Special Weather Statement, NWS Atlanta, GA

Area Forecast Discussion
National Weather Service Peachtree City GA
130 PM EDT Mon Aug 6 2018

.UPDATE...

Made a few adjustments to the near-term grids, generally to the
hourly grids to match current diurnal trends. Still expecting
isolated to scattered convection to begin developing shortly, with
best coverage still expected to be across central Georgia and in the
mountains. Still not expecting any widespread severe thunderstorm
threat, however with strong heating, moderate instability and
moderate mid-level lapse rates, a few strong to marginally severe
storms are possible.

20

&&

.PREV DISCUSSION... /Issued 742 AM EDT Mon Aug 6 2018/

UPDATE...
Near term forecast looks good. All overnight precip over middle GA
dissipated around 5 AM this morning so updated forecast to
reflect this. Only did quick update based on observed trends to
catch cool spots this morning but overall forecast on track.

SNELSON

PREV DISCUSSION... /Issued 408 AM EDT Mon Aug 6 2018/

SHORT TERM /Today through Tuesday/...
Main concern in the short term is coverage and intensity of
convection this afternoon/evening and again Tuesday afternoon/
evening. Pattern not expected to change next 36 hours during the
short term period with very weak upper flow in between westerlies to
our north and light easterlies to our south. Based on persistence
from previous two days and hires model guidance, appears coverage
of TSRA will be about the same over north GA this afternoon but a
little higher over middle GA, though this could be skewed by some
hires guidance, such as the NAMnest and one of our local WRF runs
that show a larger area of TSRA over middle GA south of KMCN
persisting into the evening. Like yesterday, some storms this pm
and again Tues pm could become strong with SBCAPE around 2500-3000
J/kg but very weak vertical wind shear. Yesterday's wind reports
on IRIS (which uses nearly all MADIS sites) only showed max wind
gusts of 29 mph or lower, but would not be surprised if isolated
storms see gusts to 40-50 mph.

SNELSON

LONG TERM /Tuesday Night through Sunday/...
The upper level ridge will flatten Wednesday as a weak trough
approaches from the northwest pushing a weakening surface front
across the forecast area. This boundary will focus convection
through the end of the week across the forecast area. Extended
models diverge by the weekend, as far as the upper trough. The
GFS maintains a more progressive solution, sliding the trough axis
over the forecast area while ECMWF develops a cutoff upper level
low around the Mid MS valley, hanging up the passage of the
frontal boundary, which would lead to continued high rain/storm
chances. Either way good chance pops seem reasonable through the
weekend. Guidance temperatures look to be near normal through the
periods and see no reason to deviate.

Atwell

&&

.AVIATION...
18Z Update...

VFR conditions are expected to predominate across the forecast area
through most of this forecast period. Local MVFR or lower
visibilities will develop between 06Z and 14Z, however I do not
anticipate any impacts at the TAF sites at this time. Isolated to
scattered convection is expected, generally between 18Z and and 06Z,
both this afternoon/evening and again tomorrow. Winds will be light
and somewhat variable in direction, generally 6kt or less, but will
favor southwest through northwest.

//ATL Confidence...18Z Update...

Medium on TSRA coverage/likelihood.
High on all other elements

20

&&

.PRELIMINARY POINT TEMPS/POPS...
Athens          93  73  92  73 /  40  20  30  20
Atlanta         92  75  92  74 /  30  20  40  20
Blairsville     88  67  86  67 /  30  20  30  20
Cartersville    93  71  92  72 /  30  20  30  20
Columbus        94  76  93  76 /  30  20  40  20
Gainesville     91  72  90  73 /  30  20  30  20
Macon           94  74  93  74 /  40  30  40  20
Rome            93  72  93  72 /  20  20  30  20
Peachtree City  93  73  92  73 /  30  20  40  20
Vidalia         93  74  92  75 /  50  30  40  20

&&

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

SHORT TERM...20
LONG TERM....26
AVIATION...20

Hazardous Weather Outlook
National Weather Service Peachtree City GA
233 PM EDT Mon Aug 6 2018

GAZ001>009-011>016-019>025-027-030>039-041>062-066>076-078>086-
089>098-102>113-071845-
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-
233 PM EDT Mon Aug 6 2018

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

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

Scattered showers and thunderstorms are expected through this afternoon
and evening. Thunderstorms that do develop could be strong with
gusty winds, dangerous lightning and heavy rain.

.DAYS TWO THROUGH SEVEN...Tuesday through Sunday...

Scattered showers and thunderstorms are expected each day, with
increasing chances Thursday through Sunday. Widespread severe
weather is not anticipated, however, some storms could produce
strong winds, frequent lightning and heavy rain.

.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 or on Twitter by tagging @NWSAtlanta.

Special Weather Statement
National Weather Service Peachtree City GA
245 PM EDT MON AUG 6 2018

GAZ076-061915-
Jefferson GA-
245 PM EDT MON AUG 6 2018

...SIGNIFICANT WEATHER ADVISORY FOR SOUTHEASTERN JEFFERSON COUNTY
UNTIL 315 PM EDT...

At 244 PM EDT...a strong thunderstorm was over Louisville...moving
southwest 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
Louisville, Wadley, Bartow and Moxley.

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 3284 8231 3284 8233 3282 8236 3281 8241
      3280 8242 3283 8251 3288 8252 3292 8251
      3294 8253 3299 8254 3310 8238 3309 8229
      3305 8229 3293 8227
TIME...MOT...LOC 1844Z 043DEG 10KT 3299 8236

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