Severe Thunderstorm Warning 332, NWS Atlanta, GA

Area Forecast Discussion...UPDATED
National Weather Service Peachtree City GA
152 PM EDT Wed Aug 19 2020

.UPDATE...
Forecast in pretty good shape. Convection already underway over
north GA and quite vigorous at times. Seeing some basins' QPE
approach 50-75% of 1hr FFG already. This could be a long day and
night based on rich moisture and instability. Still appears even
greater moisture and SHRA/TSRA coverage expected Thurs and Thurs
night which the only blessing may be greater cloud cover reducing
temps and instability tho heavy rain still very likely.

SNELSON

.PREV DISCUSSION... /Issued 749 AM EDT Wed Aug 19 2020/

UPDATE...

12z Aviation update below.

Baker

PREV DISCUSSION... /Issued 427 AM EDT Wed Aug 19 2020/

SHORT TERM /Today through Thursday/...

As upper trough amplifies with axis west of the area today, some
enhanced forcing for convection will be in place along with a
stalled boundary across some central portions of the CWA and
possible influence of another sfc boundary near the NW. The greater
deep layer moisture will be in the northern and western majority so
have trended likely pops to this part of the area with chance pops
elsewhere in the east. Some strong to isolated severe intensity of
diurnally aided storms are possible with marginal conditional
instability.

Progged trough has even more amplification and the axis shifts
farther southward into the Gulf, so region has increased SW fetch
and moisture advection for Thursday. Have likely to categorical pops
accordingly and a bit greater chance for more organized/stronger
convection in central or eastern GA as SW flow/shear increases. SPC
does have parts of central GA in a Day 2 Marginal Risk for severe
potential.

For temps, highs today look to be near climo norms in the upper 80s
to low 90s for most areas, then limited to about 4-5 degrees below
norm (low to mid 80s) for Thursday given aforementioned increased
moisture/convective coverage.

Baker

LONG TERM /Thursday Night through Tuesday/...

The long term period will begin with the deep upper-level trough
centered over the ArkLaMiss, placing Georgia within a region of
deep layer southwesterly flow and broad ascent. Ascent will be
maximized on Friday and Saturday thanks to a somewhat-abnormal-
for-summer 250 mb jet streak across the area. The GFS and ECMWF
are progging a 500 mb cutoff low associated with the trough on
Friday and Saturday, with vort maxima advecting northward out of
the base of the trough as an extra source of lift for showers and
thunderstorms both days. Upper-level dynamics and PWATs of 1.5" to
2" across much of the CWA on Friday will be conducive for
numerous showers and thunderstorms with locally heavy rainfall and
water-loaded downdrafts. The trough will begin to lift on
Saturday as it is forced northward by the Bermuda High expanding
across the Eastern Seaboard. PWATs across the northern CWA will
decrease a bit as a result, but Saturday will still bring numerous
showers and thunderstorms.

By Sunday, much of the CWA will be under the influence of the
Bermuda High, though some moisture advection will continue around
its periphery. Models are hinting at some drier air working into
the CWA on the backside of the lifting trough on Sunday, so I have
chance PoPs across much of north and central Georgia. Moisture
will linger into early next week, though upper-level flow looks to
be unimpressive, so I have chance PoPs for Monday and Tuesday.
Uncertainty remains concerning the impact that Disturbance 1
(currently in the eastern Caribbean Sea) will have on the CWA.
The NHC is forecasting the disturbance to become a tropical
depression late this week or this weekend, so it will need to be
monitored over the coming days.

Martin

&&

.AVIATION...
18Z Update...
Mostly VFR until early Thurs morning with a 1-3hr period of IFR
stratus likely over north GA airports. Sct SHRA/TSRA will become a
bit more widespread after 20Z and persist a bit longer than
normal, thru 03Z. Would not be surprised if isold SHRA/TSRA linger
thru 06Z or later. Sfc winds very light (< 6kts) from the E to SE
thru the period.

//ATL Confidence...18Z Update...
Low-Medium confidence on IFR cig likelihood and timing.
Medium confidence on SHRA/TSRA coverage and timing.
High confidence on all other elements.

SNELSON

&&

.PRELIMINARY POINT TEMPS/POPS...
Athens          88  69  83  67 /  40  50  80  80
Atlanta         87  69  84  68 /  60  60  80  80
Blairsville     80  63  76  63 /  70  50  80  80
Cartersville    88  68  84  68 /  70  60  80  80
Columbus        91  70  87  69 /  60  50  80  80
Gainesville     86  68  80  66 /  60  50  80  80
Macon           90  69  87  68 /  50  50  80  80
Rome            88  68  85  68 /  70  60  80  70
Peachtree City  88  68  84  67 /  60  60  80  80
Vidalia         89  71  88  70 /  40  40  70  70

&&

.FFC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

SHORT TERM...SNELSON
LONG TERM....Lusk
AVIATION...SNELSON

Hazardous Weather Outlook
National Weather Service Peachtree City GA
1224 PM EDT Wed Aug 19 2020

GAZ001>009-011>016-019>025-027-030>039-041>062-066>076-078>086-
089>098-102>113-201630-
Baldwin-Banks-Barrow-Bartow-Bibb-Bleckley-Butts-Carroll-Catoosa-
Chattahoochee-Chattooga-Cherokee-Clarke-Clayton-Cobb-Coweta-
Crawford-Crisp-Dade-Dawson-DeKalb-Dodge-Dooly-Douglas-Emanuel-
Fannin-Fayette-Floyd-Forsyth-Gilmer-Glascock-Gordon-Greene-
Gwinnett-Hall-Hancock-Haralson-Harris-Heard-Henry-Houston-Jackson-
Jasper-Jefferson-Johnson-Jones-Lamar-Laurens-Lumpkin-Macon-
Madison-Marion-Meriwether-Monroe-Montgomery-Morgan-Murray-
Muscogee-Newton-North Fulton-Oconee-Oglethorpe-Paulding-Peach-
Pickens-Pike-Polk-Pulaski-Putnam-Rockdale-Schley-South Fulton-
Spalding-Stewart-Sumter-Talbot-Taliaferro-Taylor-Telfair-Toombs-
Towns-Treutlen-Troup-Twiggs-Union-Upson-Walker-Walton-Warren-
Washington-Webster-Wheeler-White-Whitfield-Wilcox-Wilkes-
Wilkinson-
1224 PM EDT Wed Aug 19 2020

This Hazardous Weather Outlook is for portions of North and Central Georgia.

.DAY ONE...This Afternoon and Tonight...

Scattered to numerous thunderstorms are forecast this afternoon
and evening across north and central Georgia. Some thunderstorms
may linger overnight. A few storms could be strong with an
isolated severe storm possible. The main threats will be locally
heavy rainfall, strong to damaging winds, and cloud-to-ground
lightning.

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

Numerous thunderstorms are expected Thursday through Saturday
across much of the forecast area. Scattered thunderstorms are
forecast Sunday through Tuesday. A few storms could be strong to
severe each day, with strong to damaging winds, frequent
lightning, small hail, and locally heavy rainfall.

.SPOTTER INFORMATION STATEMENT...

Spotter activation will not be needed through tonight.

Special Weather Statement
National Weather Service Peachtree City GA
132 PM EDT Wed Aug 19 2020

GAZ001-002-011-191800-
Chattooga GA-Walker GA-Dade GA-
132 PM EDT Wed Aug 19 2020

...SIGNIFICANT WEATHER ADVISORY FOR NORTHWESTERN CHATTOOGA...WALKER
AND DADE COUNTIES UNTIL 200 PM EDT...

At 132 PM EDT...a line of strong thunderstorms was along a line
extending from Morganville to near Sulpher Springs...and moving east
at 10 mph.

  HAZARD...Up to 40 mph wind...frequent cloud to ground lightning
           and heavy rain.

  IMPACT...Expect minor damage to tree limbs and blowing around of
           light...unsecured objects. Heavy rain may cause temporary
           street flooding especially in poor drainage areas.

Some locations in the path of these storms include
Lafayette, Trenton, Fort Oglethorpe, Chickamauga, Trion, Lookout
Mountain, Center Post, Rising Fawn, Noble, Wildwood, Fairview,
Linwood, Cloudland, Chattanooga  Valley, New England, Morganville,
Hooker, Cloudland Canyon State Park, Cooper Heights and Rock Spring.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

People outdoors should seek shelter immediately. If you can hear
thunder...you are close enough to be struck by lightning. Motorists
should slow down and be prepared for possible loss of control due to
hydroplaning.

LAT...LON 3486 8526 3485 8523 3451 8530 3450 8551
      3476 8556 3498 8553 3498 8526
TIME...MOT...LOC 1732Z 282DEG 10KT 3495 8545 3467 8551

WIND...40MPH

Special Weather Statement
National Weather Service Peachtree City GA
135 PM EDT Wed Aug 19 2020

GAZ007-013-014-021-191800-
Gilmer GA-Dawson GA-Cherokee GA-Pickens GA-
135 PM EDT Wed Aug 19 2020

...SIGNIFICANT WEATHER ADVISORY FOR SOUTHWESTERN GILMER...WESTERN
DAWSON...NORTHWESTERN CHEROKEE AND PICKENS COUNTIES UNTIL 200 PM
EDT...

At 134 PM EDT...a line of strong thunderstorms was along a line
extending from Roundtop to near Talmadge. These storms were nearly
stationary.

  HAZARD...Heavy rain...up to 40 mph wind...and frequent cloud to
           ground lightning.

  IMPACT...Expect minor damage to tree limbs and blowing around of
           light...unsecured objects. Heavy rain may cause temporary
           street flooding especially in poor drainage areas.

Some locations in the path of these storms include
Jasper, Ellijay, Nelson, Waleska, East Ellijay, Talking Rock,
Sequoyah Lake, Talona, Tails Creek, Marblehill, Fausett Lake,
Cartecay, Salacoa Valley, Blaine, Lake Tamarack, Talmadge, Tate, Roy,
Hinton and Roundtop.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

People outdoors should seek shelter immediately. If you can hear
thunder...you are close enough to be struck by lightning. Motorists
should slow down and be prepared for possible loss of control due to
hydroplaning.

LAT...LON 3472 8436 3442 8423 3430 8458 3459 8466
      3469 8465
TIME...MOT...LOC 1734Z 246DEG 2KT 3462 8455 3441 8450

WIND...40MPH

Special Weather Statement
National Weather Service Peachtree City GA
220 PM EDT Wed Aug 19 2020

GAZ013-014-191845-
Dawson GA-Pickens GA-
220 PM EDT Wed Aug 19 2020

...SIGNIFICANT WEATHER ADVISORY FOR WESTERN DAWSON AND NORTHEASTERN
PICKENS COUNTIES UNTIL 245 PM EDT...

At 219 PM EDT...a strong thunderstorm was near Marblehill, or 7 miles
east of Jasper...moving east at 10 mph.

  HAZARD...Up to 40 mph wind...pea sized hail and frequent cloud to
           ground lightning.

  IMPACT...Expect minor damage to tree limbs and blowing around of
           light...unsecured objects.

Some locations in the path of this storm include
Amicalola Falls State Park, Juno and Fausett Lake.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

People outdoors should seek shelter immediately. If you can hear
thunder...you are close enough to be struck by lightning.

LAT...LON 3459 8421 3456 8419 3454 8419 3452 8417
      3449 8415 3438 8420 3444 8434 3454 8435
      3457 8427 3457 8425
TIME...MOT...LOC 1819Z 263DEG 8KT 3448 8430

HAIL...0.25IN
WIND...40MPH

Special Weather Statement
National Weather Service Peachtree City GA
222 PM EDT Wed Aug 19 2020

GAZ002>004-191900-
Whitfield GA-Catoosa GA-Walker GA-
222 PM EDT Wed Aug 19 2020

...SIGNIFICANT WEATHER ADVISORY FOR WHITFIELD...CATOOSA AND EASTERN
WALKER COUNTIES UNTIL 300 PM EDT...

At 222 PM EDT...a line of strong thunderstorms was along a line
extending from Tunnel Hill to near Naomi. These storms were nearly
stationary.

  HAZARD...Up to 40 mph wind...pea sized hail and frequent cloud to
           ground lightning.

  IMPACT...Expect minor damage to tree limbs and blowing around of
           light...unsecured objects.

Some locations in the path of these storms include
Dalton, Varnell, Tunnel Hill, Rocky Face, Mill Creek and Wood
Station.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

People outdoors should seek shelter immediately. If you can hear
thunder...you are close enough to be struck by lightning.

LAT...LON 3495 8484 3468 8506 3470 8524 3491 8510
TIME...MOT...LOC 1822Z 238DEG 3KT 3486 8502 3473 8520

HAIL...0.25IN
WIND...40MPH

Special Weather Statement
National Weather Service Peachtree City GA
224 PM EDT Wed Aug 19 2020

GAZ005>007-012-013-191900-
Gilmer GA-Gordon GA-Pickens GA-Murray GA-Fannin GA-
224 PM EDT Wed Aug 19 2020

...SIGNIFICANT WEATHER ADVISORY FOR WESTERN GILMER...NORTHEASTERN
GORDON...NORTHWESTERN PICKENS...SOUTHEASTERN MURRAY AND NORTHWESTERN
FANNIN COUNTIES UNTIL 300 PM EDT...

At 224 PM EDT...a line of strong thunderstorms was along a line
extending from near Mountaintown to Carters. These storms were nearly
stationary.

  HAZARD...Up to 40 mph wind...pea sized hail and frequent cloud to
           ground lightning.

  IMPACT...Expect minor damage to tree limbs and blowing around of
           light...unsecured objects.

Some locations in the path of these storms include
Chatsworth, Ellijay, Blue Ridge, East Ellijay, Carters, Tails Creek,
Ramhurst, Jones Mill, Higdon, Conasauga Lake, Oakman, Mountaintown,
Fort Mountain State Park, Colwell and Roundtop.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

People outdoors should seek shelter immediately. If you can hear
thunder...you are close enough to be struck by lightning.

LAT...LON 3495 8425 3450 8464 3464 8486 3494 8461
TIME...MOT...LOC 1824Z 255DEG 3KT 3480 8452 3461 8471

HAIL...0.25IN
WIND...40MPH

Special Weather Statement
National Weather Service Peachtree City GA
243 PM EDT Wed Aug 19 2020

GAZ015-016-191915-
White GA-Lumpkin GA-
243 PM EDT Wed Aug 19 2020

...SIGNIFICANT WEATHER ADVISORY FOR WESTERN WHITE AND NORTHEASTERN
LUMPKIN COUNTIES UNTIL 315 PM EDT...

At 243 PM EDT...a strong thunderstorm was over Turners Corner, or 7
miles northwest of Cleveland...moving south at 5 mph.

  HAZARD...Up to 40 mph wind...pea sized hail and frequent cloud to
           ground lightning.

  IMPACT...Expect minor damage to tree limbs and blowing around of
           light...unsecured objects.

Some locations in the path of this storm include
Cleveland, Camp Coleman Lake, Whitley Gap Shelter, Porter Springs,
Turners Corner, Qualatchee Lake and Smithgall Woods Conservation Are.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

People outdoors should seek shelter immediately. If you can hear
thunder...you are close enough to be struck by lightning.

LAT...LON 3470 8396 3472 8378 3460 8373 3457 8387
      3460 8398
TIME...MOT...LOC 1843Z 354DEG 5KT 3465 8388

HAIL...0.25IN
WIND...40MPH