Alert archive / Oregon / Red Flag Warnings in 2021

Red Flag Warning 45, NWS Medford, OR

August 29, 2021Harney County, Klamath County, Lake County, Oregon; Modoc County, California

NWS Medford, OR issued this red flag warning at Aug 29, 2021, 3:44 AM PDT for Harney County, Klamath County, Lake County, Oregon; Modoc County, California. It took effect at Aug 30, 2021, 2:00 PM PDT. It was in force for 6 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 29, 2021, 3:44 AM PDT (10:44 UTC)
In effect from
Aug 30, 2021, 2:00 PM PDT
Expired
Aug 30, 2021, 8:00 PM PDT
In force
6 hr
Issued by
NWS Medford, OR

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

The radar

The Medford radar (KMAX), 194 km from the middle of the area, began a volume at 10:51 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 00:00Z, 10.7 hours before the alert went out and 195 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 00:00Z on 2021-08-29Temperature 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 00:00Z on 2021-08-29The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -4 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
3689 m above ground
0-6 km bulk shear
16 kt
0-1 km storm-relative helicity
-4 m²/s²
0-3 km storm-relative helicity
10 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

648 
WWUS86 KMFR 291044
RFWMFR

URGENT - FIRE WEATHER MESSAGE
National Weather Service Medford OR
344 AM PDT Sun Aug 29 2021

...Gusty Winds With Low Relative Humidity Sunday and Monday 
Afternoons and Evenings...

.Dry and unstable conditions are expected to develop this afternoon
and evening east of the Cascades as a thermal trough moves across 
the area. This will bring breezy conditions along with very low 
relative humidities to portions of the area east of the Cascades. 
This will be followed by a dry cold front tonight into Monday that
will bring stronger, gusty winds and low RHs to a larger area east
of the Cascades Monday afternoon and evening.

CAZ285-ORZ624-292245-
/O.UPG.KMFR.FW.A.0032.210830T2100Z-210831T0300Z/
/O.NEW.KMFR.FW.W.0045.210830T2100Z-210831T0300Z/
/O.CON.KMFR.FW.W.0044.210829T2100Z-210830T0300Z/
Modoc County Except for the Surprise Valley-
Klamath Basin and the Fremont-Winema National Forest-
344 AM PDT Sun Aug 29 2021

...RED FLAG WARNING REMAINS IN EFFECT FROM 2 PM THIS AFTERNOON TO
8 PM PDT THIS EVENING FOR STRONG GUSTY WIND WITH LOW RH FOR FIRE
WEATHER ZONES 285 AND 624...
...RED FLAG WARNING IN EFFECT FROM 2 PM TO 8 PM PDT MONDAY FOR
STRONG GUSTY WIND WITH LOW RH FOR FIRE WEATHER ZONES 285 AND 624...

The National Weather Service in Medford has issued a Red Flag
Warning...which is in effect from 2 PM to 8 PM PDT Monday. The
Fire Weather Watch is no longer in effect.

* Impacts: Strong, gusty wind with low relative humidity and 
  critically dry vegetation will greatly increase the spread 
  potential of any new and existing fires.

* Affected area: In Northern CA...Most of FWZ 285. In South 
  Central OR...Much of Fire Zone 624. For Sunday, the Red Flag 
  Warning is for areas east of Highway 97. For Monday, the Red Flag
  Warning includes areas east of Keno and areas east of Highway 97
  from about Modoc Point northward.

* Wind: Today, southwest through northwest winds 10 to 20 mph with
  gusts 20 to 30 mph. On Monday, southwest through northwest winds
  15 to 25 mph with gusts 25 to 35 mph.

* Minimum Relative Humidity: 8 to 14 percent.

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

* Humidity: As low as 9 percent.

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

Precautionary/preparedness actions...

Avoid tossing burning cigarettes on the ground, parking hot
vehicles on dry vegetation, and using equipment that can cause
sparks. Follow all fire restrictions. Find links to restrictions
at weather.gov/medford/wildfire. One less spark, one less
wildfire.

Gather your fire evacuation kit now. Collect essentials you don't
want to lose and prioritize your checklist. Visit ready.gov/kit
for more information.

Familiarize yourself with your evacuation plan. Where will you go?
How will you get there? Who will you call to let others know your
are safe? Visit ready.gov/wildfires for more information.

A Red Flag Warning does not mean there is a fire. It means that
critical fire weather conditions are either occurring now or will
shortly. These conditions promote rapid spread of fire which may
become life threatening. Evacuate if ordered to, or if a fire
threatens.

&&

$$

ORZ625-292245-
/O.UPG.KMFR.FW.A.0032.210830T2100Z-210831T0300Z/
/O.NEW.KMFR.FW.W.0045.210830T2100Z-210831T0300Z/
South Central Oregon Desert including the BLM Land in Eastern Lake
and Western Harney Counties-
344 AM PDT Sun Aug 29 2021

...RED FLAG WARNING IN EFFECT FROM 2 PM TO 8 PM PDT MONDAY FOR
STRONG GUSTY WIND WITH LOW RH FOR FIRE WEATHER ZONE 625...

The National Weather Service in Medford has issued a Red Flag
Warning...which is in effect from 2 PM to 8 PM PDT Monday. The
Fire Weather Watch is no longer in effect.

* Impacts: Strong, gusty wind with low relative humidity and 
  critically dry vegetation will greatly increase the spread 
  potential of any new and existing fires.

* Affected area: In South Central OR...All except the far northern
  portion of Fire Weather Zone 625.

* Wind: West 20 to 25 mph with gusts 30 to 40 mph.

* Minimum Relative Humidity: 7 to 14 percent.

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

* Humidity: As low as 7 percent.

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

Precautionary/preparedness actions...

Avoid tossing burning cigarettes on the ground, parking hot
vehicles on dry vegetation, and using equipment that can cause
sparks. Follow all fire restrictions. Find links to restrictions
at weather.gov/medford/wildfire. One less spark, one less
wildfire.

Gather your fire evacuation kit now. Collect essentials you don't
want to lose and prioritize your checklist. Visit ready.gov/kit
for more information.

Familiarize yourself with your evacuation plan. Where will you go?
How will you get there? Who will you call to let others know your
are safe? Visit ready.gov/wildfires for more information.

A Red Flag Warning does not mean there is a fire. It means that
critical fire weather conditions are either occurring now or will
shortly. These conditions promote rapid spread of fire which may
become life threatening. Evacuate if ordered to, or if a fire
threatens.

&&

$$


Visit us at www.weather.gov/Medford
3 follow-up statements
278 
WWUS86 KMFR 292058
RFWMFR

URGENT - FIRE WEATHER MESSAGE
National Weather Service Medford OR
158 PM PDT Sun Aug 29 2021

...Gusty Winds With Low Relative Humidity Today and Monday 
Afternoons and Evenings...

.Dry and unstable conditions are expected to develop this
afternoon and evening east of the Cascades as a thermal trough
moves across the area. This will bring breezy conditions along
with very low relative humidities to portions of the area east of
the Cascades. This will be followed by a dry cold front tonight
into Monday that will bring stronger, gusty winds and low RHs to a
larger area east of the Cascades Monday afternoon and evening.

CAZ285-ORZ624-300700-
/O.CON.KMFR.FW.W.0044.210829T2100Z-210830T0300Z/
/O.CON.KMFR.FW.W.0045.210830T2100Z-210831T0300Z/
Modoc County Except for the Surprise Valley-
Klamath Basin and the Fremont-Winema National Forest-
158 PM PDT Sun Aug 29 2021

...RED FLAG WARNING REMAINS IN EFFECT UNTIL 8 PM PDT THIS EVENING
FOR STRONG GUSTY WIND WITH LOW RH FOR FIRE WEATHER ZONES 285 AND
624...

...RED FLAG WARNING REMAINS IN EFFECT FROM 2 PM TO 8 PM PDT MONDAY
FOR STRONG GUSTY WIND WITH LOW RH FOR FIRE WEATHER ZONES 285 AND
624...

* Impacts: Strong, gusty wind with low relative humidity and
  critically dry vegetation will increase the spread potential of 
  any new and existing fires.

* Affected area: In Northern CA...Most of FWZ 285. In South Central
  OR...Much of Fire Zone 624. For today, the Red Flag Warning is 
  for areas east of Highway 97. For Monday, the Red Flag Warning 
  includes areas east of Keno and areas east of Highway 97 from 
  about Modoc Point northward.

* Wind: Today, southwest through northwest winds 10 to 15 mph with
  gusts 20 to 25 mph. On Monday, southwest through northwest winds
  10 to 20 mph with gusts 20 to 35 mph.

* Minimum Relative Humidity: 8 to 14 percent.

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

$$

ORZ625-300700-
/O.CON.KMFR.FW.W.0045.210830T2100Z-210831T0300Z/
South Central Oregon Desert including the BLM Land in Eastern Lake
and Western Harney Counties-
158 PM PDT Sun Aug 29 2021

...RED FLAG WARNING REMAINS IN EFFECT FROM 2 PM TO 8 PM PDT MONDAY
FOR STRONG GUSTY WIND WITH LOW RH FOR FIRE WEATHER ZONE 625...

* Impacts:  Strong, gusty wind with low relative humidity and
  critically dry vegetation will greatly increase the spread
  potential of any new and existing fires.

* Affected area: In South Central OR...All except the far northern
  portion of Fire Weather Zone 625.

* Wind: West 20 to 25 mph with gusts 30 to 35 mph.

* Minimum Relative Humidity: 7 to 14 percent.

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

$$
BTL

Visit us at www.weather.gov/Medford
638 
WWUS86 KMFR 300334
RFWMFR

URGENT - FIRE WEATHER MESSAGE
National Weather Service Medford OR
834 PM PDT Sun Aug 29 2021

...Gusty Winds With Low Relative Humidity Monday Afternoon and 
Evening...

.A dry cold front will move into the area tonight into Monday and 
will bring stronger, gusty winds and low RHs to a large area east 
of the Cascades Monday afternoon and evening.

CAZ285-ORZ624-625-310300-
/O.CON.KMFR.FW.W.0045.210830T2100Z-210831T0300Z/
Modoc County Except for the Surprise Valley-
Klamath Basin and the Fremont-Winema National Forest-
South Central Oregon Desert including the BLM Land in Eastern Lake
and Western Harney Counties-
834 PM PDT Sun Aug 29 2021

...RED FLAG WARNING REMAINS IN EFFECT FROM 2 PM TO 8 PM PDT MONDAY
FOR STRONG GUSTY WIND WITH LOW RH FOR FIRE WEATHER ZONES 285...
624 AND 625...

* Impacts:  Strong, gusty wind with low relative humidity and
critically dry vegetation will greatly increase the spread
potential of any new and existing fires.

* Affected area: 
  In Northern CA...Most of Fire Weather Zone 285. In South Central
  OR...Much of Fire Weather Zones 624 and 625. The Red Flag Warning 
  includes areas east of Keno and areas east of Highway 97 from 
  about Modoc Point northward.

* Wind: Southwest through northwest winds 10 to 20 mph with gusts 
  to 35 mph.

* Minimum Relative Humidity: 8 to 14 percent.

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

$$


Visit us at www.weather.gov/Medford
855 
WWUS86 KMFR 310253
RFWMFR

URGENT - FIRE WEATHER MESSAGE
National Weather Service Medford OR
753 PM PDT Mon Aug 30 2021



CAZ285-ORZ624-625-310400-
/O.EXP.KMFR.FW.W.0045.000000T0000Z-210831T0300Z/
Modoc County Except for the Surprise Valley-
Klamath Basin and the Fremont-Winema National Forest-
South Central Oregon Desert including the BLM Land in Eastern Lake
and Western Harney Counties-
753 PM PDT Mon Aug 30 2021

...RED FLAG WARNING WILL EXPIRE AT 8 PM PDT THIS EVENING FOR
STRONG GUSTY WIND WITH LOW RH FOR FIRE WEATHER ZONES 285...624 AND
625...

Winds are diminishing across the area.

$$


Visit us at www.weather.gov/Medford

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 29, 3:13 AM PDTHazardous Seas WarningMFR59 hr

Nearby

Red Flag Warnings in Oregon, 2021Red 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.