Alert archive / Washington / Red Flag Warnings in 2017

Red Flag Warning 4, NWS Seattle, WA

September 3, 201711 counties in Washington

NWS Seattle, WA issued this red flag warning at Sep 3, 2017, 12:58 PM PDT for 11 counties in Washington. It took effect at Sep 3, 2017, 11:00 PM PDT. It was in force for 45 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
Sep 3, 2017, 12:58 PM PDT (19:58 UTC)
In effect from
Sep 3, 2017, 11:00 PM PDT
Expired
Sep 5, 2017, 8:00 PM PDT
In force
45 hr
Issued by
NWS Seattle, WA

Counties Clallam County, WA, Grays Harbor County, WA, Jefferson County, WA, King County, WA, Lewis County, WA, Mason County, WA, Pierce County, WA, Skagit County, WA, Skamania County, WA, Snohomish County, WA, Whatcom County, WA

The radar

The Seattle radar (KATX), 74 km from the middle of the area, began a volume at 20:01 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

Quillayute State, WA (KUIL), launched 12:00Z, 8.0 hours before the alert went out and 152 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, Quillayute State, WA at 12:00Z on 2017-09-03Temperature 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, Quillayute State, WA at 12:00Z on 2017-09-03The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -59 square meters per square second.193958Sfc1 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
1582 m above ground
0-6 km bulk shear
34 kt
0-1 km storm-relative helicity
-59 m²/s²
0-3 km storm-relative helicity
20 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

630 
WWUS86 KSEW 031958
RFWSEW

URGENT - FIRE WEATHER MESSAGE
National Weather Service Seattle WA
1258 PM PDT Sun Sep 3 2017

WAZ650-041545-
/O.UPG.KSEW.FW.A.0006.170904T1700Z-170905T2000Z/
/O.NEW.KSEW.FW.W.0004.170904T0600Z-170905T2000Z/
North Coastal Lowlands-
1258 PM PDT Sun Sep 3 2017

...RED FLAG WARNING IN EFFECT FROM 11 PM THIS EVENING TO 1 PM PDT
TUESDAY FOR WIND AND LOW HUMIDITY...

The National Weather Service in Seattle has issued a Red Flag
Warning, which is in effect from 11 PM this evening to 1 PM PDT
Tuesday. The Fire Weather Watch is no longer in effect. 

* WIND...Moderate East-Northeast breezes of 10 to 15 mph with
  gusts around 20 to 25 mph are expected to develop tonight and
  last at times into Tuesday morning. Strongest wind will be at
  higher exposed locations such as Ellis Mountain. Lower 
  elevations from the Sol Duc Basin northward could experience 
  gusty winds and low RH during the day on Monday.

* TEMPERATURES/HUMIDITY...Hot temperatures are forecast on Monday
  and Tuesday, with highs reaching the upper 80s. Relative
  humidity values of 20 to 35 percent are expected. Nighttime
  humidity recovery will be very poor tonight and Monday night
  above nighttime inversions.

* IMPACTS...Outdoor burning is not recommended. Any new fires
  could spread rapidly.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Red Flag Warning means that critical fire weather conditions 
are either occurring now, or will shortly. A combination of a 
moderate breeze, low relative humidity, and warm temperatures can
contribute to rapid rates of spread and downwind spotting on 
new and existing fires.

&&

$$

WAZ652-661-041545-
/O.UPG.KSEW.FW.A.0006.170904T1400Z-170906T0400Z/
/O.NEW.KSEW.FW.W.0004.170904T1400Z-170906T0300Z/
West Portion of the Olympic Mountains-
East Portion of the Olympic Mountains-
1258 PM PDT Sun Sep 3 2017

...RED FLAG WARNING IN EFFECT FROM 7 AM MONDAY TO 8 PM PDT 
TUESDAY FOR A DRY AND UNSTABLE AIR MASS...

The National Weather Service in Seattle has issued a Red Flag 
Warning, which is in effect from 7 AM Monday to 8 PM PDT Tuesday. 
The Fire Weather Watch is no longer in effect. 

* HAINES...Mid-Level Haines 6 conditions are forecast for Monday 
  and Tuesday. This indicates a dry and unstable air mass. 

* TEMPERATURES/HUMIDITY...Relative humidity will drop below 25 
  percent on Monday and Tuesday, with very poor nighttime humidity
  recovery from tonight through Tuesday night.

* IMPACTS...Outdoor burning is not recommended. Any new fires
  could spread rapidly.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Red Flag Warning means that critical fire weather conditions 
are either occurring now, or will shortly. A dry and unstable air 
mass with warm temperatures can contribute to active fire 
behavior. In western Washington, significant growth on existing 
fires takes place under such conditions.

&&

$$

WAZ658-659-041545-
/O.UPG.KSEW.FW.A.0006.170904T1900Z-170906T0400Z/
/O.NEW.KSEW.FW.W.0004.170904T1900Z-170906T0300Z/
West Slopes of the North Cascades Generally above 1500 Feet-
West Slopes of the Central Cascades Generally above 1500 Feet-
1258 PM PDT Sun Sep 3 2017

...RED FLAG WARNING IN EFFECT FROM NOON MONDAY TO 8 PM PDT 
TUESDAY FOR A DRY AND UNSTABLE AIR MASS ALONG WITH MODERATE EAST 
BREEZES...

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

* HAINES...Mid-Level Haines 6 conditions will develop on Monday 
  and continue through Tuesday. This indicates a dry and unstable 
  air mass. 

* TEMPERATURES/HUMIDITY...Hot afternoon temperatures are 
  expected, and will be much above normal for this time of year. 
  Relative humidity values will fall below 25 percent both Monday 
  and Tuesday afternoons. Very poor nighttime humidity recovery is
  expected from tonight through Tuesday night.

* WIND...East breezes of 10 to 15 mph with gusts around 25 to 30 
  mph are expected from Monday evening through Tuesday morning 
  through the Cascades, especially from Glacier Peak area on 
  south.

* IMPACTS...Outdoor burning is not recommended. Any new fires
  could spread rapidly.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Red Flag Warning means that critical fire weather conditions 
are either occurring now, or will shortly. A combination of a 
moderate breeze...low relative humidity...and warm temperatures 
can contribute to rapid rates of spread and downwind spotting on 
existing fires. A dry and unstable air mass with warm temperatures
can contribute to active fire behavior. In western Washington, 
significant growth on new and existing fires takes place under 
such conditions.

&&

$$

WAZ662-040300-
/O.CON.KSEW.FW.W.0003.000000T0000Z-170904T0300Z/
East Portion of North Cascades National Park/Lake Chelan National
Recreational Area-
1258 PM PDT Sun Sep 3 2017

...RED FLAG WARNING REMAINS IN EFFECT UNTIL 8 PM PDT THIS EVENING
FOR HOT...DRY AND UNSTABLE CONDITIONS FOR FIRE WEATHER ZONE 662...

* HAINES...Mid- and High-Level Haines Index values of 5 to 6, 
  indicating a dry and unstable air mass. 

* TEMPERATURES/HUMIDITY...High temperatures this afternoon will 
  climb into the mid 90s in Stehekin, with Minimum Relative 
  Humidity near 15 percent. 

* IMPACTS...These conditions will support active burning on new 
  and existing fires. Outdoor burning is not recommended.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Red Flag Warning means that critical fire weather conditions
are expected to occur. A dry and unstable air mass with warm
temperatures can contribute to active fire behavior. Significant
growth on new and existing fires takes place under such
conditions.

&&

$$

www.weather.gov/seattle
3 follow-up statements
201 
WWUS86 KSEW 041529
RFWSEW

URGENT - FIRE WEATHER MESSAGE
National Weather Service Seattle WA
829 AM PDT Mon Sep 4 2017

WAZ652-661-042330-
/O.CON.KSEW.FW.W.0004.000000T0000Z-170906T0300Z/
West Portion of the Olympic Mountains-
East Portion of the Olympic Mountains-
829 AM PDT Mon Sep 4 2017

...RED FLAG WARNING REMAINS IN EFFECT UNTIL 8 PM PDT TUESDAY FOR
A DRY AND UNSTABLE AIR MASS...

* HAINES...Mid-Level Haines 6 conditions are forecast for today 
  and Tuesday. This indicates a dry and unstable air mass. 

* TEMPERATURES/HUMIDITY...Relative humidity will drop below 25
  percent today and Tuesday, with very poor nighttime humidity
  recovery through Tuesday night. Temperatures will be much above
  normal for this time of year.

* IMPACTS...Outdoor burning is not recommended. Any new fires 
  could spread rapidly.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Red Flag Warning means that critical fire weather conditions
are either occurring now, or will shortly. A dry and unstable air
mass with warm temperatures can contribute to active fire
behavior. In western Washington, significant growth on existing
fires takes place under such conditions.

&&

$$

WAZ650-042330-
/O.CON.KSEW.FW.W.0004.000000T0000Z-170905T2000Z/
North Coastal Lowlands-
829 AM PDT Mon Sep 4 2017

...RED FLAG WARNING REMAINS IN EFFECT UNTIL 1 PM PDT TUESDAY FOR
WIND AND LOW HUMIDITY...

* WIND...Moderate East-Northeast breezes of 10 to 15 mph with
  gusts around 20 to 25 mph are expected to continue at times
  until Tuesday morning. Strongest wind will be at higher exposed
  locations such as Ellis Mountain. Lower elevations from the Sol
  Duc Basin northward could experience gusty winds and low RH this
  afternoon. 

* TEMPERATURES/HUMIDITY...Hot temperatures are expected today and
  Tuesday, with highs reaching the upper 80s and lower 90s. This
  is much above normal for this time of year. Relative humidity 
  values of 20 to 35 percent are expected. Nighttime humidity 
  recovery will be very poor tonight above low- lying nighttime 
  inversions.

* IMPACTS...Outdoor burning is not recommended. Any new fires 
  could spread rapidly.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Red Flag Warning means that critical fire weather conditions
are either occurring now, or will shortly. A combination of a
moderate breeze, low relative humidity, and warm temperatures can
contribute to rapid rates of spread and downwind spotting on new
and existing fires.

&&

$$

WAZ658-659-042330-
/O.CON.KSEW.FW.W.0004.170904T1900Z-170906T0300Z/
West Slopes of the North Cascades Generally above 1500 Feet-
West Slopes of the Central Cascades Generally above 1500 Feet-
829 AM PDT Mon Sep 4 2017

...RED FLAG WARNING REMAINS IN EFFECT FROM NOON TODAY TO 8 PM PDT
TUESDAY FOR A DRY AND UNSTABLE AIR MASS ALONG WITH MODERATE EAST
BREEZES...

* HAINES...Mid-Level Haines 6 conditions will develop today and 
  continue through Tuesday. This indicates a dry and unstable air 
  mass. 

* TEMPERATURES/HUMIDITY...Hot afternoon temperatures are 
  expected, and will be much above normal for this time of 
  year. Relative humidity values will fall below 25 percent 
  both Monday and Tuesday afternoons. Very poor nighttime 
  humidity recovery is expected from tonight through Tuesday 
  night. 

* WIND...East breezes of 10 to 15 mph with gusts around 25 to 
  30 mph are expected from Monday evening through Tuesday 
  morning through the Cascades, especially from Glacier Peak 
  area on south.

* IMPACTS...Outdoor burning is not recommended. Any new fires 
  could spread rapidly.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Red Flag Warning means that critical fire weather conditions
are either occurring now, or will shortly. A combination of a
moderate breeze...low relative humidity...and warm temperatures
can contribute to rapid rates of spread and downwind spotting on
existing fires. A dry and unstable air mass with warm
temperatures can contribute to active fire behavior. In western
Washington, significant growth on new and existing fires takes
place under such conditions.

&&

$$


www.weather.gov/seattle
228 
WWUS86 KSEW 042246
RFWSEW

URGENT - FIRE WEATHER MESSAGE
National Weather Service Seattle WA
346 PM PDT Mon Sep 4 2017

WAZ652-658-659-661-051600-
/O.CON.KSEW.FW.W.0004.000000T0000Z-170906T0300Z/
West Portion of the Olympic Mountains-
West Slopes of the North Cascades Generally above 1500 Feet-
West Slopes of the Central Cascades Generally above 1500 Feet-
East Portion of the Olympic Mountains-
346 PM PDT Mon Sep 4 2017

...RED FLAG WARNING REMAINS IN EFFECT UNTIL 8 PM PDT TUESDAY FOR
A DRY AND UNSTABLE AIR MASS...

* HAINES...Mid-Level Haines 6 conditions are forecast through 
  Tuesday. This indicates a dry and unstable air mass. 

* TEMPERATURES/HUMIDITY...Relative humidity will drop below 25
  percent Tuesday, with very poor nighttime humidity recovery 
  through Tuesday night. Temperatures will be much above normal 
  for this time of year.

* WIND...East winds gusting around 20 to 30 mph are possible
  tonight and Tuesday morning in east-wind prone locations. This
  includes higher elevations of the northwest Olympic Peninsula as
  well as the Cascades from the Glacier Peak area southward.

* IMPACTS...Outdoor burning is not recommended. Any new fires 
  could spread rapidly.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Red Flag Warning means that critical fire weather conditions
are either occurring now, or will shortly. A dry and unstable air
mass with warm temperatures can contribute to active fire
behavior. In western Washington, significant growth on existing
fires takes place under such conditions.

&&

$$

WAZ650-051600-
/O.CON.KSEW.FW.W.0004.000000T0000Z-170905T2000Z/
North Coastal Lowlands-
346 PM PDT Mon Sep 4 2017

...RED FLAG WARNING REMAINS IN EFFECT UNTIL 1 PM PDT TUESDAY FOR
WIND AND LOW HUMIDITY...

* WIND...Moderate East-Northeast breezes of 10 to 15 mph with
  gusts around 20 to 30 mph are expected to continue at times 
  until Tuesday morning. Strongest wind will be at higher exposed 
  locations such as Ellis Mountain. 

* TEMPERATURES/HUMIDITY...Hot temperatures are expected again on
  Tuesday, with highs reaching the upper 80s and lower 90s. This
  is much above normal for this time of year. Relative humidity
  values of 25 to 35 percent are expected. Nighttime humidity
  recovery will be very poor tonight above low-lying nighttime 
  inversions.

* IMPACTS...Outdoor burning is not recommended. Any new fires 
  could spread rapidly.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Red Flag Warning means that critical fire weather conditions
are either occurring now, or will shortly. A combination of a
moderate breeze, low relative humidity, and warm temperatures can
contribute to rapid rates of spread and downwind spotting on new
and existing fires.

&&

$$


www.weather.gov/seattle
133 
WWUS86 KSEW 052005
RFWSEW

URGENT - FIRE WEATHER MESSAGE
National Weather Service Seattle WA
105 PM PDT Tue Sep 5 2017

WAZ650-052115-
/O.EXP.KSEW.FW.W.0004.000000T0000Z-170905T2000Z/
North Coastal Lowlands-
105 PM PDT Tue Sep 5 2017

...RED FLAG WARNING HAS EXPIRED FOR WIND AND LOW HUMIDITY OVER THE
NORTHWEST OLYMPIC PENINSULA...

Winds have eased across the northwest Olympic Peninsula. 

$$

WAZ652-658-659-661-060300-
/O.CON.KSEW.FW.W.0004.000000T0000Z-170906T0300Z/
West Portion of the Olympic Mountains-
West Slopes of the North Cascades Generally above 1500 Feet-
West Slopes of the Central Cascades Generally above 1500 Feet-
East Portion of the Olympic Mountains-
105 PM PDT Tue Sep 5 2017

...RED FLAG WARNING REMAINS IN EFFECT UNTIL 8 PM PDT THIS EVENING
FOR A DRY AND UNSTABLE AIR MASS...

* HAINES...Mid-Level Haines 6 conditions are forecast through
  today. This indicates a dry and unstable air mass. 

* TEMPERATURES/HUMIDITY...Relative humidity below 25 percent with
  very poor nighttime humidity recovery again tonight. 
  Temperatures will be much above normal for this time of year.

* WIND...East winds gusting around 20 to 30 mph are possible
  through this evening in east-wind prone locations. This includes
  the Cascades from the Glacier Peak area southward. 

* IMPACTS...Outdoor burning is not recommended. Any new or
  existing fires could spread rapidly.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Red Flag Warning means that critical fire weather conditions
are either occurring now, or will shortly. A dry and unstable air
mass with warm temperatures can contribute to active fire
behavior. In western Washington, significant growth on existing
fires takes place under such conditions.

&&

$$


www.weather.gov/seattle

The office that day

Everything else NWS Seattle, WA issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Sep 3, 2:46 AM PDTSmall Craft AdvisorySEW20 hr
Sep 3, 2:31 PM PDTHeat AdvisorySEW55 hr

Nearby

Red Flag Warnings in Washington, 2017Every red flag warning in 2017

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.