Severe Thunderstorm Warning 246, NWS Atlanta, GA

Area Forecast Discussion...UPDATED
National Weather Service Peachtree City GA
226 PM EDT Sat Jul 25 2020

.UPDATE...
Convection firing up quite a bit earlier than expected. Have
tweaked PoPs a little but seem on track now. Received a few
reports of 1 or 2 downed trees and small hail. Wind gusts at
airports and MADIS weather stations remaining below 30kts so far.
Impacts should be isolated but continue through the afternoon and
early evening.

SNELSON

&&

.PREV DISCUSSION... /Issued 726 AM EDT Sat Jul 25 2020/

.Morning Area Forecast Discussion for July 25...

SHORT TERM /Today through Sunday/...

Weakness in the ridging aloft has developed with a weak trough
situated across the CWA. This weak trough aloft will continue
through the remainder of the short term. At the surface, high
pressure will remain in control of the sensible weather through the
short term. However, a surface trough will develop across the
eastern seaboard.

A typical summertime pattern expected today and tomorrow with
afternoon/evening showers and thunderstorms. Convection may try and
develop fist within the weakness of the upper level ridge and then
continue to feed on mesoscale/outflow boundaries throughout the
evening(s). Models have seemed to be overdoing the pops lately, and
not confident enough to go likely at this time. Boundary layer flow
remains very light and slow moving storms will have the potential to
produce locally heavy rainfall. Widespread severe weather is not
anticipated, but an isolated strong/severe thunderstorm cannot be
ruled out. The primary hazards for severe weather would be
gusty/damaging winds and frequent lightning both days.

NListemaa

LONG TERM /Sunday Night through Friday/...

Long term begins Sunday night with anticyclonic rossby wave break in
progress across the eastern third of the CONUS which will elongate
a positive PV anomaly over the western Atlantic into a streamer
that breaks over the southeastern US that will represent a
continued weakness in the 500 mb ridging over the area. Large lobe
of high PV air will dive in behind the wave break, bringing a
broad trough into the Northeast next week that will force a slowly
moving cold front into or just north of the forecast area by
midweek which should act as a focus for increased diurnally driven
PoPs. A subtropical ridge will begin to build over the western
CONUS around which several shortwaves will traverse, which are
forecast to interact with the baroclinic zone left behind by the
front and generate a surface cyclone somewhere to the west of the
CWA. This is forecast to bring decent moisture and rainfall into
the area by the end of the forecast period, though the exact
placement and timing of the cyclone is still uncertain, with a
range of solutions offered by guidance, which ultimately will
determine the extent of impacts to the CWA. Beyond this point,
will need to keep an eye on the tropics, as EPS and operational
Euro as well as some members of the GEFS bring tropical wave that
has emerged into the Atlantic off Africa towards the US, though it
is far, far too early to have faith in any exact track.

One upside to our rainy forecast is a return to more seasonable
temperatures, with forecast highs in the upper 80s to the north with
low to mid 90s toward central Georgia. Plenty of moisture will still
be in place, so heat indices will still be flirting with 100 in some
areas, though it would honestly be more unusual if they were not.
The surface low forecast to form by the end of the week will be able
to tap into the deep moisture across the area, so if best forcing
for lift were to end up over the CWA (which some guidance does
depict), some hefty area wide rainfall totals will be possible,
though as stated above, plenty of uncertainty still remains around
this system.

Lusk

&&

.AVIATION...
18Z Update...
SHRA/TSRA firing up a little earlier than last few days. Adjusted TAFs
in ATL metro and KAHN to show this. Winds will be light E to SE
except near TSRA outflows. Very similar pattern and timing of
clouds and SHRA/TSRA Sunday. Not much chance of MVFR fog/stratus
Sunday morning but possible at KMCN.

//ATL Confidence...18Z Update...
Medium confidence on TSRA timing and MVFR fog/stratus.
High confidence on all other elements.

SNELSON

&&

.PRELIMINARY POINT TEMPS/POPS...
Athens          89  71  91  71 /  40  40  30  20
Atlanta         88  72  89  73 /  40  40  40  20
Blairsville     82  65  83  65 /  40  40  50  20
Cartersville    90  70  91  71 /  40  40  40  20
Columbus        93  73  93  73 /  40  40  40  20
Gainesville     87  70  89  70 /  40  40  40  20
Macon           92  71  93  72 /  40  40  20  20
Rome            91  70  91  71 /  40  40  40  20
Peachtree City  89  70  89  70 /  40  40  40  10
Vidalia         92  73  93  73 /  40  40  30  20

&&

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

SHORT TERM...SNELSON
LONG TERM....Vaughn
AVIATION...SNELSON

Hazardous Weather Outlook
National Weather Service Peachtree City GA
1147 AM EDT Sat Jul 25 2020

GAZ001>009-011>016-019>025-027-030>039-041>062-066>076-078>086-
089>098-102>113-261600-
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-
1147 AM EDT Sat Jul 25 2020

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

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

Scattered thunderstorms are expected to develop over north and
central Georgia this afternoon into the evening. A few storms
could be strong with damaging winds, hail, frequent lightning,
and locally heavy rainfall.

.DAYS TWO THROUGH SEVEN...Sunday through Friday...

Scattered thunderstorms are expected across the area. A few
storms may be strong to severe with damaging winds, frequent
lightning, hail, and locally heavy rainfall.

.SPOTTER INFORMATION STATEMENT...

Spotter activation will not be needed through tonight.

Special Weather Statement
National Weather Service Peachtree City GA
215 PM EDT Sat Jul 25 2020

GAZ034-046>048-251845-
Walton GA-Rockdale GA-Gwinnett GA-Newton GA-
215 PM EDT Sat Jul 25 2020

...SIGNIFICANT WEATHER ADVISORY FOR NORTHWESTERN WALTON...
NORTHEASTERN ROCKDALE...SOUTHEASTERN GWINNETT AND NORTHERN NEWTON
COUNTIES UNTIL 245 PM EDT...

At 215 PM EDT...a strong thunderstorm was over Rosebud, or 9 miles
north of Conyers...moving east at 5 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
Snellville, Loganville, Grayson, Walnut Grove, Jersey, Lakeview
Estates, Windsor, Gum Creek, Youth, Big Haynes Creek Park and
Rosebud.

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 3370 8378 3370 8403 3374 8404 3375 8403
      3377 8405 3382 8407 3394 8386
TIME...MOT...LOC 1815Z 253DEG 6KT 3379 8397

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

Special Weather Statement
National Weather Service Peachtree City GA
221 PM EDT Sat Jul 25 2020

GAZ032-033-043-251845-
North Fulton GA-Douglas GA-Cobb GA-
221 PM EDT Sat Jul 25 2020

...SIGNIFICANT WEATHER ADVISORY FOR NORTH FULTON...NORTHEASTERN
DOUGLAS AND SOUTHWESTERN COBB COUNTIES UNTIL 245 PM EDT...

At 220 PM EDT...a strong thunderstorm was over Mableton, or 7 miles
south of Marietta. This storm was nearly stationary.

  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
Atlanta, Marietta, Douglasville, Smyrna, Powder Springs, Austell,
Lithia Springs, Fair Oaks, Sweetwater Creek State Park, Jim R Miller
Park, Six Flags Over Georgia, Dobbins Air Reserve Base, Mableton and
Vinings.

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 3397 8468 3391 8447 3374 8447 3373 8454
      3375 8457 3372 8460 3371 8471
TIME...MOT...LOC 1820Z 093DEG 3KT 3384 8455

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

Special Weather Statement
National Weather Service Peachtree City GA
222 PM EDT Sat Jul 25 2020

GAZ058>061-071>076-251845-
Butts GA-Jefferson GA-Washington GA-Putnam GA-Monroe GA-Baldwin GA-
Hancock GA-Glascock GA-Jones GA-Jasper GA-
222 PM EDT Sat Jul 25 2020

...SIGNIFICANT WEATHER ADVISORY FOR SOUTHEASTERN BUTTS...JEFFERSON...
WASHINGTON...SOUTHWESTERN PUTNAM...NORTHERN MONROE...BALDWIN...
SOUTHERN HANCOCK...SOUTHWESTERN GLASCOCK...JONES AND SOUTHERN JASPER
COUNTIES UNTIL 245 PM EDT...

At 221 PM EDT...a line of strong thunderstorms was along a line
extending from near Stellaville to near Ethridge to near Turtle
Cove...and moving southwest at 20 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 these storms include
Milledgeville, Sandersville, Jackson, Gray, Monticello, Louisville,
Wrens, Davisboro, Tennille, Flovilla, Stapleton, Avera, Mitchell,
Deepstep, Edge Hill, Edgehill, Midway-Hardwick, Meriwether, Downs and
Beulah.

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 3293 8240 3295 8308 3301 8314 3299 8318
      3297 8316 3298 8321 3296 8327 3295 8326
      3296 8367 3309 8404 3320 8404 3320 8409
      3337 8386 3323 8343 3320 8225
TIME...MOT...LOC 1821Z 038DEG 16KT 3316 8237 3319 8347 3331 8383

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

Special Weather Statement
National Weather Service Peachtree City GA
225 PM EDT Sat Jul 25 2020

GAZ038-050-051-251900-
Taliaferro GA-Oglethorpe GA-Greene GA-
225 PM EDT Sat Jul 25 2020

...SIGNIFICANT WEATHER ADVISORY FOR NORTHWESTERN TALIAFERRO...
SOUTHWESTERN OGLETHORPE AND NORTHEASTERN GREENE COUNTIES UNTIL 300 PM
EDT...

At 225 PM EDT...a strong thunderstorm was near Wrayswood, or 7 miles
northwest of Greensboro. This storm was nearly stationary.

  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
Greensboro, Union Point, Woodville, Maxeys, Robinson, Penfield,
Philomath and Daniel Springs.

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 3374 8298 3358 8297 3359 8329 3377 8328
TIME...MOT...LOC 1825Z 093DEG 3KT 3367 8326

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

Special Weather Statement
National Weather Service Peachtree City GA
226 PM EDT Sat Jul 25 2020

GAZ045-046-251900-
Rockdale GA-DeKalb GA-
226 PM EDT Sat Jul 25 2020

...SIGNIFICANT WEATHER ADVISORY FOR WESTERN ROCKDALE AND SOUTHEASTERN
DEKALB COUNTIES UNTIL 300 PM EDT...

At 226 PM EDT...a strong thunderstorm was over Belmont, or 8 miles
east of Decatur. This storm was nearly stationary.

  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
Clarkston, Stone Mountain, Lithonia, Pine Lake, Belvedere Park,
Candler-Mcafee, Tucker, Belmont, Arabia Mountain, Redan, Panola
Mountain State Park, Snapfinger and Panthersville.

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 3384 8424 3382 8412 3378 8407 3363 8408
      3363 8418 3364 8418 3365 8422 3363 8423
      3363 8424 3365 8425 3365 8426
TIME...MOT...LOC 1826Z 093DEG 3KT 3373 8417

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

Special Weather Statement
National Weather Service Peachtree City GA
241 PM EDT Sat Jul 25 2020

GAZ038-039-050-051-251915-
Taliaferro GA-Wilkes GA-Oglethorpe GA-Greene GA-
241 PM EDT Sat Jul 25 2020

...SIGNIFICANT WEATHER ADVISORY FOR NORTHWESTERN TALIAFERRO...
SOUTHWESTERN WILKES...SOUTHEASTERN OGLETHORPE AND EASTERN GREENE
COUNTIES UNTIL 315 PM EDT...

At 240 PM EDT...a strong thunderstorm was over Lyneville, or near
Crawfordville. This storm was nearly stationary.

  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
Crawfordville, Robinson, Lyneville, Philomath, Alexander Stephens
Park, Sandy Cross, Carters Grove and Daniel Springs.

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 3373 8282 3356 8282 3354 8300 3377 8301
TIME...MOT...LOC 1840Z 093DEG 3KT 3364 8294

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