Flash Flood Warning 2, NWS Birmingham, AL

Area Forecast Discussion
National Weather Service Birmingham AL
743 PM CDT Sat Apr 14 2018

.UPDATE...
MESOSCALE UPDATE.

&&

.SHORT TERM...

There remains a slight risk of severe weather across parts of
Central Alabama, generally east of a line from Selma to Clanton to
Anniston. The threats include a small chance of a tornado and
damaging winds.

SBCAPE values have dropped to around 500, but are up to 1500 just
south of Dallas County. Helicity and Bulk Shear values remain
high. There is a chance that once this thunderstorms line south of
the area gets moving again, some of the additional thunderstorms
may get into our southeast and east areas. A Tornado Watch is in
effect for Dallas and Lowndes County this evening.

High precipitable water values, strong low level winds and
therefore moisture transport, and good convergence will keep
showers and thunderstorms going across much of Central Alabama
this evening. The threat of Flash Flooding continues, especially
in the higher rain rate areas. Rainfall totals of 3-4 inches are
expected with higher isolated totals.

Overall changes include keeping the severe threat mentioned east
and southeast, and expanding the time frame back to 2-3am far
southeast.

75

Previous short-term discussion:Today through Sunday.

Confidence continues to increase in the threat for severe storms
this afternoon into tonight. Models have been trending slightly
slower and more toward a neutral and eventually negative tilt with
the upper-level trough as it moves toward the Mississippi River
Valley. These small changes should result in lower surface pressures
along the cold front with stronger backing of surface winds as a
QLCS approaches from the west. The slower timing should also allow
SBCAPE values to increase into the range of 1500-2500 J/kg across
the western half of Alabama before storms arrive. A QLCS with a
sizable damaging wind and tornado threat appears likely particularly
west of a line from Gadsden to Montgomery. A couple of strong
tornadoes (EF2-EF3) cannot be ruled out along and northwest of a
line from Demopolis to Birmingham, where forecast hodographs
indicate 0-1km shear of 30-40kt with clockwise curvature. This
potential may be associated with a couple of isolated supercells
ahead of or embedded within the QLCS. The threat should gradually
diminish across our eastern areas as the convective line loses
forward momentum and moves into weaker instability during the
evening and overnight hours. The severe threat will probably end
around 2 AM in our southeastern counties.

The passage of a cold front will bring cooler conditions for Sunday.
Rainfall should exit into Georgia during the morning hours, leading
to a somewhat breezy and cool afternoon.

87/Grantham

.LONG TERM...
Sunday Night through Saturday

Drying conditions will be in place Sunday night as cold air
advection again returns to the area. Temperatures will be in the 30s
and low 40s again with the coldest temperatures in the north. Lows
on Tuesday morning will be chilly as well with 30s and 40s possible.
Will need to watch the trends for frost potential each morning, but
right now Tuesday morning looks to be the better chance with lighter
winds.

An extended period of dry and tranquil weather is expected through
the upcoming workweek. The only slight chance of rain may come
Wednesday afternoon and evening as a moisture-starved front moves
through. Models are indicating a little bit more moisture now, so
will stick with 20 to 30 PoPs. Our next weather system should arrive
the following weekend. Models are not as impressive with this
system, but it will be one to watch as we get closer to the time
frame.

16

&&

.AVIATION...
00Z TAF Discussion.

Large area of showers and thunderstorms cover Central Alabama.
Terminal forecast have mention of showers, some heavy at times,
through the overnight hours. Thunder was mentioned at
ANB/ASN/MGM/TOI. Ceilings will be chaotic, starting off with a mix
of VFR/MVFR and lowering as a cold front approaches. Have IFR
mentioned at the northern sites by daybreak, with MVFR south.
Winds will also be veering with time starting off variable to
southerly, then west to northwest by daybreak. Some improvement in
the ceilings north back to MVFR is anticipated during the late morning
hours behind the front.

75

&&

.FIRE WEATHER...

Showers and storms will slide through the area today, tonight, and
Sunday morning. Strong to severe storms are possible during the
afternoon and evening as the system progresses from west to east.
Drier Monday and Tuesday. There are no fire weather concerns at this
time.

&&

.PRELIMINARY POINT TEMPS/POPS...
Gadsden     54  59  37  60  36 / 100  50  10   0   0
Anniston    56  61  37  60  37 / 100  60  10   0   0
Birmingham  53  60  40  62  41 / 100  30   0   0   0
Tuscaloosa  50  61  39  64  40 / 100  10   0   0   0
Calera      52  61  39  62  41 / 100  30   0   0   0
Auburn      60  62  40  61  41 / 100  90   0   0   0
Montgomery  55  64  40  65  41 / 100  50   0   0   0
Troy        57  64  41  65  41 / 100  70   0   0   0

&&

.BMX WATCHES/WARNINGS/ADVISORIES/...
Flash Flood Watch until 1 AM CDT Sunday for the following
counties: Autauga...Bibb...Blount...Calhoun...Chilton...Coosa...
Dallas...Etowah...Fayette...Greene...Hale...Jefferson...Lamar...
Lowndes...Marengo...Marion...Perry...Pickens...Shelby...St.
Clair...Sumter...Talladega...Tuscaloosa...Walker...Winston.

&&

Hazardous Weather Outlook
National Weather Service Birmingham AL
727 PM CDT Sat Apr 14 2018

ALZ011>015-017>050-160330-
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-
727 PM CDT Sat Apr 14 2018

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

.DAY ONE...Tonight.

Damaging winds and tornadoes will remain a threat tonight. The
threat area is generally along and east of a line from Gadsden to
Childersburg to Selma. To the west of this line, the severe threat
has ended. The threat will diminish from west to east and should exit
the eastern counties by 3 AM.

Rainfall amounts of 3 to 4 inches could lead to isolated flash
flooding into tonight. The best chance of flash flooding will
generally be west of a line from Gadsden to Montgomery.

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

Due to heavy rainfall, minor river flooding is expected Sunday
through Wednesday in the Tombigbee and Sucarnoochee River basins.

.SPOTTER INFORMATION STATEMENT...

Activation of storm spotters and emergency management will continue
to be necessary through around 3 AM.

Special Weather Statement
National Weather Service Birmingham AL
636 PM CDT SAT APR 14 2018

ALZ021-027-028-150000-
Clay AL-Talladega AL-Cleburne AL-
636 PM CDT SAT APR 14 2018

...SIGNIFICANT WEATHER ADVISORY FOR EAST CENTRAL TALLADEGA...
SOUTHWESTERN CLEBURNE AND NORTHEASTERN CLAY COUNTIES UNTIL 700 PM
CDT...

At 636 PM CDT, Doppler radar was tracking strong thunderstorms along
a line extending from near Waldo to near Ashland. Movement was
northeast at 35 mph.

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

Locations impacted include...
Oxford, Munford, Anniston Regional Airport, Grant Town, Delta, Mount
Cheaha, Camp Mac, Ironaton, Jenifer, Lake Chinnabee and Gunthertown.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3328 8595 3345 8605 3359 8591 3359 8580
      3356 8579 3356 8574 3348 8564 3343 8564
TIME...MOT...LOC 2336Z 219DEG 32KT 3345 8601 3331 8592

89^GSatterwhite

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE BIRMINGHAM AL
640 PM CDT SAT APR 14 2018

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

1205 PM     TSTM WND DMG     1 WSW FOWLER'S CROSSROA 33.79N 87.68W
04/14/2018                   FAYETTE            AL   BROADCAST MEDIA

            TREE DOWN ON HOUSE AND TRUCK.

&&

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE BIRMINGHAM AL
702 PM CDT SAT APR 14 2018

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

0525 PM     TSTM WND DMG     1 SW NOCCALULA FALLS    34.03N 86.05W
04/14/2018                   ETOWAH             AL   EMERGENCY MNGR

            TREE ON HOUSE.

&&

Special Weather Statement
National Weather Service Birmingham AL
740 PM CDT SAT APR 14 2018

ALZ019>021-150100-
Calhoun AL-Cleburne AL-Cherokee AL-
740 PM CDT SAT APR 14 2018

...SIGNIFICANT WEATHER ADVISORY FOR NORTHEASTERN CALHOUN...
NORTHEASTERN CLEBURNE AND SOUTHEASTERN CHEROKEE COUNTIES UNTIL 800 PM
CDT...

At 740 PM CDT, Doppler radar was tracking a strong thunderstorm near
Piedmont, moving northeast at 55 mph.

Pea size hail and winds in excess of 40 mph will be possible with
this storm.

Locations impacted include...
Piedmont, Pleasant Gap, Mars Hills, Liberty Hill, Oak Level, Borden
Springs and Spring Garden.

LAT...LON 3376 8550 3392 8567 3408 8544 3406 8542
      3383 8537
TIME...MOT...LOC 0040Z 222DEG 48KT 3387 8551

89^GSatterwhite

Special Weather Statement
National Weather Service Birmingham AL
850 PM CDT SAT APR 14 2018

ALZ040-150215-
Dallas AL-
850 PM CDT SAT APR 14 2018

...SIGNIFICANT WEATHER ADVISORY FOR CENTRAL DALLAS COUNTY UNTIL 915
PM CDT...

At 850 PM CDT, Doppler radar was tracking a strong thunderstorm near
Dannelly Reservoir, or 15 miles north of Camden, moving northeast at
55 mph.

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

Locations impacted include...
Selma, Selmont-West Selmont, Orrville, Bogue Chitto, Old Cahaba Park,
Memorial Stadium, Dannelly Reservoir, Dallas County Horse Arena,
Potter Station, Skyharbor Airport, Whites Bluff, Safford, Hazen,
Craig Field Aiport, Selma Drag Strip, Edmund Pettus Bridge,
Crumptonia and Selma University.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Torrential rainfall is also occurring with this storm, and may lead
to localized flooding. Do not drive your vehicle through flooded
roadways.

&&

LAT...LON 3214 8725 3215 8728 3217 8729 3216 8730
      3218 8732 3220 8732 3220 8736 3222 8738
      3222 8739 3224 8739 3224 8740 3225 8742
      3249 8718 3249 8713 3236 8695 3212 8726
TIME...MOT...LOC 0150Z 222DEG 49KT 3222 8730

89^GSatterwhite

Special Weather Statement
National Weather Service Birmingham AL
913 PM CDT SAT APR 14 2018

ALZ033-040-150300-
Dallas AL-Perry AL-
913 PM CDT SAT APR 14 2018

...SIGNIFICANT WEATHER ADVISORY FOR EAST CENTRAL PERRY AND
NORTHEASTERN DALLAS COUNTIES UNTIL 1000 PM CDT...

At 913 PM CDT, Doppler radar was tracking a strong thunderstorm over
Old Cahaba Park, or near Selmont-West Selmont, moving northeast at 45
mph.

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

Locations impacted include...
Selma, Valley Grande, Selmont-West Selmont, Gardner Island, Paul M
Grist State Park, Old Cahaba Park, Memorial Stadium, Burnsville,
Dallas County Horse Arena, Potter Station, Skyharbor Airport,
Summerfield, Craig Field Aiport, Valley Creek Junction,
Plantersville, Selma Drag Strip, Edmund Pettus Bridge, Selma
University and Barrett Creek.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Torrential rainfall is also occurring with this storm, and may lead
to localized flooding. Do not drive your vehicle through flooded
roadways.

&&

LAT...LON 3240 8727 3268 8704 3268 8702 3266 8702
      3266 8692 3257 8690 3254 8691 3249 8688
      3248 8689 3246 8686 3244 8687 3244 8685
      3243 8684 3225 8705
TIME...MOT...LOC 0213Z 222DEG 39KT 3235 8711

89^GSatterwhite