Special Weather Statement, NWS Atlanta, GA

Area Forecast Discussion
National Weather Service Peachtree City GA
737 PM EDT Wed Aug 19 2020

.PREV DISCUSSION... /issued 348 PM EDT Wed Aug 19 2020/

SHORT TERM /Tonight through Thursday Night/...
Primary concern in the short term period is heavy rainfall/
isolated flash flooding and diurnal convection. PW on KFFC morning
RAOB was only 1.3in and 19Z RAP analysis 1.4in over all but far SE
counties, yet deep convection in north GA so far today have been
very efficient and moving just fast enough for some training/
redevelopment with favorable orientation and boundary interaction.
PW progged to increase significantly to 1.75-1.85in this time
tomorrow. Only hope for not seeing enhanced heavy rainfall and
flooding threat is if clouds will diminish sfc heating and
instability, which is a strong possibility. Vertical wind shear
will be limited as well, so storms should be less intense
Thursday. Guidance also indicating that convection Thurs night
will persist past midnight, which is also very possible if deep
moisture materializes to the extent forecast. Tried to modify
max/min temps to decrease diurnal range but NBM max temps already
quite cool tomorrow.

SNELSON

LONG TERM /Friday through Wednesday/...
Wet weekend ahead as the long term picks up on Friday with stalled,
sheared PV anomaly and associated 500 mb trough axis still to the
west of the CWA. Broad ascent is forecast to continue to
overspread the region focused in part by any vorticity maxima
rotating around the trough as well as general WAA the the low
levels which will also be bringing in plenty of gulf moisture.
Models are supportive of likely or higher PoPs across the region
both Friday and Saturday, though final coverage details may be
influenced by mesoscale details, such as remnant outflow
boundaries and leftover cloudiness from previous day's/overnight
convection, that courser global models won't properly resolve.
700-500 mb lapse rates will remain rather lack luster on Friday,
though ample day time heating and marginal shear will support some
strong thunderstorm potential. Lapse rates improve a bit on
Saturday as colder core of trough is expected to rotate through
the CWA on its way to being absorbed within polar jet, making for
somewhat better CAPE profiles and decent shear profiles, so some
potential will once again exist for stronger thunderstorms across
the area, though plenty of uncertainty remains with regards to
timing as well as placement of aforementioned mesoscale features
that could disrupt the larger scale set up.

Trough begins to dissipate on Sunday as PV anomaly gets sheared
out between large, persistent western ridge and another ridge
sliding in from the Atlantic. Still, plenty of moisture will be
wrapping into the CWA thanks to being on the western flank of that
Atlantic ridge, so while PoPs may not be as prolific, still
expect typical summer like coverage across the north, and possibly
even better coverage to the south thanks to outflows and
seabreeze type fronts. Similar situation on Monday, though more
uncertainty begins to creep into the forecast. 12Z GFS shows
tropical wave moving into the gulf during this time period.
Location of this tropical wave will be highly dependent on how
organized current system over the MDR of the tropical Atlantic
becomes as well as details of the ridge sliding to the west over
the Atlantic. Will carry this uncertainty in the PoPs, though
still expect some coverage given tropical airmass will still be in
place across the CWA.

Lusk

&&

.AVIATION...
00Z UPDATE...

Line of TSRA sliding past ATL are terminals at this hour but still
affecting AHN which will require a continued TEMPO group. Feel
activity will remain north of CSG and MCN through this evening and
will not include any mention of TS there. A brief period of IFR
possible toward daybreak Thu and will continue the mention in the
TAF. Have converted the predominant TSRA to SHRA for Thu afternoon
and then a Prob30 for TSRA. Winds look to remain on the east side
and generally light.

//ATL CONFIDENCE...00Z UPDATE...

Medium on IFR potential.
High on remaining elements.

Deese

&&

.PRELIMINARY POINT TEMPS/POPS...
Athens          68  84  68  81 /  50  80  80  70
Atlanta         69  83  70  80 /  60  80  80  70
Blairsville     63  78  64  74 /  50  80  80  80
Cartersville    68  85  69  80 /  60  80  80  70
Columbus        70  88  71  83 /  50  80  80  70
Gainesville     67  82  68  79 /  50  80  80  70
Macon           70  87  71  82 /  50  80  80  60
Rome            67  85  69  81 /  60  80  70  70
Peachtree City  67  84  69  79 /  60  80  80  70
Vidalia         71  89  72  85 /  40  70  70  60

&&

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

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

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.

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE PEACHTREE CITY GA
743 PM EDT WED AUG 19 2020

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

0620 PM     TSTM WND DMG     2 SW MOUNT BETHEL       33.94N  84.44W
08/19/2020                   COBB               GA   911 CALL CENTER

            A TREE WAS REPORTED DOWN IN THE 3900 BLOCK OF PAPER
            MILL ROAD SE.

&&

EVENT NUMBER FFC2001166

LREAVES

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

GAZ050-200015-
Greene GA-
745 PM EDT Wed Aug 19 2020

...SIGNIFICANT WEATHER ADVISORY FOR GREENE COUNTY UNTIL 815 PM EDT...

At 745 PM EDT...a strong thunderstorm was over Carey, or over
Greensboro...moving north at 10 mph.

  HAZARD...40 to 50 mph wind...nickel 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
Greensboro and Carey.

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 3351 8318 3352 8326 3362 8332 3366 8320
      3359 8307
TIME...MOT...LOC 2345Z 192DEG 8KT 3356 8323

HAIL...0.88IN
WIND...50MPH

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

GAZ039-200015-
Wilkes GA-
747 PM EDT Wed Aug 19 2020

...SIGNIFICANT WEATHER ADVISORY FOR WILKES COUNTY UNTIL 815 PM EDT...

At 747 PM EDT...a line of strong thunderstorms was along a line
extending from near Floral Hill to near Celeste...and moving west at
10 mph.

  HAZARD...40 to 50 mph wind...up to penny 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
Washington, Rayle, Newtown and Celeste.

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 3377 8260 3366 8280 3365 8281 3365 8283
      3379 8289 3388 8266
TIME...MOT...LOC 2347Z 073DEG 7KT 3381 8267 3374 8281

HAIL...0.75IN
WIND...50MPH

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

GAZ052-053-066-067-200030-
Coweta GA-Troup GA-Heard GA-Meriwether GA-
758 PM EDT Wed Aug 19 2020

...SIGNIFICANT WEATHER ADVISORY FOR SOUTHERN COWETA...NORTHEASTERN
TROUP...NORTHEASTERN HEARD AND NORTHWESTERN MERIWETHER COUNTIES UNTIL
830 PM EDT...

At 758 PM EDT...a line of strong thunderstorms was along a line
extending from near Powers Crossroads to near Haralson...and moving
northeast at 10 mph.

  HAZARD...Heavy rain.

  IMPACT...Heavy rain may cause temporary street flooding especially
           in poor drainage areas.

Some locations in the path of these storms include
Newnan, Franklin, Senoia, Grantville, Luthersville, Moreland,
Sharpsburg, Turin, Lone Oak, East Newnan, Corinth, Rocky Mount,
Powers Crossroads and Handy.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Motorists should slow down and be prepared for possible loss of
control due to hydroplaning.

LAT...LON 3341 8502 3333 8456 3312 8465 3325 8510
TIME...MOT...LOC 2358Z 235DEG 14KT 3331 8504 3324 8462

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

GAZ050-200045-
Greene GA-
814 PM EDT Wed Aug 19 2020

...SIGNIFICANT WEATHER ADVISORY FOR NORTHWESTERN GREENE COUNTY UNTIL
845 PM EDT...

At 814 PM EDT...a strong thunderstorm was near Penfield, or near
Greensboro...moving north 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 this storm include
Greensboro, Greshamville, Carey and Penfield.

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 3353 8326 3365 8336 3373 8325 3369 8315
      3358 8315
TIME...MOT...LOC 0014Z 177DEG 11KT 3364 8324

WIND...40MPH

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

GAZ038-039-051-200100-
Taliaferro GA-Wilkes GA-Oglethorpe GA-
823 PM EDT Wed Aug 19 2020

...SIGNIFICANT WEATHER ADVISORY FOR NORTHWESTERN TALIAFERRO...
SOUTHWESTERN WILKES AND SOUTHEASTERN OGLETHORPE COUNTIES UNTIL 900 PM
EDT...

At 823 PM EDT...a strong thunderstorm was over Carters Grove, or 9
miles north of Crawfordville...moving north at 10 mph.

  HAZARD...40 to 50 mph wind...up to penny 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
Carters Grove and Philomath.

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 3364 8285 3364 8297 3366 8295 3368 8297
      3368 8298 3369 8299 3369 8301 3376 8304
      3376 8283
TIME...MOT...LOC 0023Z 174DEG 9KT 3369 8295

HAIL...0.75IN
WIND...50MPH