Alert archive / Alabama / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 46, NWS Huntsville, AL

May 4, 2021DeKalb County, Jackson County, Alabama

NWS Huntsville, AL issued this severe thunderstorm warning at May 4, 2021, 9:39 AM CDT for DeKalb County, Jackson County, Alabama. It was in force for 36 min. 3 reports came from inside the area while it was in force.

The area

The outline as issued, with what was reported inside it.

The facts

Issued
May 4, 2021, 9:39 AM CDT (14:39 UTC)
Expired
May 4, 2021, 10:15 AM CDT
In force
36 min
Issued by
NWS Huntsville, AL
Area
Storm-based polygon
Hail
0.75 in
Wind
60.0 mph

Counties DeKalb County, AL, Jackson County, AL

The radar

The Northeast Alabama radar (KHTX), 38 km from the middle of the area, began a volume at 14:39 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.

What was reported inside it

TimeReportWhereRemark
May 4, 9:41 AM CDTTSTM WND DMG7 Se Bridgeport, ALA TREE WAS KNOCKED DOWN ON CR 318. TIME ESTIMATED BY RADAR.
May 4, 9:43 AM CDTTSTM WND DMG9 Se Bridgeport, ALA TREE WAS UPROOTED DAMAGING A FENCE AND SHED. SOCIAL MEDIA REPORT THROUGH BROADCAST MEDIA. TIME ESTIMATED BY RADAR.
May 4, 9:44 AM CDTTSTM WND DMG5 Nnw Ider, ALSOCIAL MEDIA REPORT OF A TREE KNOCKED DOWN IN FLAT ROCK.

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The watch it was issued in

The SPC watch in force over the same counties when this warning went out.

IssuedProductOfficeLasted
May 4, 5:13 AM CDTSevere Thunderstorm WatchSPC5 hr
May 4, 9:18 AM CDTTornado WatchSPC7 hr

The nearest sounding before it

Peachtre/Fal Fld, GA (KFFC), launched 12:00Z, 2.7 hours before the alert went out and 194 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, Peachtre/Fal Fld, GA at 12:00Z on 2021-05-04Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 590 joules per kilogram.LCLLFCEL10008507005003002001001 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, Peachtre/Fal Fld, GA at 12:00Z on 2021-05-04The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 207 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
590 J/kg
Mixed-layer CIN
-114 J/kg
Mixed-layer LCL
753 m above ground
0-6 km bulk shear
39 kt
0-1 km storm-relative helicity
207 m²/s²
0-3 km storm-relative helicity
213 m²/s²
Significant tornado parameter
0.0
Supercell composite
2.3

Open this sounding in Storm Lab

The text

As transmitted.

755 
WUUS54 KHUN 041439
SVRHUN
ALC049-071-041515-
/O.NEW.KHUN.SV.W.0046.210504T1439Z-210504T1515Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Huntsville AL
939 AM CDT Tue May 4 2021

The National Weather Service in Huntsville Alabama has issued a

* Severe Thunderstorm Warning for...
  Northeastern Jackson County in northeastern Alabama...
  Northeastern DeKalb County in northeastern Alabama...

* Until 1015 AM CDT.

* At 939 AM CDT, severe thunderstorms were located along a line
  extending from near Bridgeport to 7 miles southeast of Stevenson to
  near Henagar, moving northeast at 35 mph.

  HAZARD...60 mph wind gusts and penny size hail.

  SOURCE...Radar indicated.

  IMPACT...Expect damage to roofs, siding, and trees.

* Locations impacted include...
  Bridgeport, Henagar, Ider, Rosalie, Long Island, Russell Cave
  National Monument and Higdon.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Tornado Watch remains in effect until 400 PM CDT for northeastern
Alabama.

For your protection move to an interior room on the lowest floor of a
building.

&&

LAT...LON 3466 8578 3478 8576 3498 8583 3498 8560
      3486 8559 3471 8555
TIME...MOT...LOC 1439Z 241DEG 29KT 3496 8577 3482 8572 3461 8579 

HAIL...0.75IN
WIND...60MPH
 
$$

05/MA
1 follow-up statement
958 
WWUS54 KHUN 041456
SVSHUN

Severe Weather Statement
National Weather Service Huntsville AL
956 AM CDT Tue May 4 2021

ALC049-071-041515-
/O.CON.KHUN.SV.W.0046.000000T0000Z-210504T1515Z/
Jackson AL-DeKalb AL-
956 AM CDT Tue May 4 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 1015 AM CDT
FOR NORTHEASTERN JACKSON AND NORTHEASTERN DEKALB COUNTIES...

At 955 AM CDT, severe thunderstorms were located along a line
extending from near South Pittsburg to 6 miles west of Trenton to
near Henagar, moving northeast at 30 mph.

HAZARD...60 mph wind gusts.

SOURCE...Radar indicated.

IMPACT...Expect damage to roofs, siding, and trees.

Locations impacted include...
Bridgeport, Henagar, Ider, Higdon and Long Island. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Tornado Watch remains in effect until 400 PM CDT for northeastern
Alabama.

For your protection move to an interior room on the lowest floor of a
building.

&&

LAT...LON 3466 8578 3482 8570 3498 8570 3498 8560
      3486 8559 3471 8555
TIME...MOT...LOC 1455Z 245DEG 24KT 3499 8567 3485 8562 3464 8569 

HAIL...<.75IN
WIND...60MPH
 
$$

05/MA

The office that day

Everything else NWS Huntsville, AL issued on the same UTC day.

IssuedProductOfficeCountiesLasted
May 4, 7:18 AM CDTSpecial Weather StatementHUNColbert42 min
May 4, 7:45 AM CDTSpecial Weather StatementHUNCullman60 min
May 4, 8:31 AM CDTSpecial Weather StatementHUNLimestone, Madison, Morgan44 min
May 4, 9:01 AM CDTSpecial Weather StatementHUNJackson44 min
May 4, 9:04 AM CDTSevere Thunderstorm WarningHUNJackson26 min
May 4, 9:23 AM CDTSpecial Weather StatementHUNDeKalb52 min
May 4, 9:25 AM CDTSpecial Weather StatementHUNCullman, Morgan50 min
May 4, 9:31 AM CDTSevere Thunderstorm WarningHUNCullman, Morgan39 min
May 4, 9:51 AM CDTSevere Thunderstorm WarningHUNDeKalb24 min
May 4, 10:17 AM CDTSpecial Weather StatementHUNDeKalb58 min
May 4, 10:47 AM CDTFlash Flood WarningHUNDeKalb, Marshall3 hr
May 4, 10:51 AM CDTSpecial Weather StatementHUNMarshall39 min
May 4, 11:15 AM CDTSpecial Weather StatementHUNCullman45 min
May 4, 11:18 AM CDTSevere Thunderstorm WarningHUNCullman42 min
May 4, 3:37 PM CDTSpecial Weather StatementHUNFranklin23 min
May 4, 4:18 PM CDTSpecial Weather StatementHUNLauderdale27 min
May 4, 5:10 PM CDTSpecial Weather StatementHUNCullman35 min
May 4, 5:56 PM CDTSpecial Weather StatementHUNMadison49 min
May 4, 6:01 PM CDTSpecial Weather StatementHUNMarshall44 min
May 4, 6:16 PM CDTSpecial Weather StatementHUNMadison44 min

Nearby

Severe Thunderstorm Warnings in Alabama, 2021Every severe thunderstorm 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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.