - FIRE WEATHER MESSAGE
National Weather Service San Diego CA
825 PM PST Sat Nov 20 2021

CAZ248-255>257-265-554-211400-
/O.CON.KSGX.FW.W.0003.211121T1700Z-211122T0300Z/
San Bernardino and Riverside County Valleys - The Inland Empire-
San Bernardino County Mountains-
Including The Mountain Top And Front Country Ranger Districts Of
The San Bernardino National Forest-Riverside County Mountains-
Including The San Jacinto Ranger District Of The San Bernardino
National Forest-Santa Ana Mountains-
Including The Trabuco Ranger District of the Cleveland National
Forest-San Gorgonio Pass Near Banning-Orange County Inland Areas-
825 PM PST Sat Nov 20 2021

...RED FLAG WARNING REMAINS IN EFFECT FROM 9 AM TO 7 PM PST
SUNDAY FOR STRONG GUSTY WINDS AND LOW HUMIDITY...

* LOCATION...Portions of the Inland Empire, the San Bernardino 
  mountain slopes, the Riverside County mountain slopes, the 
  Santa Ana Mountains and inland Orange County. 

* WIND...Areas of northeast winds 20 to 30 mph with gusts 45 to 
  55 mph. Isolated gusts 60 to 65 mph below the Cajon and San 
  Gorgonio Passes, and near the coastal foothills of the Santa 
  Ana Mountains.

* HUMIDITY...Lowest humidity of 5 to 10 percent Sunday 
  afternoon.

* TIMING...Winds strengthen tonight, peak Sunday morning then 
  begin to weaken Sunday afternoon. Relative humidity begins to 
  decrease late Sunday morning with only marginal recovery 
  Sunday night.

* IMPACTS...Any fires that develop will likely spread rapidly. 
  Outdoor burning is not recommended.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Red Flag Warning means that critical fire weather conditions
are either occurring now....or will shortly. A combination of
strong winds...low relative humidity...and heat, can contribute 
to extreme fire behavior.

&&

$$
153 
WWUS86 KSGX 211248
RFWSGX

URGENT - FIRE WEATHER MESSAGE
National Weather Service San Diego CA
448 AM PST Sun Nov 21 2021

CAZ248-255>257-265-554-212130-
/O.CON.KSGX.FW.W.0003.211121T1700Z-211122T0300Z/
San Bernardino and Riverside County Valleys - The Inland Empire-
San Bernardino County Mountains-
Including The Mountain Top And Front Country Ranger Districts Of
The San Bernardino National Forest-Riverside County Mountains-
Including The San Jacinto Ranger District Of The San Bernardino
National Forest-Santa Ana Mountains-
Including The Trabuco Ranger District of the Cleveland National
Forest-San Gorgonio Pass Near Banning-Orange County Inland Areas-
448 AM PST Sun Nov 21 2021

...RED FLAG WARNING REMAINS IN EFFECT FROM 9 AM TO 7 PM TODAY FOR
STRONG GUSTY WINDS AND LOW HUMIDITY...

* LOCATION...Portions of the Inland Empire, the San Bernardino 
  mountain slopes, the Riverside County mountain slopes, the 
  Santa Ana Mountains and inland Orange County. 

* WIND...Areas of northeast winds 20 to 30 mph with gusts 45 to 55
  mph. Isolated gusts 60 to 65 mph below the Cajon and San
  Gorgonio Passes, and near the foothills of the Santa Ana 
  Mountains.

* HUMIDITY...Lowest humidity of 10 percent this afternoon.

* TIMING...Winds will peak this morning, then begin to weaken this
  afternoon and evening. Relative humidity falls through the
  afternoon with only marginal recovery tonight and Monday.

* IMPACTS...Any fires that develop will likely spread rapidly. 
  Outdoor burning is not recommended.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Red Flag Warning means that critical fire weather conditions
are either occurring now....or will shortly. A combination of
strong winds...low relative humidity...and heat, can contribute
to extreme fire behavior.

&&

$$

Moede
718 
WWUS86 KSGX 212049
RFWSGX

URGENT - FIRE WEATHER MESSAGE
National Weather Service San Diego CA
1249 PM PST Sun Nov 21 2021

CAZ248-255>257-265-554-220300-
/O.CON.KSGX.FW.W.0003.000000T0000Z-211122T0300Z/
San Bernardino and Riverside County Valleys - The Inland Empire-
San Bernardino County Mountains-
Including The Mountain Top And Front Country Ranger Districts Of
The San Bernardino National Forest-Riverside County Mountains-
Including The San Jacinto Ranger District Of The San Bernardino
National Forest-Santa Ana Mountains-
Including The Trabuco Ranger District of the Cleveland National
Forest-San Gorgonio Pass Near Banning-Orange County Inland Areas-
1249 PM PST Sun Nov 21 2021

...RED FLAG WARNING REMAINS IN EFFECT UNTIL 7 PM PST THIS EVENING
FOR STRONG GUSTY WINDS AND LOW HUMIDITY FOR PORTIONS OF THE SAN
BERNARDINO MOUNTAINS, RIVERSIDE COUNTY MOUNTAINS, SANTA ANA
MOUNTAINS, THE INLAND EMPIRE, INLAND ORANGE COUNTY, AND THE SAN
GORGONIO PASS...

* LOCATION...Portions of the Inland Empire, the San Bernardino
  coastal slopes and foothills, the Riverside County coastal
  slopes and foothills, the Santa Ana Mountains, and inland 
  Orange County.
 
* WIND...Areas of northeast to east winds 20 to 30 mph with gusts
  40 to 50 mph. Isolated gusts to 55 mph below the Cajon and San
  Gorgonio Passes, and in the favored canyons of the Santa Ana 
  Mountains.

* HUMIDITY...Lowest humidity of 10-15 percent this afternoon. Poor
  recovery tonight in the wind prone locations.

* TIMING...Winds will continue to weaken this afternoon into
  tonight. Dry conditions continuing into Monday.

* IMPACTS...Any fires that develop will likely spread rapidly. 
  Outdoor burning is not recommended.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Red Flag Warning means that critical fire weather conditions
are either occurring now....or will shortly. A combination of
strong winds...low relative humidity...and heat, can contribute
to extreme fire behavior.

&&

$$

SS
146 
WWUS86 KSGX 220253
RFWSGX

URGENT - FIRE WEATHER MESSAGE
National Weather Service San Diego CA
653 PM PST Sun Nov 21 2021

CAZ248-255>257-265-554-220400-
/O.EXP.KSGX.FW.W.0003.000000T0000Z-211122T0300Z/
San Bernardino and Riverside County Valleys - The Inland Empire-
San Bernardino County Mountains-
Including The Mountain Top And Front Country Ranger Districts Of
The San Bernardino National Forest-Riverside County Mountains-
Including The San Jacinto Ranger District Of The San Bernardino
National Forest-Santa Ana Mountains-
Including The Trabuco Ranger District of the Cleveland National
Forest-San Gorgonio Pass Near Banning-Orange County Inland Areas-
653 PM PST Sun Nov 21 2021

...RED FLAG WARNING WILL EXPIRE AT 7 PM PST THIS EVENING FOR
STRONG GUSTY WINDS AND LOW HUMIDITY.

Locally strong winds below passes and some canyons will continue
elevated fire weather conditions overnight into Monday, but
critical fire weather conditions are no longer expected for any
length of time.

$$

10

The office that day

Everything else NWS San Diego, CA issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Nov 19, 4:00 AM PSTDense Fog AdvisorySGXRiverside, San Bernardino, San Diego5 hr
Nov 19, 10:48 AM PSTFire Weather WatchSGXOrange, Riverside, San Bernardino, San Diego3 hr

Nearby

Red Flag Warnings in California, 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.