Special Weather Statement, NWS Atlanta, GA

Area Forecast Discussion
National Weather Service Peachtree City GA
201 PM EDT Wed Jul 18 2018

.PREV DISCUSSION... /Issued 1032 AM EDT Wed Jul 18 2018/

UPDATE...
The forecast is in good shape this morning and the area is off to
a quiet start. A quick sfc analysis reveals a frontal boundary
situated across the CWA. This boundary may make it slightly
further south by this afternoon before stalling. Given its
presence across the CWA...it is expected to the primary focus for
convection this afternoon and evening as daytime heating peaks.
Convection will be most likely in the vicinity of the frontal
boundary and areas southward. Similar to the previous
forecast...this still looks to be in the CSG to MCN vicinity and
southward...tho may need to show higher POPs closer to ATL metro
where hi-res CAMs still suggest at least isolated activity.

Kovacik

PREV DISCUSSION... /Issued 715 AM EDT Wed Jul 18 2018/

PREV DISCUSSION... /issued 335 AM EDT Wed Jul 18 2018/

SHORT TERM /Today through Thursday/...

The short term period begins with a tranquil morning and shower
activity abating along frontal boundary. Front will continue to
sink south through today with some mid level drier air working in
its wake. Focus will decidedly be in the CSG to MCN areas and
points southward where precipitable water will be well in excess
of 2 inches and there is instability near 2000 J/KG. This should
be more than enough to warrant likely pops for the southern tier
although should be mainly heavy rainers with continued warm mid
level temps.

The big question will be the transition zone near the Atlanta
metro as to how much dry air works into the area and does this
shut off pops completely. Although there is no doubt PWs will
drop off, still could see 1.75 in values which should be
supportive of isolated pops at a minimum. This is supported well
by the NAMNest which shows activity firing along i20 after 18Z.

As weak low forms along stalled boundary for Thu, this will allow
deep moisture return back northward. Cutoff for likely pops will
roughly be over the same zone but mid range scattered pops will be
much further north along I85. Some cooler mid level temps along
the transition zone over North GA, so may see potential for
slightly increased strong to isolated severe storms.

Deese

LONG TERM /Thursday Night through Tuesday/...

Extended forecast period continues to look somewhat unsettled,
especially the beginning as a fairly high amplitude upper-level
pattern evolves. By Friday, region comes under increasing
northwesterly flow aloft as eastern U.S. upper low deepens. Saturday
still appears to be an active weather day as a fairly strong short
wave sweeps through the base of the upper low driving a surface cold
front into the state. Moderately unstable atmosphere and
strengthening mid-level winds combine with the enhanced lift for what
looks to be a good chance for organized, strong to severe
convection.

Some drier air tries to push in from the northwest behind this
system, however persistent weak upper troughing across the eastern
U.S. and a lingering surface boundary across the region should keep
chance POPs going into the middle of next week.

20

&&

.AVIATION...
18Z Update...
Convection has begun to initiate across central Georgia this
afternoon...and a TEMPO remains in place for CSG and MCN into the
evening. Will watch trends for metro ATL and AHN sites over the
next few hours but for now think VCSH should handle it. VFR
conditions are expected into the overnight. Some indication MVFR
to perhaps IFR cigs with some fog will develop but that will be
somewhat dependent on today's convection. For now will only keep
sub-VFR cigs across MCN and AHN where best moisture looks to exist.
Should see regular cu field again Thursday with better chance for
convection. Winds will remain mainly NW this afternoon and
evening tho could flirt with NE at times. Predominant shift to NE
should hold off until about 06-08z timeframe and then remain on
the east side. Speeds should remain under 7kts today but increase
to 7-10kts Thursday.

//ATL Confidence...18Z Update...
Medium on convective potential today.
Medium on overnight cig trends.
High on all other elements.

Kovacik

&&

.PRELIMINARY POINT TEMPS/POPS...
Athens          90  72  87  71 /  30  30  60  40
Atlanta         91  74  88  72 /  30  30  50  30
Blairsville     86  65  82  67 /  30  20  50  30
Cartersville    91  70  89  71 /  20  10  50  30
Columbus        92  75  91  74 /  60  40  50  40
Gainesville     89  71  86  70 /  30  30  50  30
Macon           91  73  89  73 /  60  40  60  50
Rome            91  69  90  71 /  10  10  30  30
Peachtree City  91  72  89  71 /  30  30  50  30
Vidalia         91  74  88  73 /  60  60  70  60

&&

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

SHORT TERM...Deese
LONG TERM....20
AVIATION...Kovacik

Hazardous Weather Outlook
National Weather Service Peachtree City GA
1214 PM EDT Wed Jul 18 2018

GAZ001>009-011>016-019>025-027-030>039-041>062-066>076-078>086-
089>098-102>113-191615-
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-
1214 PM EDT Wed Jul 18 2018

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

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

Scattered to numerous thunderstorms are expected across central
Georgia this afternoon and tonight. Isolated thunderstorms are
possible across the north. The main hazard will be locally heavy
rainfall. Heavy rainfall could cause temporary street flooding and
ponding of water in low lying areas.

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

Scattered to numerous thunderstorms are expected Thursday through
Tuesday. A few strong to severe thunderstorms will be possible each
day with strong, gusty winds, frequent lightning, and very heavy
rainfall. A strong storm system approaching the region Friday and
moving across the area Saturday will increase the chances for severe
thunderstorms those two days.

.SPOTTER INFORMATION STATEMENT...

Spotter activation is not requested but spotters are encouraged to
submit reports of severe weather through the web by going to
weather.gov/atlanta.

Special Weather Statement
National Weather Service Peachtree City GA
313 PM EDT WED JUL 18 2018

GAZ110-111-181945-
Wheeler GA-Telfair GA-
313 PM EDT WED JUL 18 2018

...SIGNIFICANT WEATHER ADVISORY FOR SOUTHERN WHEELER AND EASTERN
TELFAIR COUNTIES UNTIL 345 PM EDT...

At 313 PM EDT...a strong thunderstorm was over Towns, or 8 miles
southeast of McRae...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 this storm include
McRae, Lumber City, Scotland, Towns, Jordan and Spring Hill.

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 3188 8287 3206 8288 3211 8262 3210 8261
      3208 8262 3207 8261 3203 8261 3200 8258
      3195 8257 3193 8259 3194 8260 3192 8263
      3192 8268 3191 8268 3190 8269 3190 8270
      3189 8271 3187 8275
TIME...MOT...LOC 1913Z 267DEG 10KT 3198 8279

WIND...40MPH