Alert archive / Alabama / Severe Thunderstorm Warnings in 2017

Severe Thunderstorm Warning 95, NWS Birmingham, AL

April 5, 2017Shelby County, Alabama

NWS Birmingham, AL issued this severe thunderstorm warning at Apr 5, 2017, 11:55 AM CDT for Shelby County, Alabama. It was in force for 66 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: Apr 5, 2017, 11:55 AM CDT (16:55 UTC)
Expired: Apr 5, 2017, 1:01 PM CDT
In force: 66 min
Issued by: NWS Birmingham, AL
Area: Storm-based polygon
Hail: 1.0 in
Wind: 60.0 mph

County Shelby County, AL

The radar

The Birmingham radar (KBMX), 26 km from the middle of the area, began a volume at 16:54 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

Time	Report	Where	Remark
Apr 5, 12:17 PM CDT	HAIL 0.5	Alabaster, AL	DIME SIZED HAIL IN ALABASTER.
Apr 5, 12:25 PM CDT	HAIL 0.5	Pelham, AL	DIME SIZED HAIL REPORTED.
Apr 5, 12:45 PM CDT	TSTM WND DMG	Chelsea, AL	TREE DOWN ON HOUSE. ESTIMATED 40-50 MPH WINDS.

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

Did it verify

Verified. The Iowa Environmental Mesonet's Cow matched one storm report to this severe thunderstorm warning; the first came 50 minutes after it went out.

Cow counts a report within 15 km of the polygon while the warning was in force: a tornado for a tornado warning; hail of 1 inch or more, a gust of 58 mph or more or wind damage for a severe thunderstorm warning; a flash flood report for a flash flood warning.

The watch it was issued in

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

Issued	Product	Office	Lasted
Apr 5, 6:54 AM CDT	Tornado Watch	SPC	8 hr

The nearest sounding before it

Birmingham, AL (KBMX), launched 12:00Z, 4.9 hours before the alert went out and 26 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: 560 J/kg
Mixed-layer CIN: -102 J/kg
Mixed-layer LCL: 617 m above ground
0-6 km bulk shear: 68 kt
0-1 km storm-relative helicity: 408 m²/s²
0-3 km storm-relative helicity: 396 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 2.6

Open this sounding in Storm Lab

The text

As transmitted.

716 
WUUS54 KBMX 051655
SVRBMX
ALC117-051815-
/O.NEW.KBMX.SV.W.0095.170405T1655Z-170405T1815Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Birmingham AL
1155 AM CDT WED APR 5 2017

The National Weather Service in Birmingham has issued a

* Severe Thunderstorm Warning for...
  Shelby County in Alabama...

* Until 115 PM CDT

* At 1154 AM CDT, a severe thunderstorm was located near Tannehill
  Ironworks State Park, or 12 miles northwest of Montevallo, moving
  northeast at 45 mph.

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

  SOURCE...Radar indicated. 

  IMPACT...Hail damage to vehicles is expected. Expect wind damage 
           to roofs, siding, and trees. 

* Locations impacted include...
  Birmingham, Hoover, Alabaster, Pelham, Helena, Leeds, Chelsea,
  Columbiana, Wilsonville, Indian Springs Village, Vincent,
  Harpersville, Westover, Oak Mountain State Park, Vandiver, Maylene,
  Oak Mountain Amphitheater, Greystone, Highland Lakes and
  Riverchase.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3350 8648 3350 8640 3339 8638 3335 8634
      3334 8637 3329 8636 3328 8643 3326 8643
      3314 8697 3317 8703 3324 8703 3328 8693
      3333 8689 3333 8683 3342 8675 3342 8672
      3347 8667 3347 8661 3355 8652 3355 8648
TIME...MOT...LOC 1654Z 245DEG 40KT 3320 8704 

HAIL...1.00IN
WIND...60MPH
 
$$

25/Owen

2 follow-up statements

354 
WWUS54 KBMX 051729
SVSBMX

Severe Weather Statement
National Weather Service Birmingham AL
1229 PM CDT WED APR 5 2017

ALC117-051815-
/O.CON.KBMX.SV.W.0095.000000T0000Z-170405T1815Z/
Shelby AL-
1229 PM CDT WED APR 5 2017

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 115 PM CDT
FOR NORTHEASTERN SHELBY COUNTY...

At 1228 PM CDT, a severe thunderstorm was located over Highland 
Lakes, or over Chelsea, moving northeast at 45 mph.

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

SOURCE...Radar indicated. 

IMPACT...Hail damage to vehicles is expected. Expect wind damage to 
         roofs, siding, and trees. 

Locations impacted include...
Birmingham, Hoover, Pelham, Leeds, Chelsea, Columbiana, Wilsonville,
Indian Springs Village, Vincent, Harpersville, Westover, Highland
Lakes, Oak Mountain State Park, Fowler Lake, Vandiver, Lake Purdy,
Greystone, Meadowbrook, Mount Laurel and Sterrett.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3350 8648 3350 8640 3339 8638 3335 8634
      3334 8637 3329 8636 3328 8643 3326 8643
      3320 8670 3330 8677 3336 8677 3342 8675
      3342 8672 3347 8667 3347 8661 3355 8652
      3355 8648
TIME...MOT...LOC 1728Z 245DEG 40KT 3336 8662 

HAIL...1.00IN
WIND...60MPH
 
$$

25/Owen

321 
WWUS54 KBMX 051801
SVSBMX

Severe Weather Statement
National Weather Service Birmingham AL
101 PM CDT WED APR 5 2017

ALC117-051811-
/O.CAN.KBMX.SV.W.0095.000000T0000Z-170405T1815Z/
Shelby AL-
101 PM CDT WED APR 5 2017

...THE SEVERE THUNDERSTORM WARNING FOR NORTHEASTERN SHELBY COUNTY IS
CANCELLED...
        
The storm which prompted the warning has moved out of the area.
Therefore the warning has been cancelled.

LAT...LON 3350 8648 3350 8640 3339 8638 3335 8634
      3334 8637 3329 8636 3328 8643 3326 8643
      3320 8670 3330 8677 3336 8677 3342 8675
      3342 8672 3347 8667 3347 8661 3355 8652
      3355 8648
TIME...MOT...LOC 1801Z 245DEG 40KT 3351 8624 

$$

25/Owen

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 Birmingham, AL wrote its last area forecast discussion before this severe thunderstorm warning went out at Apr 5, 9:04 AM CDT, 2 hours 51 minutes earlier.

Area forecast discussion, Apr 5, 9:04 AM CDT, 2 hours 51 minutes before

Area Forecast Discussion
National Weather Service Birmingham AL
904 AM CDT Wed Apr 5 2017

.UPDATE...
MESOSCALE UPDATE.

&&

.DISCUSSION...

Effective warm front roughly positioned from northern Sumter
County northeast across southern Bibb County east across southern
Talladega County and into southern Cleburne County.

The airmass is continuing to rapidly destabilize south of the warm
front with temperatures in the low to mid 70's along the U.S.
Highway 80 corridor along with dew points in the lower 70's
across our southern tier of counties.

We continue to monitor the potential for large hail with
thunderstorms near and north of the warm front and for the
increasing potential of all convective hazards to the southwest
across southern Alabama.

Our concern continues to increase with discrete storms moving out
of Clarke and Monroe Counties and into Wilcox County while
additional discrete storms are moving out of Escambia and Conecuh
Counties and into Covington County. These storms will pose a
threat to Selma/Montgomery/Troy areas through the next few hours.

Visible satellite imagery indicates some breaks in the clouds from
Washington County north to Tuscaloosa County. Solar radiation will
help to further raise temperatures and will result in further
airmass destabilization through the remainder of the morning
hours across our western and southwest counties.

The latest derived hodograph from the KBMX radar velocity wind
profile indicates 0-6 km bulk shear of 54 knots and 0-1 km storm
relative helicities of 108 m2/s2. The environment remains
supportive of severe thunderstorms and tornadoes south of the warm
front.

05

&&

.AVIATION...
12Z TAF Discussion.

For the north the main focus will be the storms that will develop
and continue to develop over the area through at least 18Z. Went
with predominate thunderstorms for all northern sites during that
time. Went with VCTS for southern sites. Will continue to be a
complicated pattern for the next 12 hours. Finally after 3 to 6Z
the pattern will improve.

16

&&

.FIRE WEATHER...

A storm system will bring rain and thunderstorms to the area
through tonight. Rain-free weather returns Thursday through the
weekend. Critical fire weather conditions are not expected through
the next 7 days.

&&

.PRELIMINARY POINT TEMPS/POPS...
Gadsden     78  46  61  40  62 / 100  50  20  10   0
Anniston    79  47  61  40  63 / 100  60  20  10   0
Birmingham  79  46  62  43  63 / 100  30  20  10   0
Tuscaloosa  80  46  65  43  65 / 100  30  10   0   0
Calera      80  47  63  43  64 /  80  30  10  10   0
Auburn      78  49  62  42  62 /  80  60  10  10   0
Montgomery  81  50  68  44  66 /  80  60  10   0   0
Troy        81  51  66  43  65 /  80  60  10   0   0

&&

.BMX WATCHES/WARNINGS/ADVISORIES/...
None.

&&

Hazardous weather outlook, Apr 5, 5:05 AM CDT, 6 hours 50 minutes before

Hazardous Weather Outlook
National Weather Service Birmingham AL
505 AM CDT Wed Apr 5 2017

ALZ011>015-017>050-061315-
Marion-Lamar-Fayette-Winston-Walker-Blount-Etowah-Calhoun-Cherokee-
Cleburne-Pickens-Tuscaloosa-Jefferson-Shelby-St. Clair-Talladega-
Clay-Randolph-Sumter-Greene-Hale-Perry-Bibb-Chilton-Coosa-Tallapoosa-
Chambers-Marengo-Dallas-Autauga-Lowndes-Elmore-Montgomery-Macon-
Bullock-Lee-Russell-Pike-Barbour-
505 AM CDT Wed Apr 5 2017

This Hazardous Weather Outlook is for the counties served by the
National Weather Service office in Birmingham.

.DAY ONE...Outlook Through Tonight.

Severe thunderstorms will be possible through tonight.

Round one of severe storms will be associated with a warm front as
it lifts northward through the area. The warm front will move north
of the area by 11 AM. Large hail up to the size of baseballs and
damaging winds will continue to be the dominate concerns of these
storms.

South of the warm front, isolated to scattered storms will develop
and continue to move northeast through the afternoon. This activity
will impact all of Central Alabama. Destructive and long-track
tornadoes will be possible, along with hail up to the size of
baseballs, and damaging straight line winds. These threats will
encompass all of Central Alabama with the greatest threat area along
and east of a line from Warrior to West Blocton to Uniontown.

Round three will be the along the cold front itself as it slides
through the area. Storms may develop along the line and continue to
develop through 9 PM or until the front slides east of the area.
Large hail, damaging winds and tornadoes will be be possible along
this line as well.

.DAYS TWO THROUGH SEVEN...Thursday through Tuesday.

No hazardous weather is expected at this time.

.SPOTTER INFORMATION STATEMENT...

Activation of storm spotters and emergency management is expected
from early Wednesday morning through Wednesday evening.

In the hours before

Local storm report, Apr 5, 9:43 AM CDT, 2 hours 12 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE BIRMINGHAM AL
943 AM CDT WED APR 5 2017

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0610 AM     TSTM WND DMG     ROSELLE                 33.19N 86.05W
04/05/2017                   CLAY               AL   EMERGENCY MNGR

            TREE DOWN BLOCKING ROADWAY. COUNTY ROAD 7
            JUST SOUTH OF HIGHWAY 148. ESTIMATED 40-50
            MPH WINDS. TIME ESTIMATED.

&&

JH

Local storm report, Apr 5, 9:59 AM CDT, 1 hour 56 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE BIRMINGHAM AL
959 AM CDT WED APR 5 2017

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0741 AM     TSTM WND DMG     1 WNW HIGHLAND LAKES    33.39N 86.66W
04/05/2017                   SHELBY             AL   BROADCAST MEDIA

            TREE DOWN BLOCKING WESTOVER ROAD NEAR OLD
            HIGHWAY 280. ESTIMATED 40-50 MPH WINDS.

&&

JH

Local storm report, Apr 5, 10:14 AM CDT, 1 hour 41 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE BIRMINGHAM AL
1014 AM CDT WED APR 5 2017

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

1000 AM     HEAVY RAIN       OXFORD                  33.61N 85.84W
04/05/2017  M2.95 INCH       CALHOUN            AL   PUBLIC

            RAIN TOTAL SO FAR.

&&

JH

Local storm report, Apr 5, 10:35 AM CDT, 1 hour 20 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE BIRMINGHAM AL
1035 AM CDT WED APR 5 2017

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

1025 AM     HAIL             2 SSW HOPE HULL         32.25N 86.37W
04/05/2017  M1.00 INCH       MONTGOMERY         AL   TRAINED SPOTTER

&&

JH

Local storm report, Apr 5, 11:02 AM CDT, 53 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE BIRMINGHAM AL
1102 AM CDT WED APR 5 2017

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0610 AM     TSTM WND DMG     3 NNW ASHLAND           33.32N 85.85W
04/05/2017                   CLAY               AL   EMERGENCY MNGR

            PORCH REMOVED FROM HOME DUE TO HIGH WINDS.
            TIME ESTIMATED BY RADAR.

&&

JH

Local storm report, Apr 5, 11:09 AM CDT, 46 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE BIRMINGHAM AL
1109 AM CDT WED APR 5 2017

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

1031 AM     HAIL             1 ESE EASTDALE MALL     32.38N 86.19W
04/05/2017  E0.25 INCH       MONTGOMERY         AL   TRAINED SPOTTER

&&

JH

The office that day

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

Issued	Product	Office	Counties	Lasted
Apr 5, 1:24 AM CDT	Severe Thunderstorm Warning	BMX	Barbour	66 min
Apr 5, 2:04 AM CDT	Severe Thunderstorm Warning	BMX	Barbour, Pike	56 min
Apr 5, 2:44 AM CDT	Severe Thunderstorm Warning	BMX	Russell	32 min
Apr 5, 3:32 AM CDT	Severe Thunderstorm Warning	BMX	Russell	43 min
Apr 5, 3:35 AM CDT	Severe Thunderstorm Warning	BMX	Hale, Perry	40 min
Apr 5, 3:54 AM CDT	Severe Thunderstorm Warning	BMX	Bibb, Tuscaloosa	34 min
Apr 5, 3:57 AM CDT	Severe Thunderstorm Warning	BMX	Autauga, Lowndes, Montgomery	33 min
Apr 5, 4:11 AM CDT	Severe Thunderstorm Warning	BMX	Bibb, Perry	49 min
Apr 5, 4:45 AM CDT	Severe Thunderstorm Warning	BMX	Chilton, Shelby	44 min
Apr 5, 5:22 AM CDT	Severe Thunderstorm Warning	BMX	Calhoun, Clay, Cleburne, Talladega	38 min
Apr 5, 5:24 AM CDT	Severe Thunderstorm Warning	BMX	Chambers, Tallapoosa	51 min
Apr 5, 6:02 AM CDT	Severe Thunderstorm Warning	BMX	Clay, Randolph	58 min
Apr 5, 6:04 AM CDT	Severe Thunderstorm Warning	BMX	Bibb, Hale, Perry	56 min
Apr 5, 6:52 AM CDT	Severe Thunderstorm Warning	BMX	Shelby	83 min
Apr 5, 7:22 AM CDT	Areal Flood Advisory	BMX	Greene, Pickens, Sumter, Tuscaloosa	3 hr
Apr 5, 7:40 AM CDT	Areal Flood Advisory	BMX	Blount, Jefferson	3 hr
Apr 5, 8:43 AM CDT	Areal Flood Advisory	BMX	Calhoun, St. Clair, Shelby, Talladega	3 hr
Apr 5, 9:00 AM CDT	Severe Thunderstorm Warning	BMX	Dallas, Lowndes	75 min
Apr 5, 9:13 AM CDT	Special Weather Statement	BMX	Cleburne	32 min
Apr 5, 9:35 AM CDT	Severe Thunderstorm Warning	BMX	Barbour, Pike	70 min
Apr 5, 10:16 AM CDT	Severe Thunderstorm Warning	BMX	Montgomery	29 min
Apr 5, 10:29 AM CDT	Areal Flood Advisory	BMX	Calhoun, Clay, Cleburne, Randolph	3 hr
Apr 5, 10:38 AM CDT	Severe Thunderstorm Warning	BMX	Elmore, Macon, Tallapoosa	67 min
Apr 5, 10:56 AM CDT	Severe Thunderstorm Warning	BMX	Barbour	49 min
Apr 5, 11:43 AM CDT	Severe Thunderstorm Warning	BMX	Bibb, Tuscaloosa	32 min
Apr 5, 12:53 PM CDT	Special Weather Statement	BMX	Talladega	82 min
Apr 5, 1:42 PM CDT	Special Weather Statement	BMX	Cleburne	33 min
Apr 5, 2:35 PM CDT	Special Weather Statement	BMX	Cleburne	25 min
Apr 5, 3:03 PM CDT	Special Weather Statement	BMX	Talladega	42 min
Apr 5, 3:22 PM CDT	Severe Thunderstorm Warning	BMX	St. Clair, Talladega	38 min
Apr 5, 3:48 PM CDT	Severe Thunderstorm Warning	BMX	Calhoun, Cleburne, Talladega	67 min
Apr 5, 4:08 PM CDT	Tornado Warning	BMX	Cleburne	52 min
Apr 5, 4:10 PM CDT	Severe Thunderstorm Warning	BMX	Calhoun, Cherokee, Etowah	45 min
Apr 5, 4:37 PM CDT	Wind Advisory	BMX	Autauga, Barbour, Bibb, Blount, Bullock, Calhoun and 33 more	26 hr
Apr 5, 4:59 PM CDT	Special Weather Statement	BMX	Randolph	46 min
Apr 5, 5:30 PM CDT	Severe Thunderstorm Warning	BMX	Jefferson, Shelby	45 min
Apr 5, 5:32 PM CDT	Special Weather Statement	BMX	Randolph	13 min
Apr 5, 5:33 PM CDT	Special Weather Statement	BMX	Randolph, Tallapoosa	57 min
Apr 5, 5:55 PM CDT	Severe Thunderstorm Warning	BMX	Chilton, Shelby	35 min
Apr 5, 5:56 PM CDT	Severe Thunderstorm Warning	BMX	St. Clair	40 min
Apr 5, 6:03 PM CDT	Severe Thunderstorm Warning	BMX	Randolph	27 min
Apr 5, 6:17 PM CDT	Severe Thunderstorm Warning	BMX	Calhoun, St. Clair, Talladega	43 min
Apr 5, 6:20 PM CDT	Special Weather Statement	BMX	DeKalb	25 min
Apr 5, 6:32 PM CDT	Severe Thunderstorm Warning	BMX	St. Clair, Shelby, Talladega	27 min
Apr 5, 6:35 PM CDT	Severe Thunderstorm Warning	BMX	Etowah	25 min

Nearby

Severe Thunderstorm Warnings in Alabama, 2017 Every severe thunderstorm 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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.