Alert archive / Alabama / Areal Flood Warnings in 2021

Areal Flood Warning 8, NWS Huntsville, AL

March 18, 2021Marshall County, Alabama

NWS Huntsville, AL issued this areal flood warning at Mar 18, 2021, 12:03 AM CDT for Marshall County, Alabama. It was in force for 117 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: Mar 18, 2021, 12:03 AM CDT (05:03 UTC)
Expired: Mar 18, 2021, 2:00 AM CDT
In force: 117 min
Issued by: NWS Huntsville, AL
Area: Storm-based polygon
Flood severity: None

County Marshall County, AL

The radar

The Northeast Alabama radar (KHTX), 66 km from the middle of the area, began a volume at 05:07 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 00:00Z, 5.1 hours before the alert went out and 139 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: 188 J/kg
Mixed-layer CIN: -25 J/kg
Mixed-layer LCL: 669 m above ground
0-6 km bulk shear: 63 kt
0-1 km storm-relative helicity: 336 m²/s²
0-3 km storm-relative helicity: 465 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.6

Open this sounding in Storm Lab

What forecasters said that day

The local office's own words before this areal flood 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 areal flood warning went out at Mar 18, 12:00 AM CDT, 3 minutes earlier.

Area forecast discussion, Mar 18, 12:00 AM CDT, 3 minutes before

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Hazardous weather outlook, Mar 17, 10:53 PM CDT, 1 hour 10 minutes before

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In the hours before

Special weather statement, Mar 17, 8:50 PM CDT, 3 hours 13 minutes before

Special Weather Statement
National Weather Service Huntsville AL
850 PM CDT Wed Mar 17 2021

ALZ001>004-180215-
Lawrence AL-Lauderdale AL-Franklin AL-Colbert AL-
850 PM CDT Wed Mar 17 2021

...SIGNIFICANT WEATHER ADVISORY FOR LAUDERDALE...COLBERT...EASTERN
FRANKLIN AND LAWRENCE COUNTIES UNTIL 915 PM CDT...

At 849 PM CDT, Doppler radar was tracking strong thunderstorms along
a line extending from 6 miles east of Iuka to near Tuscumbia to 6
miles north of Needmore. Movement was to the north-northeast at 65
mph.

Penny size hail and wind gusts up to 50 mph will be possible with
these storms.

Locations impacted include...
Florence, Muscle Shoals, Russellville, Sheffield, Tuscumbia, Moulton,
Phil Campbell, Killen, Town Creek and Cherokee.

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.

Very heavy rainfall is also occurring with these storms, and may lead
to localized flooding. Do not drive your vehicle through flooded
roadways.

&&

LAT...LON 3501 8817 3500 8747 3471 8729 3431 8716
      3430 8719 3431 8769 3452 8782 3468 8813
      3489 8810 3494 8817 3497 8818
TIME...MOT...LOC 0149Z 198DEG 56KT 3484 8809 3466 8775 3434 8755

70/DD

Special weather statement, Mar 17, 9:14 PM CDT, 2 hours 49 minutes before

Special Weather Statement
National Weather Service Huntsville AL
914 PM CDT Wed Mar 17 2021

ALZ016-180245-
Cullman AL-
914 PM CDT Wed Mar 17 2021

...SIGNIFICANT WEATHER ADVISORY FOR CULLMAN COUNTY UNTIL 945 PM
CDT...

At 914 PM CDT, Doppler radar was tracking strong thunderstorms along
a line extending from near Falkville to near Dodge City to Sumiton.
Movement was northeast at 45 mph.

Penny size hail and wind gusts up to 50 mph will be possible with
these storms.

Locations impacted include...
Cullman, Hanceville, Good Hope, Holly Pond, Dodge City, Baldwin,
Vinemont, Baileyton, West Point and Garden City.

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.

Very heavy rainfall is also occurring with these storms, and may lead
to localized flooding. Do not drive your vehicle through flooded
roadways.

&&

LAT...LON 3389 8701 3389 8709 3400 8705 3430 8703
      3430 8659 3422 8654 3412 8660 3412 8663
      3408 8670 3405 8668 3406 8671 3403 8670
      3398 8676 3393 8686 3394 8688 3392 8689
      3391 8692 3387 8692 3386 8696 3386 8699
TIME...MOT...LOC 0214Z 227DEG 41KT 3430 8694 3401 8693 3377 8703

70/DD

Special weather statement, Mar 17, 9:45 PM CDT, 2 hours 18 minutes before

Special Weather Statement
National Weather Service Huntsville AL
945 PM CDT Wed Mar 17 2021

ALZ006>008-016-180315-
Marshall AL-Madison AL-Morgan AL-Cullman AL-
945 PM CDT Wed Mar 17 2021

...SIGNIFICANT WEATHER ADVISORY FOR WESTERN MARSHALL...SOUTHWESTERN
MADISON...NORTHEASTERN CULLMAN AND SOUTHEASTERN MORGAN COUNTIES UNTIL
1015 PM CDT...

At 944 PM CDT, Doppler radar was tracking a broken line of strong
thunderstorms extending from near Priceville to 9 miles north of
Holly Pond to near Blountsville. Movement was to the east at 30 mph.

Pea size hail and wind gusts up to 50 mph will be possible with these
storms.

Locations impacted include...
Albertville, Guntersville, Arab, Redstone Arsenal, Hanceville,
Priceville, Owens Cross Roads, Holly Pond, Morgan City and Douglas.

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.

Very heavy rainfall is also occurring with these storms, and may lead
to localized flooding. Do not drive your vehicle through flooded
roadways.

&&

LAT...LON 3402 8673 3429 8680 3455 8691 3459 8643
      3424 8624 3416 8622 3410 8630 3426 8644
      3425 8652 3412 8660 3412 8663 3409 8666
      3408 8669 3409 8669 3408 8670 3405 8668
      3406 8670 3403 8670
TIME...MOT...LOC 0244Z 279DEG 27KT 3452 8679 3431 8667 3410 8663

70/DD

Special weather statement, Mar 17, 10:13 PM CDT, 1 hour 50 minutes before

Special Weather Statement
National Weather Service Huntsville AL
1013 PM CDT Wed Mar 17 2021

ALZ006-008>010-180400-
Marshall AL-Madison AL-DeKalb AL-Jackson AL-
1013 PM CDT Wed Mar 17 2021

...SIGNIFICANT WEATHER ADVISORY FOR JACKSON...EASTERN MARSHALL...
SOUTHEASTERN MADISON AND DEKALB COUNTIES UNTIL 1100 PM CDT...

At 1012 PM CDT, Doppler radar was tracking a broken line of strong
thunderstorms extending from near Gurley to near Grant to near Boaz.
Movement was east at 70 mph.

Penny size hail and wind gusts up to 50 mph will be possible with
these storms.

Locations impacted include...
Albertville, Scottsboro, Fort Payne, Boaz, Guntersville, Rainsville,
Bridgeport, Henagar, Stevenson and Crossville.

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.

These storms may intensify, so be certain to monitor local radio
stations and available television stations for additional information
and possible warnings from the National Weather Service.

&&

LAT...LON 3448 8558 3444 8558 3437 8563 3436 8566
      3426 8577 3426 8581 3424 8581 3424 8584
      3420 8585 3420 8611 3419 8611 3418 8619
      3413 8627 3447 8633 3483 8646 3498 8561
      3453 8551
TIME...MOT...LOC 0312Z 266DEG 62KT 3479 8638 3450 8626 3417 8620

70/DD

Special weather statement, Mar 17, 11:03 PM CDT, 1 hour before

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Local storm report, Mar 17, 11:22 PM CDT, 41 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
Mar 17, 7:40 PM CDT	Areal Flood Warning	HUN	Colbert, Lauderdale	6 hr
Mar 17, 7:54 PM CDT	Special Weather Statement	HUN	Colbert, Lauderdale	36 min
Mar 17, 8:16 PM CDT	Areal Flood Warning	HUN	DeKalb, Jackson, Madison, Marshall, Morgan	6 hr
Mar 17, 8:17 PM CDT	Special Weather Statement	HUN	Colbert, Franklin	43 min
Mar 17, 8:26 PM CDT	Special Weather Statement	HUN	Lauderdale	34 min
Mar 17, 8:47 PM CDT	Areal Flood Warning	HUN	Madison	11 hr
Mar 17, 8:50 PM CDT	Special Weather Statement	HUN	Colbert, Lauderdale, Lawrence	25 min
Mar 17, 9:06 PM CDT	River Flood Warning	HUN	Lawrence	24 hr
Mar 17, 9:07 PM CDT	Flash Flood Warning	HUN	Colbert, Lauderdale	3 hr
Mar 17, 9:14 PM CDT	Special Weather Statement	HUN	Cullman	31 min
Mar 17, 9:19 PM CDT	Flash Flood Warning	HUN	Jackson, Madison, Marshall, Morgan	3 hr
Mar 17, 9:34 PM CDT	Areal Flood Warning	HUN	DeKalb	6 hr
Mar 17, 9:45 PM CDT	Special Weather Statement	HUN	Marshall, Morgan	30 min
Mar 17, 10:09 PM CDT	Areal Flood Warning	HUN	Cullman, Madison, Morgan	6 hr
Mar 17, 10:13 PM CDT	Special Weather Statement	HUN	DeKalb, Jackson	47 min
Mar 17, 10:44 PM CDT	Tornado Warning	HUN	DeKalb	13 min
Mar 17, 11:03 PM CDT	Special Weather Statement	HUN	DeKalb	27 min
Mar 17, 11:10 PM CDT	Flash Flood Warning Considerable damage threat	HUN	Jackson, Marshall	4 hr
Mar 18, 1:30 AM CDT	Areal Flood Warning	HUN	Cullman, DeKalb, Jackson, Madison, Marshall, Morgan	8 hr
Mar 18, 8:35 AM CDT	Areal Flood Warning	HUN	Madison	2 hr
Mar 18, 10:15 AM CDT	River Flood Warning	HUN	Jackson, Madison, Marshall	67 hr
Mar 18, 10:45 AM CDT	River Flood Warning	HUN	Colbert, Lauderdale	4 days

Nearby

Areal Flood Warnings in Alabama, 2021 Every areal flood 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.