Alert archive / Colorado / Red Flag Warnings in 2019

Red Flag Warning 13, NWS Denver/Boulder, CO

October 4, 20198 counties in Colorado

NWS Denver/Boulder, CO issued this red flag warning at Oct 4, 2019, 7:12 PM MDT for 8 counties in Colorado. It took effect at Oct 5, 2019, 11:00 AM MDT. It was in force for 9 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
Oct 4, 2019, 7:12 PM MDT (01:12 UTC)
In effect from
Oct 5, 2019, 11:00 AM MDT
Expired
Oct 5, 2019, 8:00 PM MDT
In force
9 hr
Issued by
NWS Denver/Boulder, CO

Counties Boulder County, CO, Clear Creek County, CO, Gilpin County, CO, Grand County, CO, Jackson County, CO, Larimer County, CO, Park County, CO, Summit County, CO

The radar

The Denver radar (KFTG), 108 km from the middle of the area, began a volume at 01:12 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

Denver, CO (KDNR), launched 00:00Z, 1.2 hours before the alert went out and 218 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, Denver, CO at 00:00Z on 2019-10-05Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 209 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Denver, CO at 00:00Z on 2019-10-05The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 280 square meters per square second.1939587897Sfc1 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
209 J/kg
Mixed-layer CIN
-296 J/kg
Mixed-layer LCL
2544 m above ground
0-6 km bulk shear
63 kt
0-1 km storm-relative helicity
280 m²/s²
0-3 km storm-relative helicity
328 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

234 
WWUS85 KBOU 050112
RFWBOU

URGENT - FIRE WEATHER MESSAGE
National Weather Service Denver/Boulder CO
712 PM MDT Fri Oct 4 2019

...CRITICAL FIRE WEATHER CONDITIONS EXPECTED SATURDAY AFTERNOON 
AND EVENING ACROSS THE HIGH MOUNTAINS AND NORTH PARK...

Although the Red Flag Warning for today had been allowed to
expire, fire weather conditions will remain elevated in the 
mountains and foothills overnight. A dry cold front will bring 
strong northwest winds this evening. Relative humidities will 
recover overnight, but very slowly, which will allow for the fire
danger to remain elevated due to the windy conditions.

Drier humidity is expected Saturday with weaker northwest winds,
but could again reach criteria. Critical fire weather conditions 
are expected to affect North Park and the higher mountains. 
Therefore a Red Flag Warning will be in effect for those areas 
from 11 am to 8 pm mdt Saturday. 

COZ211-212-218-051100-
/O.EXP.KBOU.FW.W.0012.000000T0000Z-191005T0100Z/
/O.UPG.KBOU.FW.A.0007.191005T1800Z-191006T0000Z/
/O.NEW.KBOU.FW.W.0013.191005T1700Z-191006T0200Z/
Jackson County Below 9000 Feet-
South and Southeast Grand/West Central and Southwest Boulder/
Gilpin/Clear Creek/Summit/North and West Park Counties Above
9000 Feet-
South and East Jackson/Larimer/North and Northeast Grand/
Northwest Boulder Counties Above 9000 Feet-
712 PM MDT Fri Oct 4 2019

...RED FLAG WARNING IN EFFECT FROM 11 AM TO 8 PM MDT SATURDAY FOR
WIND AND LOW RELATIVE HUMIDITY FOR THE HIGH MOUNTAINS AND NORTH
PARK... 

The National Weather Service in Denver has issued a Red Flag 
Warning FOR WIND AND LOW RELATIVE HUMIDITY, which is in effect 
from 11 AM to 8 PM MDT Saturday. The Fire Weather Watch is no 
longer in effect.

* Affected Area...Fire Weather Zones 211...212 and 218.

* Winds...West 15 to 25 mph with gusts up to 45 mph.

* Timing...11 am to 8 pm MDT Saturday.

* Relative Humidity...As low as 10 percent.

* Impacts...Conditions will be favorable for the rapid ignition, 
  growth, and spread of fires. A wind shift early this evening 
  from southwest to northwest would change the spread of fires 
  if started.

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.

&&

$$

COZ213>217-050215-
/O.EXP.KBOU.FW.W.0012.000000T0000Z-191005T0100Z/
Grand and Summit Counties Below 9000 Feet-
Central and Southeast Park County-
Larimer and Boulder Counties Between 6000 and 9000 Feet-
Jefferson and West Douglas Counties Above 6000 Feet/Gilpin/Clear
Creek/Northeast Park Counties Below 9000 Feet-
West Jackson and West Grand Counties Above 9000 Feet-
712 PM MDT Fri Oct 4 2019

...RED FLAG WARNING EXPIRED AT 7 PM MDT THIS EVENING FOR WIND AND
LOW RELATIVE HUMIDITY FOR THE PARK RANGE MOUNTAINS, MIDDLE PARKS 
AND THE FRONT RANGE FOOTHILLS...

Although the Red Flag Warning has been allowed to expire, the fire 
danger will remain elevated due to gusty northwest winds
overnight. Relative humidities will recover overnight, but very
slowly.

$$
3 follow-up statements
106 
WWUS85 KBOU 050955
RFWBOU

URGENT - FIRE WEATHER MESSAGE
National Weather Service Denver/Boulder CO
355 AM MDT Sat Oct 5 2019

...CRITICAL FIRE WEATHER CONDITIONS LATE THIS MORNING THROUGH
EARLY THIS EVENING ACROSS THE MOUNTAINS AND NORTH PARK...

Lower humidity combined with gusty west winds up to 40 mph
will lead to critical fire danger over the Mountains and North 
Park.

COZ211-212-218-051800-
/O.CON.KBOU.FW.W.0013.191005T1700Z-191006T0200Z/
Jackson County Below 9000 Feet-
South and Southeast Grand/West Central and Southwest Boulder/
Gilpin/Clear Creek/Summit/North and West Park Counties Above
9000 Feet-
South and East Jackson/Larimer/North and Northeast Grand/
Northwest Boulder Counties Above 9000 Feet-
355 AM MDT Sat Oct 5 2019

...RED FLAG WARNING REMAINS IN EFFECT FROM 11 AM THIS MORNING TO
8 PM MDT THIS EVENING FOR WIND AND LOW RELATIVE HUMIDITY FOR THE
MOUNTAINS AND NORTH PARK...

* Affected Area...Fire Weather Zones 211...212 and 218.

* Winds...West 15 to 25 mph with gusts up to 40 mph.

* Timing...11 am to 8 pm MDT Saturday.

* Relative Humidity...As low as 10 percent.

* Impacts...Conditions will be favorable for the rapid ignition,
  growth, and spread of fires. 

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.

&&

$$
331 
WWUS85 KBOU 051814
RFWBOU

URGENT - FIRE WEATHER MESSAGE
National Weather Service Denver/Boulder CO
1214 PM MDT Sat Oct 5 2019

...CRITICAL FIRE WEATHER CONDITIONS THROUGH EARLY THIS EVENING 
ACROSS THE MOUNTAINS AND NORTH PARK...

Gusty west winds will become widespread across the central and
northern Colorado mountains and North Park this afternoon. This
will create dangerous fire weather conditions.

COZ211-212-218-060200-
/O.CON.KBOU.FW.W.0013.000000T0000Z-191006T0200Z/
Jackson County Below 9000 Feet-
South and Southeast Grand/West Central and Southwest Boulder/
Gilpin/Clear Creek/Summit/North and West Park Counties Above
9000 Feet-
South and East Jackson/Larimer/North and Northeast Grand/
Northwest Boulder Counties Above 9000 Feet-
1214 PM MDT Sat Oct 5 2019

...RED FLAG WARNING REMAINS IN EFFECT UNTIL 8 PM MDT THIS EVENING
FOR WIND AND LOW RELATIVE HUMIDITY FOR THE MOUNTAINS AND NORTH
PARK...

* Affected Area...Fire Weather Zones 211...212 and 218.

* Winds...West 10 to 20 mph with gusts up to 35 mph.

* Timing...Until 8 pm MDT Saturday.

* Relative Humidity...As low as 10 percent.

* Impacts...Conditions will be favorable for the rapid ignition, 
  growth, and spread of fires.

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.

&&

$$

Gimmestad
440 
WWUS85 KBOU 060210
RFWBOU

URGENT - FIRE WEATHER MESSAGE
National Weather Service Denver/Boulder CO
810 PM MDT Sat Oct 5 2019

COZ211-212-218-060315-
/O.EXP.KBOU.FW.W.0013.000000T0000Z-191006T0200Z/
Jackson County Below 9000 Feet-
South and Southeast Grand/West Central and Southwest Boulder/
Gilpin/Clear Creek/Summit/North and West Park Counties Above
9000 Feet-
South and East Jackson/Larimer/North and Northeast Grand/
Northwest Boulder Counties Above 9000 Feet-
810 PM MDT Sat Oct 5 2019

...RED FLAG WARNING HAS EXPIRED FOR WIND AND LOW RELATIVE
HUMIDITY FOR the northern and central mountains above 9000 feet.

Winds have decreased across the high country this evening,
dropping well below red flag values. Across the highest 
elevations winds could still gust over 20 mph through midnight 
tonight. In addition to the reduction in wind speeds, cooling 
temperatures have lead to relative humidity recovery such that 
values are in the 20 percent or high range presently, with further
improvement expected overnight. Thus, the red flag warning has 
been allowed to expire.

$$

The office that day

Everything else NWS Denver/Boulder, CO issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Oct 5, 3:21 PM MDTFrost AdvisoryBOUElbert, Lincoln16 hr

Nearby

Red Flag Warnings in Colorado, 2019Every red flag warning in 2019

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.