Alert archive / California / Red Flag Warnings in 2021

Red Flag Warning 1, NWS Medford, OR

May 13, 2021Modoc County, Siskiyou County, California; Klamath County, Lake County, Oregon

NWS Medford, OR issued this red flag warning at May 13, 2021, 2:22 PM PDT for Modoc County, Siskiyou County, California; Klamath County, Lake County, Oregon. It took effect at May 14, 2021, 2:00 PM PDT. It was in force for 7 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
May 13, 2021, 2:22 PM PDT (21:22 UTC)
In effect from
May 14, 2021, 2:00 PM PDT
Expired
May 14, 2021, 8:48 PM PDT
In force
7 hr
Issued by
NWS Medford, OR

Counties Modoc County, CA, Siskiyou County, CA, Klamath County, OR, Lake County, OR

The radar

The Medford radar (KMAX), 115 km from the middle of the area, began a volume at 21:24 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

Medford/Jackson, OR (KMFR), launched 12:00Z, 9.4 hours before the alert went out and 123 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, Medford/Jackson, OR at 12:00Z on 2021-05-13Temperature 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, Medford/Jackson, OR at 12:00Z on 2021-05-13The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 1 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
1914 m above ground
0-6 km bulk shear
21 kt
0-1 km storm-relative helicity
1 m²/s²
0-3 km storm-relative helicity
39 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

216 
WWUS86 KMFR 132122
RFWMFR

URGENT - FIRE WEATHER MESSAGE
National Weather Service Medford OR
222 PM PDT Thu May 13 2021

...Scattered thunderstorms on unseasonably dry fuels Friday
afternoon and evening...

.A low pressure system will bring scattered thunderstorms to the areas
east of the Cascades and over northern California Friday afternoon
and evening. The combination of abundant lightning and fuel 
conditions that are two to three weeks ahead of normal dryness will
make for increased threat of new fire starts.

CAZ281-282-284-285-ORZ624-141200-
/O.NEW.KMFR.FW.W.0001.210514T2100Z-210515T0600Z/
Central Siskiyou County Including Shasta Valley-Shasta-
Trinity National Forest in Siskiyou County-
Siskiyou County from the Cascade Mountains East and South to Mt
Shasta-Modoc County Except for the Surprise Valley-
Klamath Basin and the Fremont-Winema National Forest-
222 PM PDT Thu May 13 2021

...RED FLAG WARNING IN EFFECT FROM 2 PM TO 11 PM PDT FRIDAY FOR
ABUNDANT LIGHTNING ON DRY FUELS FOR FIRE WEATHER ZONES 281...282...
284...285 AND 624...

The National Weather Service in Medford has issued a Red Flag
Warning...which is in effect from 2 PM to 11 PM PDT Friday.

* Impacts: Lightning and moderate to high fire danger will likely 
  result in new fire starts. Gusty thunderstorm winds could 
  contribute to fire spread. Despite rainfall, initial attack 
  resources could be overwhelmed and holdover fires are possible.

* Affected area: 
  In Northern CA Fire Zones...281...282...284...285 which includes
  most of central and eastern Siskiyou County and the northwest  
  portion of Modoc County. 
  In South Central OR Fire Zone....624 which includes the majority 
  of Klamath County and the western fringes of Lake County.

* Wind: Northwest 5 to 10 mph except erratic wind gusts to 40 mph 
  near any thunderstorms.

* Thunderstorms: Isolated to scattered. 

* Rainfall: Storms will produce some rainfall, but wetting rains
  are not expected. 

* View the hazard area in detail at:
  https://www.wrh.noaa.gov/mfr/HAZARD 

Precautionary/preparedness actions...

A Red Flag Warning means that critical fire weather conditions are
either occurring now, or will shortly. Scattered thunderstorms
combined with dry fuels create conditions where many fire starts
may occur in a short period of time. 

&&

$$


Visit us at www.weather.gov/Medford
3 follow-up statements
019 
WWUS86 KMFR 141135
RFWMFR

URGENT - FIRE WEATHER MESSAGE
National Weather Service Medford OR
435 AM PDT Fri May 14 2021

...Scattered thunderstorms on unseasonably dry fuels this afternoon
and evening...

.A low pressure system will bring scattered thunderstorms to the
areas east of the Cascades and over northern California this
afternoon and evening. The combination of abundant lightning and 
fuel conditions that are two to three weeks ahead of normal dryness
will make for increased threat of new fire starts.

CAZ281-282-284-285-ORZ624-142345-
/O.CON.KMFR.FW.W.0001.210514T2100Z-210515T0600Z/
Central Siskiyou County Including Shasta Valley-Shasta-
Trinity National Forest in Siskiyou County-
Siskiyou County from the Cascade Mountains East and South to Mt
Shasta-Modoc County Except for the Surprise Valley-
Klamath Basin and the Fremont-Winema National Forest-
435 AM PDT Fri May 14 2021

...RED FLAG WARNING REMAINS IN EFFECT FROM 2 PM THIS AFTERNOON TO
11 PM PDT THIS EVENING FOR ABUNDANT LIGHTNING ON DRY FUELS FOR
FIRE WEATHER ZONES 281...282...284...285 AND 624...

The National Weather Service in Medford has issued a Red Flag
Warning...which is in effect from 2 PM to 11 PM PDT Friday.

* Impacts:  Lightning and high fire danger will likely result in
new fire starts. Gusty thunderstorm winds could contribute to fire
spread. Despite rainfall, initial attack resources could be
overwhelmed and holdover fires are possible.

* Affected area: 
  In Northern CA Fire Zones...281...282...284...285 which includes
  most of central and eastern Siskiyou County and the northwest  
  portion of Modoc County. 
  In South Central OR Fire Zone....624 which includes the majority 
  of Klamath County and the western fringes of Lake County.

* Wind: Northwest 5 to 10 mph except erratic wind gusts to 40 mph
near any thunderstorms.

* Thunderstorms: Isolated to scattered.

* Rainfall: Storms will produce some rainfall, but wetting rains
are not expected.

* View the hazard area in detail at:
https://www.wrh.noaa.gov/mfr/HAZARD

Precautionary/preparedness actions...

A Red Flag Warning means that critical fire weather conditions are
either occurring now, or will shortly. Scattered thunderstorms
combined with dry fuels create conditions where many fire starts
may occur in a short period of time. 

$$


Visit us at www.weather.gov/Medford
086 
WWUS86 KMFR 142026
RFWMFR

URGENT - FIRE WEATHER MESSAGE
National Weather Service Medford OR
126 PM PDT Fri May 14 2021

...Scattered thunderstorms on unseasonably dry fuels this
afternoon and evening...

.A low pressure system will bring scattered thunderstorms to 
areas east of the Cascades and over northern California this 
afternoon and evening. The combination of abundant lightning and 
fuel conditions that are two to three weeks ahead of normal dryness
will make for increased threat of new fire starts.

CAZ281-282-284-285-ORZ624-150600-
/O.CON.KMFR.FW.W.0001.210514T2100Z-210515T0600Z/
Central Siskiyou County Including Shasta Valley-Shasta-
Trinity National Forest in Siskiyou County-
Siskiyou County from the Cascade Mountains East and South to Mt
Shasta-Modoc County Except for the Surprise Valley-
Klamath Basin and the Fremont-Winema National Forest-
126 PM PDT Fri May 14 2021

...RED FLAG WARNING REMAINS IN EFFECT UNTIL 11 PM PDT THIS EVENING
FOR ABUNDANT LIGHTNING ON DRY FUELS FOR FIRE WEATHER ZONES 281...
282...284...285 AND 624...

* Impacts: Lightning and high fire danger will likely result in new
  fire starts. Gusty thunderstorm winds could contribute to fire 
  spread. Despite rainfall, initial attack resources could be 
  overwhelmed and holdover fires are possible.

* Affected area: 
  In Northern CA Fire Zones...281...282...284...285, including most
  of central and eastern Siskiyou County and the northwest portion 
  of Modoc County. 
  In South Central OR Fire Zone 624, including the majority of 
  Klamath County and the western fringes of Lake County.

* Wind: Northwest 5 to 10 mph except erratic wind gusts to 40 mph
  near any thunderstorms.

* Thunderstorms: Isolated to scattered.

* Rainfall: Storms will produce some rainfall, but wetting rains
  are not likely.

* View the hazard area in detail at:
  https://www.wrh.noaa.gov/mfr/HAZARD

$$


Visit us at www.weather.gov/Medford
771 
WWUS86 KMFR 150348
RFWMFR

URGENT - FIRE WEATHER MESSAGE
National Weather Service Medford OR
848 PM PDT Fri May 14 2021


CAZ281-282-284-285-ORZ624-150500-
/O.CAN.KMFR.FW.W.0001.000000T0000Z-210515T0600Z/
Central Siskiyou County Including Shasta Valley-Shasta-
Trinity National Forest in Siskiyou County-
Siskiyou County from the Cascade Mountains East and South to Mt
Shasta-Modoc County Except for the Surprise Valley-
Klamath Basin and the Fremont-Winema National Forest-
848 PM PDT Fri May 14 2021

...RED FLAG WARNING IS CANCELLED FOR ABUNDANT LIGHTNING ON DRY
FUELS FOR FIRE WEATHER ZONES 281...282...284...285 AND 624...

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

The chance for thunderstorms has largely subsided. One or two
isolated storms will be possible for the western portion of zones 
281 and 282 for the next half hour, but these storms are drifting 
out of these areas quickly. 

$$


Visit us at www.weather.gov/Medford

The office that day

Everything else NWS Medford, OR issued on the same UTC day.

IssuedProductOfficeCountiesLasted
May 13, 2:52 PM PDTGale WarningMFR60 hr

Nearby

Red Flag Warnings in California, 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.