Special Weather Statement, NWS Atlanta, GA

Area Forecast Discussion
National Weather Service Peachtree City GA
350 PM EDT Wed Apr 19 2017

.SHORT TERM /Tonight through Thursday Night/...
Limiting factor for convection thus far today has been the
abundance of low clouds in place. Models had done a poor job in
developing and maintaining these clouds so stands to reason they
would do a poor job in initializing storm formation today which
has been several hours delayed.

Once clouds decided to scatter though...they scattered quickly
allowing for a quick warmup. Most sites remain a few degrees from
convective temp for today but that should be no issue here soon.
CAPE values on mesoanalysis already pushing 1500 to 2000 J/KG from
East Central Alabama through the metro and should serve as the
focus for storm initiation here soon.

Downdraft CAPE remains modest at best within the wedge with only
conducive values for strong winds to the south where storms will
not be as prevalent. Still cant rule out downburst winds with
isolated cells but hail will be the primary threat with the
stronger activity given continued coolish temps aloft.

Wedge breaks down through Thu with Bermuda ridge building at the
surface from the SE. This will allow for some drier air for the
northern tier with PW values falling below an inch from Macon
southward. This will leave the best chances which will be slight
chance to low end chance at best for the northern tier where CAPE
will be sufficient for storms but relatively weak activity given
expected 500 to 1000 J/KG values.

Deese

.LONG TERM /Friday through Wednesday/...
No major changes made to the extended forecast. The long term
starts with the 500mb ridge having nosed over the area and little
in the way of significant precip is expected Thursday night into
Wed morning.

A weak cold front moves into n Ga on Friday with the best
precip chances over n GA with only lighter rainfall amounts
expected. N GA will again have the best precip chances on Saturday
with the GFS producing light rainfall amounts and the European
is basically dry. This is mostly due to the GFS having the next
surface low a little farther east than the European.

Saturday night and Sunday is when the next significant period
of heavy weather is expected as the GFS is only a little faster
than the European bringing a strong cold front into n and w GA
around 12z Sunday and moving across the rest of the forecast area
on Sunday. A rather strong positively tilted upper trough and Jet
is associated with the system with 30-40 kts of low level shear
forecast from the GFS and 500-1000 surface based cape at the start
of Saturday night over the far nw. The low level shear weakens
overnight and is not too strong for Sunday as the front moves
across the area. The potential for Severe storms will continue
to be monitored.

Storm potential looks to have ended for Sunday night with just
chance to slight chance for showers Sunday night into Monday
associated with the upper trough/Low moving across the area.

At this point...Tuesday will be dry.

Temperatures will continue above normal Sunday then cooling
to within a few degrees of normal through Tuesday.

BDL/01

&&

.AVIATION...
18Z UPDATE...

After extensive low clouds this morning...really in the last 30
min starting to see some significant clearing across the metro
sites and especially down south. This will give way to a Sct cu
deck initially but will become BKN rather quickly with TSRA
formation possible. Axis of best development still in question
but somewhere southwest of ATL looks like a good bet and then
moving across ATL terminals through 22Z or so. Once this activity
pushes through...should see more tranquil conditions for the
remainder of the TAF period. Shift to west still looks on track
for 14Z for the winds.

//ATL CONFIDENCE...18Z UPDATE...
Medium on TSRA timing.
High on remaining elements.

Deese

&&

.PRELIMINARY POINT TEMPS/POPS...
Athens          60  84  61  86 /  30  20  20  30
Atlanta         62  82  64  83 /  20  20  20  20
Blairsville     56  77  56  78 /  30  30  30  40
Cartersville    61  83  61  82 /  20  30  30  30
Columbus        64  86  64  85 /   5  10  10  10
Gainesville     60  81  62  82 /  30  30  30  30
Macon           60  85  60  86 /  10   5   5  10
Rome            61  84  60  83 /  20  30  30  40
Peachtree City  59  83  60  85 /  10  10  10  10
Vidalia         61  85  62  86 /  10  10  10  10

&&

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

SHORT TERM...Deese
LONG TERM....01
AVIATION...Deese

Hazardous Weather Outlook
National Weather Service Peachtree City GA
505 AM EDT Wed Apr 19 2017

GAZ001>009-011>016-019>025-027-030>039-041>062-066>076-078>086-
089>098-102>113-201000-
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-
505 AM EDT Wed Apr 19 2017

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

.DAY ONE...Today and Tonight...

Isolated to scattered thunderstorms are possible over north
and portions of central Georgia...mainly this afternoon and
evening. A few thunderstorms may be strong with Gusty Winds...
Small Hail...Frequent Lightning and Locally Heavy Rain.

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

There will be a chance of thunderstorms over mainly north
Georgia Thursday into Saturday. There is some potential for
severe thunderstorms Saturday Night and Sunday.

No Hazardous weather is expected at this time Monday and
Tuesday.

.SPOTTER INFORMATION STATEMENT...

Spotter activation will not be needed through tonight.

Special Weather Statement
National Weather Service Peachtree City GA
549 PM EDT WED APR 19 2017

GAZ052-066-192215-
Troup GA-Heard GA-
549 PM EDT WED APR 19 2017

...SIGNIFICANT WEATHER ADVISORY FOR NORTHWESTERN TROUP AND
SOUTHWESTERN HEARD COUNTIES UNTIL 615 PM EDT...

At 549 PM EDT...a strong thunderstorm was over Glenn, or 8 miles
northeast of Stroud...moving north 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
Franklin, Waresville, Glenn and Texas.

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 3327 8509 3306 8513 3306 8522 3327 8526
TIME...MOT...LOC 2149Z 187DEG 7KT 3312 8520

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