Alert archive / California / Red Flag Warnings in 2026

Red Flag Warning 1, NWS San Diego, CA

June 23, 2026San Bernardino County, California

NWS San Diego, CA issued this red flag warning at Jun 23, 2026, 10:28 AM PDT for San Bernardino County, California. It took effect at Jun 23, 2026, 5:00 PM PDT. It was in force for 18 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
Jun 23, 2026, 10:28 AM PDT (17:28 UTC)
In effect from
Jun 23, 2026, 5:00 PM PDT
Expired
Jun 24, 2026, 11:00 AM PDT
In force
18 hr
Issued by
NWS San Diego, CA

County San Bernardino County, CA

The radar

The Edwards AFB radar (KEYX), 129 km from the middle of the area, began a volume at 17:33 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

Las Vegas, NV (KVEF), launched 12:00Z, 5.5 hours before the alert went out and 180 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, Las Vegas, NV at 12:00Z on 2026-06-23Temperature 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°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Las Vegas, NV at 12:00Z on 2026-06-23The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 84 square meters per square second.1939Sfc1 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
5359 m above ground
0-6 km bulk shear
21 kt
0-1 km storm-relative helicity
84 m²/s²
0-3 km storm-relative helicity
114 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

165 
WWUS86 KSGX 231728
RFWSGX

URGENT - FIRE WEATHER MESSAGE
National Weather Service San Diego CA
1028 AM PDT Tue Jun 23 2026


CAZ260-240515-
/O.NEW.KSGX.FW.W.0001.260624T0000Z-260624T1800Z/
Victor Valley - Apple Valley - Lucerne Valley - Johnson Valley-
1028 AM PDT Tue Jun 23 2026

...RED FLAG WARNING IN EFFECT FROM 5 PM THIS AFTERNOON TO 11 AM
PDT WEDNESDAY FOR DRY LIGHTNING AND GUSTY OUTFLOW WINDS FOR
PORTIONS OF THE MOJAVE DESERT NORTH AND EAST OF BIG BEAR...

The National Weather Service in San Diego has issued a Red Flag
Warning for dry lightning and gusty outflow winds, which is in
effect from 5 PM this afternoon to 11 AM PDT Wednesday.

* IMPACTS...Dry lightning strikes could produce fire starts and
  any fires that develop could spread rapidly.

* LOCATION...Victor Valley  -Apple Valley  -Lucerne Valley  -
  Johnson Valley.

* THUNDERSTORMS...Isolated to scattered elevated thunderstorms
  will have the potential to produce lightning strikes with little
  or no rainfall.

* OUTFLOW WINDS...Gusty and erratic outflow winds will also be
  possible in and near any storms that develop.

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.

&&

$$

http://www.weather.gov/sandiego
2 follow-up statements
346 
WWUS86 KSGX 241041
RFWSGX

URGENT - FIRE WEATHER MESSAGE
National Weather Service San Diego CA
341 AM PDT Wed Jun 24 2026

CAZ260-241800-
/O.CON.KSGX.FW.W.0001.000000T0000Z-260624T1800Z/
Victor Valley-Apple Valley-Lucerne Valley-Johnson Valley-
341 AM PDT Wed Jun 24 2026

...RED FLAG WARNING REMAINS IN EFFECT UNTIL 11 AM PDT THIS
MORNING FOR DRY LIGHTNING AND GUSTY OUTFLOW WINDS FOR PORTIONS OF
THE MOJAVE DESERT NORTH AND EAST OF BIG BEAR...

* IMPACTS...Dry lightning strikes could produce fire starts and 
  any fires that develop could spread rapidly.

* LOCATION...Victor Valley-Apple Valley-Lucerne Valley-Johnson 
  Valley.

* THUNDERSTORMS...Isolated to scattered elevated thunderstorms 
  will have the potential to produce lightning strikes with 
  little or no rainfall.

* OUTFLOW WINDS...Gusty and erratic outflow winds will also be 
  possible in and near any storms that develop.

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.

&&

$$

17

http://www.weather.gov/sandiego
848 
WWUS86 KSGX 241759
RFWSGX

URGENT - FIRE WEATHER MESSAGE
National Weather Service San Diego CA
1059 AM PDT Wed Jun 24 2026

CAZ260-241900-
/O.EXP.KSGX.FW.W.0001.000000T0000Z-260624T1800Z/
Victor Valley-Apple Valley-Lucerne Valley-Johnson Valley-
1059 AM PDT Wed Jun 24 2026

...RED FLAG WARNING WILL EXPIRE AT 11 AM PDT THIS MORNING FOR DRY
LIGHTNING AND GUSTY OUTFLOW WINDS FOR PORTIONS OF THE MOJAVE 
DESERT NORTH AND EAST OF BIG BEAR...

Mid level moisture and an upper level disturbance that provided 
the risk for dry thunderstorms is departing to the northeast on 
schedule this morning. Thus, the Red Flag Warning will be allowed 
to expire as planned.

$$

http://www.weather.gov/sandiego

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 San Diego, CA wrote its last area forecast discussion before this red flag warning went out at Jun 23, 1:26 AM PDT, 9 hours 2 minutes earlier.

Area forecast discussion, Jun 23, 1:26 AM PDT, 9 hours 2 minutes before
Area Forecast Discussion
National Weather Service San Diego CA
126 AM PDT Tue Jun 23 2026

.SYNOPSIS...
Strengthening high pressure to the east will bring a warming trend
through Wednesday with moderate HeatRisk for the deserts. Mid
level moisture in southerly flow aloft will bring a slight chance
of showers and thunderstorms for this afternoon through Wednesday
afternoon for the mountains of San Bernardino and Riverside
Counties east and northeastward across the deserts of southern
California. This will be followed by a cooling trend for Thursday
through the weekend. Southwest to west winds for the mountains and
deserts will strengthen through Saturday with gusts on Saturday
to 30 to 40 mph with gusts to 65 mph in the northern Coachella
Valley below the San Gorgonio Pass.

&&

.DISCUSSION...FOR EXTREME SOUTHWESTERN CALIFORNIA INCLUDING ORANGE...
SAN DIEGO...WESTERN RIVERSIDE AND SOUTHWESTERN SAN BERNARDINO
COUNTIES...

.SHORT TERM (Today through Thursday)...
High pressure to the east will continue the warming trend today
with slight additional warming of high temperatures on Wednesday.
High temperatures on Wednesday will range from a few degrees above
average near the coast to 4 to 8 degrees above average inland.
High temperatures on Wednesday will range from the lower to mid
70s near the coast to the 90s for the Inland Empire with 108 to
112 for the lower deserts. Tonight will be much warmer as well
with low temperatures for early Wednesday mostly in the 80s for
the lower deserts. The marine layer will remain around 2000 feet
deep with night and morning coastal low clouds extending inland
into portions of the western valleys late each night.

Southerly flow between a weak upper level low pressure system off
the southern California coast and high pressure centered near El
Paso will allow some mid level moisture to be drawn northward into
portions of southern California into Wednesday. There is 20 to 30
percent chance for showers and thunderstorms for this afternoon
through Wednesday afternoon, mainly for the mountains of San
Bernardino and Riverside Counties northeastward across the Mojave
Desert. The ECMWF Extreme Forecast Index for precipitation has a
large shift of tails for tonight through Wednesday afternoon for
this area, most likely a reflection of a few relatively wetter
ensemble members during the climatologically driest time of the
year for portions of southern California.

&&

.LONG TERM (Friday through Monday)...
A low pressure system moving southward just off the coast of
British Columbia will strengthen the onshore slow across southern
California into the weekend. Southwest to west winds for the
mountains and deserts during the afternoon and evening will
strengthen for Thursday through Saturday with gusts on Saturday of
30 to 40 mph with gusts to 65 mph in the northern Coachella
Valley below the San Gorgonio Pass. The marine layer will deepen
with night and morning coastal low clouds spreading farther into
the valleys late each night.

There will be a cooling trend through the weekend with high
temperatures on Sunday as much as 15 degrees below average for
the mountains and inland valleys. High temperures on Sunday will
range from around 70 near the coast to mid 70s to lower 80s for
the Inland Empire with the mid 90s to 102 for the lower deserts.
High temperatures for Monday of next week will be a few degrees
warmer.

&&

.AVIATION...
230530Z...Coast/Valleys...Low clouds with bases 1000-1500ft MSL have
infiltrated the coastal areas and will continue to increase in
coverage and push inland, up to 15 miles, over the next few hours.
Bases are expected to lower 09-13Z up to a few hundred feet. Lower
visibilities of 3-6SM can be expected where clouds intersect
terrain. Clouds will scatter and retreat to the coast 15-18Z. Low
clouds return after 03Z Wednesday with similar bases.

Mountains/Deserts...VFR conditions expected through the TAF period
with periodic high clouds AOA 15000 ft MSL after 19Z.

&&

.MARINE...
No hazardous marine conditions are expected through Sunday.

&&

.BEACHES...
Surf will increase Tuesday through Thursday with the arrival of a 3
foot 15 to 18 second period south swell from 190 to 210 degrees.
Surf of 4 to 6 ft is expected. Expect locally hazardous swimming
conditions and strong rip currents through the week. Please see the
Beach Hazards Statement for more details.

&&

.FIRE WEATHER...
A low pressure system moving southward just off the coast of
British Columbia will strengthen the onshore slow across southern
California into the weekend. Southwest to west winds for the
mountains and deserts during the afternoon will strengthen for
Thursday through Saturday with gusts on Saturday of 30 to 40 mph
with gusts to 65 mph in the northern Coachella Valley below the
San Gorgonio Pass. Lowest humidity for the lower deserts will fall
to around 10 percent for Thursday afternoon and Friday afternoon with
near critical fire weather conditions for the deserts onto the
desert slopes of the mountains for Thursday and Friday afternoon
and early evening.

&&

.SKYWARN...
Skywarn activation is not requested. However weather spotters are
encouraged to report significant weather conditions.

&&

.SGX WATCHES/WARNINGS/ADVISORIES...
CA...Beach Hazards Statement from 11 AM PDT Tuesday through Thursday
     evening for Orange County Coastal Areas-San Diego County
     Coastal Areas.

PZ...None.

&&

PUBLIC/FIRE WEATHER...17
AVIATION/MARINE...Villafane

The office that day

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

IssuedProductOfficeCountiesLasted
Jun 23, 10:08 AM PDTExtreme Heat WarningSGXSan Diego58 hr

Nearby

Red Flag Warnings in California, 2026Every red flag warning in 2026

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.