Alert archive / Alabama / Severe Thunderstorm Warnings in 2018

Severe Thunderstorm Warning 111, NWS Huntsville, AL

August 17, 2018DeKalb County, Jackson County, Alabama

NWS Huntsville, AL issued this severe thunderstorm warning at Aug 17, 2018, 7:28 PM CDT for DeKalb County, Jackson County, Alabama. It was in force for 32 min. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued: Aug 17, 2018, 7:28 PM CDT (00:28 UTC)
Expired: Aug 17, 2018, 8:00 PM CDT
In force: 32 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 00:28 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

Nashville Metro, TN (KBNA), launched 00:00Z, 0.5 hours before the alert went out and 180 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: 152 J/kg
Mixed-layer CIN: -36 J/kg
Mixed-layer LCL: 1268 m above ground
0-6 km bulk shear: 30 kt
0-1 km storm-relative helicity: 66 m²/s²
0-3 km storm-relative helicity: 100 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.5

Open this sounding in Storm Lab

What forecasters said that day

The local office's own words before this severe thunderstorm warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Huntsville, AL wrote its last area forecast discussion before this severe thunderstorm warning went out at Aug 17, 6:54 PM CDT, 34 minutes earlier.

Area forecast discussion, Aug 17, 6:54 PM CDT, 34 minutes before

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Hazardous weather outlook, Aug 17, 2:53 PM CDT, 4 hours 35 minutes before

Hazardous Weather Outlook
National Weather Service Huntsville AL
253 PM CDT Fri Aug 17 2018

ALZ001>010-016-TNZ076-096-097-181100-
Lauderdale-Colbert-Franklin AL-Lawrence-Limestone-Madison-Morgan-
Marshall-Jackson-DeKalb-Cullman-Moore-Lincoln-Franklin TN-
253 PM CDT Fri Aug 17 2018

This Hazardous Weather Outlook is for north Alabama and portions of
southern middle Tennessee.

.DAY ONE...This afternoon and Tonight...

Scattered to numerous thunderstorms are forecast to impact the
Tennessee Valley, this afternoon and evening. Some of the storms
could become strong to marginally severe, with strong wind gusts the
primary threat. Heavy downpours and frequent lightning will also
accompany the stronger storms.

.DAYS TWO THROUGH SEVEN...Saturday through Thursday...

Additional scattered to numerous thunderstorms are forecast across
the region this weekend, continuing into the middle of next week.
Gusty winds, very heavy rainfall and frequent lightning are all
possible in the stronger storms. A cold front is forecast to move
across the region late Tuesday into Wednesday. Thunderstorm activity
should end from west to east during Wednesday.

.SPOTTER CALL TO ACTION STATEMENT...

Activation of storm spotters and emergency management personnel is
not anticipated at this time.

In the hours before

Special weather statement, Aug 17, 5:27 PM CDT, 2 hours 1 minute before

Special Weather Statement
National Weather Service Huntsville AL
527 PM CDT FRI AUG 17 2018

ALZ006>009-016-172315-
Marshall AL-Madison AL-Morgan AL-Cullman AL-Jackson AL-
527 PM CDT FRI AUG 17 2018

...SIGNIFICANT WEATHER ADVISORY FOR WEST CENTRAL JACKSON...
NORTHWESTERN MARSHALL...SOUTHEASTERN MADISON...NORTH CENTRAL CULLMAN
AND SOUTHEASTERN MORGAN COUNTIES UNTIL 615 PM CDT...

At 526 PM CDT, Doppler radar was tracking strong thunderstorms along
a line extending from Owens Cross Roads to near Morgan City to near
Falkville. Movement was east at 15 mph.

Winds in excess of 40 mph will be possible with these storms.

Locations impacted include...
Southern Huntsville, Arab, Redstone Arsenal, Owens Cross Roads,
Grant, Skyline, Gurley, Woodville, Morgan City and Vinemont.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Strong gusty winds will be capable of knocking down small tree limbs
along with other small unsecured items. Seek safe shelter until this
line of storms has passed.

&&

LAT...LON 3479 8607 3447 8628 3419 8668 3425 8704
      3447 8672 3472 8654
TIME...MOT...LOC 2226Z 268DEG 12KT 3466 8650 3447 8663 3428 8690

AMP

Special weather statement, Aug 17, 5:31 PM CDT, 1 hour 57 minutes before

Special Weather Statement
National Weather Service Huntsville AL
531 PM CDT FRI AUG 17 2018

ALZ006-009-TNZ076-096-097-172315-
Madison AL-Jackson AL-Franklin TN-Moore TN-Lincoln TN-
531 PM CDT FRI AUG 17 2018

...SIGNIFICANT WEATHER ADVISORY FOR NORTHWESTERN JACKSON...
NORTHEASTERN MADISON...SOUTH CENTRAL MOORE...SOUTHEASTERN LINCOLN AND
WESTERN FRANKLIN COUNTIES UNTIL 615 PM CDT...

At 528 PM CDT, Doppler radar was tracking strong thunderstorms along
a line extending from Huntland to near New Market to Gurley.
Movement was northeast at 20 mph.

Wind gusts up to 50 mph will be possible with these storms.

Locations impacted include...
Winchester, Decherd, Estill Springs, Huntland, Skyline, Tims Ford
Lake, New Market, Hytop, Jericho, Gurley, and Elora.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Strong gusty winds will be capable of knocking down small tree limbs
along with other small unsecured items. Seek safe shelter until this
line of storms has passed.

&&

LAT...LON 3529 8608 3501 8606 3478 8610 3470 8652
      3487 8647 3511 8648
TIME...MOT...LOC 2228Z 241DEG 19KT 3508 8642 3493 8638 3480 8642

AMP

Special weather statement, Aug 17, 5:39 PM CDT, 1 hour 49 minutes before

Special Weather Statement
National Weather Service Huntsville AL
539 PM CDT FRI AUG 17 2018

ALZ016-172315-
Cullman AL-
539 PM CDT FRI AUG 17 2018

...SIGNIFICANT WEATHER ADVISORY FOR SOUTHWESTERN CULLMAN COUNTY UNTIL
615 PM CDT...

At 539 PM CDT, Doppler radar was tracking a strong thunderstorm over
Arkadelphia, or 11 miles northeast of Sumiton, moving northeast at
25 mph.

Winds in excess of 40 mph will be possible with this storm.

Locations impacted include...
Hanceville, Good Hope, Dodge City, Garden City, Colony, Walter,
Wilburn, Bremen, Arkadelphia and Black Bottom.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Strong gusty winds will be capable of knocking down small tree limbs
along with other small unsecured items. Seek safe shelter until this
storm has passed.

&&

LAT...LON 3389 8701 3389 8705 3394 8708 3418 8670
      3411 8665 3409 8666 3408 8670 3405 8668
      3406 8671 3403 8670 3395 8679 3396 8682
      3393 8686 3394 8688 3391 8692 3387 8694
      3386 8699
TIME...MOT...LOC 2239Z 239DEG 27KT 3390 8695

AMP

Special weather statement, Aug 17, 5:53 PM CDT, 1 hour 35 minutes before

Special Weather Statement
National Weather Service Huntsville AL
553 PM CDT FRI AUG 17 2018

ALZ008-010-172330-
Marshall AL-DeKalb AL-
553 PM CDT FRI AUG 17 2018

...SIGNIFICANT WEATHER ADVISORY FOR SOUTHEASTERN MARSHALL AND
SOUTHWESTERN DEKALB COUNTIES UNTIL 630 PM CDT...

At 553 PM CDT, Doppler radar was tracking a strong thunderstorm near
McLarty, or 8 miles west of Albertville, moving northeast at 15 mph.

Winds in excess of 40 mph will be possible with this storm.

Locations impacted include...
Albertville, Boaz, Guntersville, Douglas, McVille, High Point,
Horton, Lake Guntersville St Park, Arona and Painter.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Strong gusty winds will be capable of knocking down small tree limbs
along with other small unsecured items. Seek safe shelter until this
storm has passed.

&&

LAT...LON 3414 8634 3421 8642 3426 8645 3447 8615
      3423 8600 3418 8616 3418 8619 3417 8621
      3413 8634
TIME...MOT...LOC 2253Z 241DEG 13KT 3423 8636

AMP

Special weather statement, Aug 17, 6:21 PM CDT, 1 hour 7 minutes before

Special Weather Statement
National Weather Service Huntsville AL
621 PM CDT FRI AUG 17 2018

ALZ008>010-180000-
Marshall AL-DeKalb AL-Jackson AL-
621 PM CDT FRI AUG 17 2018

...SIGNIFICANT WEATHER ADVISORY FOR SOUTH CENTRAL JACKSON...MARSHALL
AND SOUTHWESTERN DEKALB COUNTIES UNTIL 700 PM CDT...

At 620 PM CDT, Doppler radar was tracking strong thunderstorms along
a line extending from 7 miles southeast of Grant to near Albertville
to near Walnut Grove. Movement was east at 30 mph.

Wind gusts up to 50 mph will be possible with these storms.

Locations impacted include...
Albertville, Boaz, Guntersville, Rainsville, Crossville, Sylvania,
Fyffe, Powell, Grant and Geraldine.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Strong gusty winds will be capable of knocking down small tree limbs
along with other small unsecured items. Seek safe shelter until this
line of storms has passed.

Frequent cloud to ground lightning is occurring with these storms.
Lightning can strike several miles away from a thunderstorm. Seek a
safe shelter inside a building or vehicle.

&&

LAT...LON 3421 8642 3428 8638 3452 8635 3451 8634
      3453 8632 3460 8584 3434 8587 3420 8596
      3420 8611 3419 8611 3418 8619 3410 8630
TIME...MOT...LOC 2320Z 252DEG 28KT 3446 8615 3427 8616 3413 8628

AMP

Special weather statement, Aug 17, 6:59 PM CDT, 29 minutes before

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The office that day

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

Issued	Product	Office	Counties	Lasted
Aug 17, 7:34 PM CDT	Special Weather Statement	HUN	Franklin	41 min
Aug 17, 8:13 PM CDT	Special Weather Statement	HUN	Lawrence	32 min
Aug 17, 8:47 PM CDT	Special Weather Statement	HUN	Lauderdale, Limestone	43 min

Nearby

Severe Thunderstorm Warnings in Alabama, 2018 Every severe thunderstorm warning in 2018

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.