Alert archive / Nebraska / Red Flag Warnings in 2017

Red Flag Warning 12, NWS North Platte, NE

September 20, 20174 counties in Nebraska

NWS North Platte, NE issued this red flag warning at Sep 20, 2017, 2:41 PM MDT for 4 counties in Nebraska. It took effect at Sep 21, 2017, 12:00 PM MDT. 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
Sep 20, 2017, 2:41 PM MDT (20:41 UTC)
In effect from
Sep 21, 2017, 12:00 PM MDT
Expired
Sep 21, 2017, 6:59 PM MDT
In force
7 hr
Issued by
NWS North Platte, NE

Counties Chase County, NE, Hayes County, NE, Lincoln County, NE, Perkins County, NE

The radar

The North Platte radar (KLNX), 148 km from the middle of the area, began a volume at 20:45 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

N. Platte/Lee Bi, NE (KLBF), launched 12:00Z, 8.7 hours before the alert went out and 73 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, N. Platte/Lee Bi, NE at 12:00Z on 2017-09-20Temperature 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, N. Platte/Lee Bi, NE at 12:00Z on 2017-09-20The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -126 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
2156 m above ground
0-6 km bulk shear
65 kt
0-1 km storm-relative helicity
-126 m²/s²
0-3 km storm-relative helicity
1 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

750 
WWUS83 KLBF 202041
RFWLBF

URGENT - FIRE WEATHER MESSAGE
National Weather Service North Platte NE
341 PM CDT Wed Sep 20 2017

...RED FLAG WARNING IN EFFECT FOR THURSDAY AFTERNOON THROUGH 
EARLY THURSDAY EVENING FOR GUSTY WINDS AND LOW RELATIVE HUMIDITY 
OVER PORTIONS OF SOUTHWEST NEBRASKA...

.Gusty south to southwest winds will develop Thursday afternoon 
which will support critical fire weather conditions across 
portions of southwest Nebraska. In addition, relative humidity
values will drop to less than 15 percent by late afternoon. 

The combination of low relative humidity and gusty winds are
expected to produce critical fire weather conditions.

NEZ210-211045-
/O.UPG.KLBF.FW.A.0006.170921T1800Z-170922T0100Z/
/O.NEW.KLBF.FW.W.0012.170921T1800Z-170922T0100Z/
Frenchman Basin-
241 PM MDT Wed Sep 20 2017

...RED FLAG WARNING IN EFFECT FROM NOON TO 7 PM MDT THURSDAY FOR
LOW RELATIVE HUMIDITY VALUES AND GUSTY WINDS FOR FIRE WEATHER 
ZONE 210...

The National Weather Service in North Platte has issued a Red
Flag Warning, which is in effect from noon to 7 PM MDT Thursday.
The Fire Weather Watch is no longer in effect. 

* AFFECTED AREA...Fire weather zone 210.

* WIND...South at 15 to 25 mph with higher gusts.

* HUMIDITY...Minimum relative humidity 10 to 15 percent.

* IMPACTS...This combination of gusty winds and low relative
  humidities would produce critical fire weather conditions.

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.

&&

$$

JWS
3 follow-up statements
307 
WWUS83 KLBF 210915
RFWLBF

URGENT - FIRE WEATHER MESSAGE
National Weather Service North Platte NE
415 AM CDT Thu Sep 21 2017

...RED FLAG WARNING REMAINS IN EFFECT FOR THIS AFTERNOON THROUGH 
EARLY EVENING FOR GUSTY WINDS AND LOW RELATIVE HUMIDITY OVER 
PORTIONS OF SOUTHWEST NEBRASKA...

.Gusty south winds will develop this afternoon which will support
critical fire weather conditions across portions of southwest 
Nebraska. In addition, relative humidity values will drop to less 
than 15 percent.

The combination of low relative humidity and gusty winds are
expected to produce critical fire weather conditions.

NEZ210-220100-
/O.CON.KLBF.FW.W.0012.170921T1800Z-170922T0100Z/
Frenchman Basin-
315 AM MDT Thu Sep 21 2017

...RED FLAG WARNING REMAINS IN EFFECT FROM NOON TODAY TO 7 PM MDT
THIS EVENING FOR LOW RELATIVE HUMIDITY VALUES AND GUSTY WINDS FOR
FIRE WEATHER ZONE 210...

* AFFECTED AREA...Fire weather zone 210.

* WIND...South at 15 to 25 mph with higher gusts.

* HUMIDITY...Minimum relative humidity 10 to 15 percent.

* IMPACTS...This combination of gusty winds and low relative 
  humidities would produce critical fire weather conditions.

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.

&&

$$

CLB
328 
WWUS83 KLBF 212058 AAA
RFWLBF

URGENT - FIRE WEATHER MESSAGE...UPDATED
National Weather Service North Platte NE
358 PM CDT Thu Sep 21 2017

...RED FLAG WARNING REMAINS IN EFFECT FOR LATE THIS AFTERNOON 
THROUGH EARLY EVENING FOR GUSTY WINDS AND LOW RELATIVE HUMIDITY 
OVER PORTIONS OF SOUTHWEST NEBRASKA...

.Gusty south winds will develop this afternoon which will support
critical fire weather conditions across portions of southwest
Nebraska. In addition, relative humidity values will drop to less
than 15 percent.

The combination of low relative humidity and gusty winds are
expected to produce critical fire weather conditions.

NEZ210-220100-
/O.CON.KLBF.FW.W.0012.000000T0000Z-170922T0100Z/
Frenchman Basin-
258 PM MDT Thu Sep 21 2017

...RED FLAG WARNING REMAINS IN EFFECT UNTIL 7 PM MDT THIS EVENING
FOR LOW RELATIVE HUMIDITY VALUES AND GUSTY WINDS FOR FIRE WEATHER
ZONE 210...

* AFFECTED AREA...Fire weather zone 210.

* WIND...South at 15 to 25 mph with higher gusts.

* HUMIDITY...Minimum relative humidity 10 to 15 percent.

* IMPACTS...This combination of gusty winds and low relative 
  humidities would produce critical fire weather conditions.

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.

&&

$$

POWER
910 
WWUS83 KLBF 220059
RFWLBF

URGENT - FIRE WEATHER MESSAGE
National Weather Service North Platte NE
759 PM CDT Thu Sep 21 2017

...RED FLAG EXPIRED OVER FAR SOUTHWEST NEBRASKA...

NEZ210-220200-
/O.CAN.KLBF.FW.W.0012.000000T0000Z-170922T0100Z/
Frenchman Basin-
659 PM MDT Thu Sep 21 2017

...RED FLAG WARNING IS CANCELLED FOR LOW RELATIVE HUMIDITY VALUES
AND GUSTY WINDS FOR FIRE WEATHER ZONE 210...

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

Relative humidity has increased with cooling temperatures and,
combined with winds lessening some, critical fire weather
conditions are no longer expected.

$$

ET

The office that day

Everything else NWS North Platte, NE issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Sep 19, 7:41 PM MDTSevere Thunderstorm WarningLBFKeya Paha19 min
Sep 19, 7:59 PM MDTSevere Thunderstorm WarningLBFBoyd, Keya Paha22 min
Sep 20, 2:32 AM MDTFire Weather WatchLBFChase, Hayes, Lincoln, Perkins12 hr

Nearby

Red Flag Warnings in Nebraska, 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.