Alert archive / Alabama / Red Flag Warnings in 2011

Red Flag Warning 6, NWS Birmingham, AL

March 17, 201111 counties in Alabama

NWS Birmingham, AL issued this red flag warning at Mar 17, 2011, 2:18 PM CDT for 11 counties in Alabama. It was in force for 5 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: Mar 17, 2011, 2:18 PM CDT (19:18 UTC)
Expired: Mar 17, 2011, 7:00 PM CDT
In force: 5 hr
Issued by: NWS Birmingham, AL

Counties Blount County, AL, Calhoun County, AL, Cherokee County, AL, Clay County, AL, Cleburne County, AL, Etowah County, AL, Jefferson County, AL, Randolph County, AL, Shelby County, AL, St. Clair County, AL, Talladega County, AL

The radar

The Birmingham radar (KBMX), 83 km from the middle of the area, began a volume at 19:19 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

Birmingham, AL (KBMX), launched 12:00Z, 7.3 hours before the alert went out and 83 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 2195 m above ground
0-6 km bulk shear: 16 kt
0-1 km storm-relative helicity: 76 m²/s²
0-3 km storm-relative helicity: 89 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

436 
WWUS84 KBMX 171918
RFWBMX

URGENT - FIRE WEATHER MESSAGE
NATIONAL WEATHER SERVICE BIRMINGHAM AL
218 PM CDT THU MAR 17 2011

...DRY CONDITIONS ARE EXPECTED THIS AFTERNOON...

.CRITICAL FIRE WEATHER PARAMETERS WILL BE MET FOR 4 HOURS THIS
AFTERNOON.

ALZ017>021-024>029-180000-
/O.NEW.KBMX.FW.W.0006.110317T1918Z-110318T0000Z/
BLOUNT-ETOWAH-CALHOUN-CHEROKEE-CLEBURNE-JEFFERSON-SHELBY-
ST. CLAIR-TALLADEGA-CLAY-RANDOLPH-
218 PM CDT THU MAR 17 2011

...RED FLAG WARNING IN EFFECT UNTIL 7 PM CDT THIS EVENING...

THE NATIONAL WEATHER SERVICE IN BIRMINGHAM HAS ISSUED A RED FLAG
WARNING...WHICH IS IN EFFECT UNTIL 7 PM CDT THIS EVENING. 

RELATIVE HUMIDITIES HAVE DROPPED BELOW 25 PERCENT IN SEVERAL SPOTS
OVER THE PAST HOUR. LOOK FOR THESE RH VALUES TO REMAIN BELOW 25 FOR
AT LEAST 4 HOURS THIS AFTERNOON. SURFACE DEWPOINTS HAVE FALLEN
INTO THE LOW 30S AND WILL REMAIN THERE FOR THE REST OF THE
AFTERNOON. OTHER AREAS ADJACENT TO THE WARNING MAY SEE RH VALUES
BELOW 25 PERCENT...BUT THE DURATION WILL BE LESS THAN 4 HOURS.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A RED FLAG WARNING MEANS THAT CRITICAL FIRE WEATHER CONDITIONS
ARE EITHER OCCURRING NOW...OR WILL SHORTLY. A COMBINATION OF
WINDS...LOW RELATIVE HUMIDITY...AND WARM TEMPERATURES WILL CREATE
EXPLOSIVE FIRE GROWTH POTENTIAL.

FOR ADDITIONAL INFORMATION ON THE FIRE CONDITIONS...PLEASE
CONTACT THE ALABAMA FORESTRY COMMISSION AT
WWW.FORESTRY.ALABAMA.GOV.

&&

$$

Nearby

Red Flag Warnings in Alabama, 2011 Every red flag warning in 2011

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.