Severe Thunderstorm Warning 18, NWS Birmingham, AL

876 
WWUS54 KBMX 112040
SVSBMX

Severe Weather Statement
National Weather Service Birmingham AL
240 PM CST Sat Jan 11 2020

ALC027-112130-
/O.CON.KBMX.SV.W.0018.000000T0000Z-200111T2130Z/
Clay AL-
240 PM CST Sat Jan 11 2020

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 330 PM CST
FOR CLAY COUNTY...

At 240 PM CST, severe thunderstorms were located along a line
extending from near Mount Cheaha to near Goodwater, moving east at 45
mph.

HAZARD...70 mph wind gusts.

SOURCE...Radar indicated.

IMPACT...Expect considerable tree damage. Damage is likely to mobile 
         homes, roofs, and outbuildings.

Locations impacted include...
Lineville, Ashland, Barfield, Delta, Cleveland Crossroads, Cragford,
Hollins, Roselle, Lake Chinnabee, Millerville, Mellow Valley,
Gunthertown and Motley.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Tornado Watch remains in effect until 800 PM CST for east central
Alabama.

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

&&

LAT...LON 3311 8566 3311 8597 3309 8598 3309 8601
      3311 8601 3311 8618 3320 8617 3319 8612
      3329 8612 3330 8598 3338 8598 3338 8594
      3340 8592 3350 8590 3350 8585 3347 8589
      3347 8578 3350 8576 3349 8564
TIME...MOT...LOC 2040Z 248DEG 41KT 3354 8578 3304 8596 

HAIL...<.75IN
WIND...70MPH
 
$$

40/Sizemore

016 
WWUS54 KBMX 112057
SVSBMX

Severe Weather Statement
National Weather Service Birmingham AL
257 PM CST Sat Jan 11 2020

ALC027-112130-
/O.CON.KBMX.SV.W.0018.000000T0000Z-200111T2130Z/
Clay AL-
257 PM CST Sat Jan 11 2020

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 330 PM CST
FOR CLAY COUNTY...

At 257 PM CST, severe thunderstorms were located along a line
extending from near Heflin to Goldville, moving east at 45 mph.

HAZARD...70 mph wind gusts.

SOURCE...Radar indicated.

IMPACT...Expect considerable tree damage. Damage is likely to mobile 
         homes, roofs, and outbuildings.

Locations impacted include...
Lineville, Ashland, Delta, Barfield, Cleveland Crossroads, Cragford,
Millerville, Mellow Valley and Motley.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Tornado Watch remains in effect until 800 PM CST for east central
Alabama.

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

&&

LAT...LON 3311 8566 3311 8597 3309 8598 3309 8601
      3311 8601 3347 8583 3347 8578 3350 8576
      3349 8564
TIME...MOT...LOC 2057Z 248DEG 41KT 3361 8559 3311 8577 

HAIL...<.75IN
WIND...70MPH
 
$$

40/Sizemore

434 
WWUS54 KBMX 112112 RRA
SVSBMX

Severe Weather Statement
National Weather Service Birmingham AL
312 PM CST Sat Jan 11 2020

ALC027-112122-
/O.CAN.KBMX.SV.W.0018.000000T0000Z-200111T2130Z/
Clay AL-
312 PM CST Sat Jan 11 2020

...THE SEVERE THUNDERSTORM WARNING FOR CLAY COUNTY IS CANCELLED...
    
The storms which prompted the warning have moved out of the area.
Therefore, the warning has been cancelled.  However gusty winds are
still possible with these thunderstorms.

A Tornado Watch remains in effect until 800 PM CST for east central
Alabama.

To report severe weather, contact your nearest law enforcement
agency. They will relay your report to the National Weather Service
Birmingham.

LAT...LON 3311 8566 3311 8597 3309 8598 3309 8601
      3311 8601 3347 8583 3347 8578 3350 8576
      3349 8564
TIME...MOT...LOC 2111Z 248DEG 41KT 3367 8541 3317 8559 

$$

40/Sizemore

Area Forecast Discussion
National Weather Service Birmingham AL
1124 AM CST Sat Jan 11 2020

.UPDATE...
For 18Z Aviation and mesoscale.

&&

.SYNOPSIS...

Aloft, a potent upper level trough extended from the High Plains
south through Northern Texas. The trough is expected to attain a
more negative tilt later today as it swings northeast over the Mid
South region. To our southeast, an expansive deep-layer ridge was
positioned southwest of Bermuda.

Toward the surface, a cold front extended from Southeast Canada
southwest through Michigan and further south through the Central
Ohio River Valley into West Tennessee and through West-Central
Mississippi down to the Gulf Coast.

05

&&

.SHORT TERM...
/Updated at 0940 AM CST Sat Jan 11 2020/

1. Mesoscale Update

Watch Status...

A second tornado watch is in effect until 4 pm CST for areas
toughly along and west of Interstate 65 along with St. Clair
County but not including Montgomery County at this time. The
existing tornado watch for 5 northwest counties of Marion,
Winston, Lamar, Fayette and Walker remains in effect until 1 pm
CST.

Current Situation...

A line of strong to severe storms now extend from Northwest
Alabama south just east of the Alabama/Mississippi border.

Mesoscale Model Initialization and Verification...

Comparing RAP soundings to observations the T/Td fields appear to
be running about 3 degrees too cold on temperature and around 1
degree too dry for dew points. Adjusting the point forecast
soundings at MEI and CBM are indicating much higher instability
values than depicted by the model, on the order of 30-50% higher
surface-based instability values. This is being exhibited by
recent deep convective development ahead of the line in South-
Central Mississippi west of Meridian.

Environmental Conditions...

KBMX NEXRAD VAD VWP wind profiler data along with our latest 15Z
BMX sounding both indicate a highly sheared environment with 0-1
km Storm relative helicity values from 250-350 m2/s2. Wind shear
remains robust and is more than sufficient to support severe
storms capable of producing high winds and embedded tornadoes in
the line along with in any discrete convection that can develop
ahead of the line.

The convective line is being dynamically forced and will pose the
broadest concern for high winds. Surface-based instability values
are currently the limiting factor for supporting robust
development ahead of the forced line of storms.

Higher instability (Surface-Based Convective Available Potential
Energy, SBCAPE) values around 500 J/kg per mesonanalysis data was
over our far southwest counties and is expected to advance north
and northeast with time through mid morning. As aforementioned,
our analysis of data shows that these model-derived soundings are
running slightly cooler and drier compared to observations and
accounting for these issues results in SBCAPE values closer to the
700-1100 J/kg range. As the low-level instability continues to
increase and further moistening aloft in the mid levels should
help to further steepen lapse rates and reduce the weak capping in
place over the area.

Activity continues to gradually grow upscale with embedded
rotations and bowing segment indications from radar. Damaging
straight- line winds and damage from embedded tornadoes in the
line is possible and this potential has been increasing over the
past hour or two as surface-based instability has been surging
north from our southwest.

Special Soundings...

We have completed the 12Z and 15Z soundings. There are nearby
showers contaminating our local warm sector environment. We will
wait until we get back into more pristine warm sector conditions
ahead of the line to launch another sounding so we can capture the
actual instability present ahead of the line of storms.

2. Forecast

Today and Tonight.

Expect the potent upper level trough to quickly swing northeast
into the Central Ohio River Valley towards midnight tonight while
shortwave ridging rapidly builds eastward into the Central Plains
region tonight.

The surface cold front will push through the state today,
becoming positioned across western Georgia this evening while
expanding high pressure across Eastern Texas will build into the
Mid South Region overnight.

The concern remains with severe weather today ahead of an intense
line of convective storms that will plow east across the entire
area today. High winds and strong shear in the low to mid levels
will be more than sufficient to support damaging straight-line
winds along with tornadoes both embedded in the line of storms and
in any discrete convection that can develop. The best potential
for this will be later this morning through the afternoon for any
discrete convection to potentially form ahead of the line. Outside
of convection, strong gradient winds will continue to support
potential wind gusts 30-40 mph and potentially higher values in
the higher terrain east and northeast. The relative fast movement
of this system will help to limit flood potential but minor
flooding in urban and low-lying areas will remain possible and
river flooding will remain possible, especially across our western
counties.

Expect decreasing gradient winds as we move into this evening as
the front clears the area while the upper-level dynamics pull
rapidly north of the region. Lingering showers will remain
possible though becoming more and more confined to our far eastern
counties before midnight as drier air filters in from the west.

Unseasonably warm conditions are forecast today with highs in the
low to mid 70's ahead of the front. Temperatures will fall
quickly tonight with readings in the upper 30's far northwest to
values in the low 50's far southeast.

05

.LONG TERM...
/Updated at 0244 AM CST Sat Jan 11 2020/

Sunday through Friday.

The frontal boundary will stall just to our south by Sunday
morning and then begin to lift back to the north by the afternoon.
This boundary will remain draped across the region through
Wednesday as there really is not a big push to get it out. Will
need to keep an eye on rainfall totals through the period as we
could definitely see rises in our river basins. Finally a cold
front and short wave trough will move through Wednesday night and
get the system to finally exit stage right.

This pattern really looks more like a late spring one, with
enough instability for thunderstorm development especially during
the afternoon hours, somewhat enhanced deep layer shear but weaker
low- level shear, and enhanced mid-level lapse rates but a lack
of a synoptic focus. So there will be some potential for stronger
storms with gusty winds/hail and possibly marginal severe threats,
though confidence this far out is low. Two possible periods to
watch would be late Monday afternoon/Monday night, and then ahead
of a frontal passage Wednesday when shear increases. Some locally
heavy rainfall would be possible as well. There still some
uncertainties with the models so will continue to mention some
small rain chances through Friday. Another strong storm system
will work into the region next Saturday and will need to monitor
for any potential severe weather with it.

16

&&

.AVIATION...
18Z TAF Discussion.

Hazardous flying conditions through late afternoon as a line of
strong to severe storms moves west to east across the area. A few
isolated supercells may develop ahead of the line and pose a
damaging wind and tornado risk in addition to the higher damaging
wind and tornado risk from the line of storms.

Expect conditions to improve as the line passes with most of the
TS activity confined to within 50 or so miles on either side of
the line. SHRA is expected to linger behind the line through much
of the afternoon.

A tightening pressure gradient will continue to produce gusty
low-level winds 25-35 kts outside of convection with gusts
potentially over 60 kts with the strongest convection. LLWS will
also persist through early evening as the low-level jet and strong
mid level jet continue to move across the Tennessee Valley
region.

Low-level winds and wind shear will gradually wane with time from
west to east late this afternoon and evening. TS potential will
decrease sufficiently generally 2-4 hours behind the line to not
mention.

Skies will remain BKN/OVC at most sites overnight. Low-level
winds should remain up to discourage notable decreases in
visibility but potentially could occur especially west and south.
CIG's could decrease toward the end of the period south as the
front stalls to our southeast overnight and starts to return north
as a warm front through the day Sunday.

05

&&

.FIRE WEATHER...

A strong storm system will impact the area through this evening
with widespread rainfall expected. Look for strong winds on
Saturday as well with gusts up to 40 mph. Dry conditions return
overnight, but rain chances return in the southeast Sunday
afternoon with high rain chances through at least mid-week. There
are no fire weather concerns at this time.

&&

.PRELIMINARY POINT TEMPS/POPS...
Gadsden     73  44  65  46  67 / 100  40  10  40  60
Anniston    74  46  69  50  69 / 100  40  10  50  70
Birmingham  72  44  67  49  67 / 100  20  10  40  60
Tuscaloosa  75  44  67  47  67 /  90  10  10  40  60
Calera      72  45  66  49  67 / 100  20  10  50  70
Auburn      71  48  68  57  70 / 100  60  30  70  70
Montgomery  76  47  70  57  72 / 100  40  20  70  70
Troy        76  50  72  59  73 / 100  50  40  70  60

&&

.BMX WATCHES/WARNINGS/ADVISORIES/...
Wind Advisory until 9 PM CST this evening for the following
counties: Autauga...Barbour...Bibb...Blount...Bullock...
Calhoun...Chambers...Cherokee...Chilton...Clay...Cleburne...
Coosa...Dallas...Elmore...Etowah...Fayette...Greene...Hale...
Jefferson...Lamar...Lee...Lowndes...Macon...Marengo...Marion...
Montgomery...Perry...Pickens...Pike...Randolph...Russell...
Shelby...St. Clair...Sumter...Talladega...Tallapoosa...
Tuscaloosa...Walker...Winston.

&&

Hazardous Weather Outlook
National Weather Service Birmingham AL
443 AM CST Sat Jan 11 2020

ALZ011>015-017>050-121345-
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-
443 AM CST Sat Jan 11 2020

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

.DAY ONE...Outlook through Tonight.

Severe storms are likely for all of Central Alabama today between 7
AM in the northwest and 7 PM in the southeast. Threats include
damaging winds up to 70 mph and tornadoes, some of which could be
strong.

Strong winds are also occurring ahead of the line of storms, with
sustained winds of 15 to 25 mph gusting to 30 to 45 mph. Higher
gusts will be possible at higher elevations.

Rainfall of 1 to 2 inches, with locally higher amounts, will occur
today. This may aggravate river levels or cause some localized
flooding where the heaviest rates occur.

.DAYS TWO THROUGH SEVEN...Sunday through Friday.

Rainfall will cause rises on the Tombigbee River, with levels rising
above flood stage at the Bevill Lock and Dam Sunday and Monday.

.SPOTTER INFORMATION STATEMENT...

Activation of storm spotters and emergency management will likely
be needed today.

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE BIRMINGHAM AL
155 PM CST SAT JAN 11 2020

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

0138 PM     TSTM WND DMG     WESTOVER                33.35N 86.54W
01/11/2020                   SHELBY             AL   EMERGENCY MNGR

            TREES DOWN ON US 280 AND HIGHWAY 51.

&&

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE BIRMINGHAM AL
157 PM CST SAT JAN 11 2020

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

0115 PM     TSTM WND DMG     4 W BROOKSVILLE         34.20N 86.54W
01/11/2020                   BLOUNT             AL   PUBLIC

            TREES DOWN.

0145 PM     TSTM WND DMG     1 N CLANTON             32.85N 86.63W
01/11/2020                   CHILTON            AL   PUBLIC

            TREES DOWN.

0151 PM     TSTM WND DMG     1 SW GOODYEAR-GADSDEN   34.00N 85.98W
01/11/2020                   ETOWAH             AL   PUBLIC

            TREES DOWN.

&&

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE BIRMINGHAM AL
201 PM CST SAT JAN 11 2020

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

1223 PM     TSTM WND DMG     1 S OAK GROVE           33.45N 87.16W
01/11/2020                   JEFFERSON          AL   EMERGENCY MNGR

            TREES DOWN AT RILEY CIRCLE ON LOCK 17 RD
            NEAR OAK GROVE.

&&

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE BIRMINGHAM AL
205 PM CST SAT JAN 11 2020

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

0140 PM     TSTM WND DMG     2 W GADSDEN             34.02N 86.03W
01/11/2020                   ETOWAH             AL   EMERGENCY MNGR

            TREE ON HOUSE ON CANSLER AVE IN GADSDEN.

&&

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE BIRMINGHAM AL
208 PM CST SAT JAN 11 2020

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

0110 PM     TSTM WND DMG     1 SSW HENDRIX           34.03N 86.46W
01/11/2020                   BLOUNT             AL   EMERGENCY MNGR

            TREE DOWN ON ROADWAY ALONG 254 KING ROAD IN
            ONEONTA.

&&

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE BIRMINGHAM AL
209 PM CST SAT JAN 11 2020

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

0148 PM     TSTM WND DMG     1 N CLANTON             32.85N 86.63W
01/11/2020                   CHILTON            AL   PUBLIC

            TREES AND POWER LINES DOWN.

0150 PM     TSTM WND DMG     2 E CLANTON             32.85N 86.59W
01/11/2020                   CHILTON            AL   PUBLIC

            TREES DOWN.

0207 PM     TSTM WND DMG     COLUMBIANA              33.18N 86.61W
01/11/2020                   SHELBY             AL   EMERGENCY MNGR

            WIDESPREAD REPORTS OF TREES DOWN ACROSS THE
            COUNTY. NUNEROUS POWER OUTAGES.

&&