Special Weather Statement, NWS Atlanta, GA

Area Forecast Discussion
National Weather Service Peachtree City GA
754 AM EDT Sun May 20 2018

.PREV DISCUSSION... /Issued 420 AM EDT Sun May 20 2018/

SHORT TERM /Today through Monday/...
A moist airmass will remain across the area.  PWATs of 1 to 1.5
inches this afternoon will increase Monday to 1.5 to 2 inches.
Convection today will once again be isolated to scattered across the
area as weak upper level ridging persists.  A weak upper low over
the FL panhandle by tonight should aid in development to our south
and west and will need to watch west central GA through this
evening.  Have once again opted to keep POPs in the chance category
through this evening, as instability is moderate with little shear.
Any thunderstorms should remain below severe limits, but given the
PWATs cannot rule out locally heavy rainfall with and storm that
does develop. As far as clouds, expect mainly mid and high clouds
this afternoon - mainly over central GA - and should see good
afternoon heating with temperatures near or just above yesterday
high temperatures. Have stayed close to a blend of guidance once
again today.  Light south to southwest winds will prevail.

Overnight, any convection should diminish in coverage and intensity,
with patch fog developing in any areas impacted by heavy showers or
thunderstorms.  As the upper low moves closer to CWA, expect
temperatures over central GA may be a degree or two cooler than
tonight. Light south winds will begin to shift to southeast.

As the upper low treks into east-central AL by tomorrow, rain chance
will increase to good chance/likely over central GA as well as far
north GA.  Cloud cover should be more plentiful, with afternoon
temperatures cooler than yesterday or today.  Southeast winds will
continue near 5 mph.

Atwell

LONG TERM /Monday Night through Saturday/...
Really not expecting much of a pattern change through the extended
forecast period. The long term forecast period now begins Monday
night where a broad scale view of the mid levels reveals a weak
ridge of high pressure in place over the Southeast and lower MS
Valley as a deep closed low digs into the Great Basin region of the
Western US. Despite favoring larger scale forcing for descent
underneath the SE ridge...00z guidance depicts a weak area of mid
level low pressure under the ridge located across SE AL. This
disturbance will likely allow for isolated to scattered
showers/isolated rumbles of thunder to linger across the area late
into the night...esp across southwest portions of the CWA. This low
is expected to slowly meander under the ridge over Georgia Tuesday
and through Wednesday. Although this feature should supply some
degree of additional forcing for ascent for precip...think overall
conditions will be largely diurnal with best coverage during the
afternoon and evening both Tuesday and Wednesday...with isolated
showers continuing into the overnight.

By Thursday...evidence of the weak low becomes less defined with
more of a ridge influence in the mid and upper levels. Unfortunately
the lower level regime will remain largely unchanged as persistent
high pressure over the Atlantic continues to advect a very moist
airmass into the region. This will continue the chance for afternoon
and evening thunderstorms albeit not quite as widespread.

By the end of the week and into the weekend...discrepancy still
exists in regards to the development of low pressure across the
northern Gulf. While both the 00z EC and GFS show some degree of the
remnants of Georgia's early week area of low pressure retrograding
into the Gulf and redeveloping...the EC shows a better influx of
moisture from the Caribbean. Regardless...both models continue to
depict the development of low pressure/troughing in the northern
Gulf. In addition...does not really matter whether the system
becomes tropical or not...it needs to be understood that this system
would have excellent access to deep Gulf moisture and would provide
another mechanism for moderate to heavy precip across the region.
Will need to carefully watch this system given the persistent wet
pattern leading up to its possible development.

Kovacik

&&

.AVIATION...
12Z Update...
Expect scattered VFR to prevail at ATL area & AHN TAF sites
through 19-21Z followed by BKN VFR, with low VFR/high MVFR over
CSG/MCN. Patchy IFR/MVFR visibility possible should improve
quickly (13-14Z)as fog is shallow. Winds will be light, initially
favoring SW-S shifting to S-SE 16-18Z. Wind speeds should remain
below 6kts.

//ATL Confidence...12Z Update...
Medium to high confidence all elements.

Atwell

&&

.PRELIMINARY POINT TEMPS/POPS...
Athens          84  65  82  64 /  40  30  40  40
Atlanta         84  67  79  66 /  50  40  50  40
Blairsville     83  61  79  60 /  50  30  60  40
Cartersville    86  66  81  64 /  50  30  50  50
Columbus        86  68  82  68 /  40  40  60  50
Gainesville     84  65  80  64 /  50  40  40  40
Macon           84  67  82  67 /  40  30  50  50
Rome            88  66  82  65 /  40  20  50  40
Peachtree City  85  66  80  65 /  50  30  50  50
Vidalia         82  68  83  68 /  50  30  40  50

&&

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

SHORT TERM...Atwell
LONG TERM....Kovacik
AVIATION...Atwell

Hazardous Weather Outlook
National Weather Service Peachtree City GA
1150 AM EDT Sun May 20 2018

GAZ001>009-011>016-019>025-027-030>039-041>062-066>076-078>086-
089>098-102>113-210930-
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-
1150 AM EDT Sun May 20 2018

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

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

Scattered thunderstorms are expected across the area this afternoon
and evening. A few storms could be strong with the main hazards
being gusty winds, occasional lightning and locally heavy rainfall.
Areas receiving persistent heavy rainfall could experience localized
flooding, especially along smaller creeks and streams as well as in
low-lying, urban and poorly drained areas.

.DAYS TWO THROUGH SEVEN...Monday through Saturday...

Scattered to numerous thunderstorms can be expected across the area
each day through Saturday. On any given day, A few storms could be
strong with the main hazards being gusty winds, frequent lightning
and heavy rainfall. The best chance for thunderstorms each day will
be during the afternoon and evening hours. Localized flooding will
also be possible where storms remain over an area for prolonged
periods.

.SPOTTER INFORMATION STATEMENT...

Spotter activation is not anticipated, but spotters are encouraged
to summit reports of any severe or significant weather and flooding.

Special Weather Statement
National Weather Service Peachtree City GA
105 PM EDT SUN MAY 20 2018

GAZ005>007-201745-
Gilmer GA-Murray GA-Fannin GA-
105 PM EDT SUN MAY 20 2018

...SIGNIFICANT WEATHER ADVISORY FOR WESTERN GILMER...EASTERN MURRAY
AND NORTHWESTERN FANNIN COUNTIES UNTIL 145 PM EDT...

At 103 PM EDT...strong thunderstorms extended from around Jones Mill
to around Mountaintown, moving south 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 will cause rising
           water on small creeks and streams as well as temporary
           street flooding, especially in poor drainage areas.

Some locations in the path of these storms include
Ellijay, East Ellijay, Conasauga Lake, Carters, Tails Creek, Jones
Mill, Cherry Log, Mountaintown, Higdon and Colwell.

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 3491 8436 3472 8433 3461 8448 3460 8470
      3488 8471 3499 8445 3499 8444
TIME...MOT...LOC 1703Z 004DEG 10KT 3492 8450 3472 8458

WIND...40MPH

Special Weather Statement
National Weather Service Peachtree City GA
202 PM EDT SUN MAY 20 2018

GAZ006-007-014-015-201830-
Gilmer GA-Dawson GA-Lumpkin GA-Fannin GA-
202 PM EDT SUN MAY 20 2018

...SIGNIFICANT WEATHER ADVISORY FOR SOUTHEASTERN GILMER...
NORTHWESTERN DAWSON...WESTERN LUMPKIN AND SOUTHEASTERN FANNIN
COUNTIES UNTIL 230 PM EDT...

At 202 PM EDT...a strong thunderstorm was near Black Gap Shelter, or
14 miles east of Ellijay...moving south at 5 mph.

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

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

Some locations in the path of this storm include
Amicalola Falls State Park, Springer Mountain Shelter, Len Foote Hike
Inn, Black Gap Shelter, Stover Creek Shelter, Nimblewill and Roy.

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 3471 8420 3454 8411 3453 8434 3456 8435
      3456 8437 3455 8438 3470 8436
TIME...MOT...LOC 1802Z 350DEG 7KT 3462 8425

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