Severe Thunderstorm Warning 238, NWS Atlanta, GA

Area Forecast Discussion
National Weather Service Peachtree City GA
155 PM EDT Thu Jul 7 2022

...Updated for 18Z Aviation Discussion...

.PREV DISCUSSION... /Issued 1103 AM EDT Thu Jul 7 2022/

..Mid-Morning Update...

UPDATE...

Given trends last night with showers and thunderstorms persisting
well into the overnight hours, have made some tweaks to PoPs to
better reflect chances for lingering convection in an unstable,
very tropical airmass. PWATs on the 12Z sounding were (once
again) around 2.15", close to or exceeding climatological
maximums. SBCAPE of 2500-3000 J/kg is already present areawide, so
when combined with a very moist lower-column, chances remain for
large amounts of mass displacement in explosive initial upward
pulses. A more expansive Slight Risk is in effect across north and
central Georgia today along and north of a line from Rome to
Atlanta and southeastward to the CWA border, highlighting the risk
for damaging winds in the strongest storms that form.

96

SHORT TERM /Today through Friday/...

Another day, another Heat Advisory, another Slight Risk for Severe
Thunderstorms across our northern forecast area, another hot and
muggy day with scattered afternoon showers and thunderstorms.

A stout, stagnant, mid-level ridge remains in place across the
forecast area, but the center of the high pressure circulation will
retrograde further west over the near term which will place the
forecast area in deep, albeit weak, northwest flow. The flattened
out jet stream to the north that we've grown accustomed to will
finally begin to bend through the mid-levels which have allowed some
perturbations to make their way through the main flow. As the
forecast area increasingly sets up in a northwest flow regime, some
of those weak perturbations will begin moving through the forecast
area, setting up triggering mechanism for clusters of showers and
storms to initiate off of (as we've seen through most of the night
so far) and meander towards the southeast along produced outflow
boundaries.

Once again, convection is progged in several CAMs to initialize
later than usual today, allowing temperatures to climb into the mid
to upper 90s with steady dewpoints in the mid 70s. this combination
will produce patchy heat index values over 105 throughout the
forecast area outside the higher elevations, which has prompted a
Heat Advisory through 7 pm. With that said, storms are expected to
initialize earlier than yesterday and have a further areal extent by
mid-afternoon which could bring relief to some areas early, but this
is far from certain as the boundary layer will be extremely hot and
moist (last night's sounding showed a PWAT of 2.18, 0.02 inches from
the daily record per SPC Sounding Climatology), and the slightest
gravity wave could spark convection earlier than expected. Or just
continue it as thunderstorms have yet to cease within the forecast
area at the time of this writing. Additionally, lapse rates should
once again be decent through 3km+, just past the LCL/LFC with the
combination of heat and moisture creating MLCAPE values between 2000-
3000 J/kg by early afternoon. This combination could produce strong
updrafts within any thunderstorms that develop, lofting deep
moisture high within the atmosphere and creating heavy water-loaded
downdrafts and spotty damaging wind gusts. These gusts may be aided
by cold pool mergers within clusters of storms forming on shared
waves/boundaries. the threat for this remains highest across the
northern tier of counties within the forecast area, prompting the
Slight Risk within the Severe Weather Outlook today.

Thiem

LONG TERM /Friday Night through Wednesday/...

Friday evening will likely see ongoing convection across the area
that once again will continue will into the evening and overnight
hours. Northwest flow aloft will bring with it multiple
perturbations that may aid in some broad lift and at the very least
some shear will be in place to allow for some measure of
organization of outflows/cold pools given likely coverage of
convection. Severe parameters aren't through the roof per CAMs, but
the above potential for some organization will allow for a severe
threat to continue well past sunset, alongside potential for flash
flooding for any slower moving storms, especially in urban areas.

Going forward, strong PV anomaly rotates around the base of Canadian
trough with attendant surface cyclone driving cold front into
eastern CONUS Friday into Saturday. High pressure/drier airmass
associated with front will get a bit of an extra kick to the
east/south as anticyclonic wave break on the anticyclonic shear side
of the jet pushes into the Great Plains, all of which should aide in
pushing the front into and possibly through the CWA Saturday into
Sunday. Tropical airmass will likely still be in place for most of
Saturday, leading to another day of diurnal convection and the
possibility of more heat products being needed across all but the
mountainous counties. Global models are in pretty good alignment
with both timing and location of the front as it pushes through
Saturday night, stalling it near south Georgia Sunday morning.
Front will be the focus of some overnight storms and rain given
tropical airmass, and as it stalls we could see some isentropic
overrunning that allows for some elevated rain or even convection
across the CWA on Sunday, though less certain on the details of
how this may play out.

Relatively drier and even cooler airmass will be in place behind the
front bringing some much needed relief for a few days from the
oppressive tropical airmass that has been in place. Still, it's
summer in the south, and it won't take long for enough heating to
occur to allow for some diurnal chances Monday and Tuesday. Some
divergence in the models begin to take place after this, though
Wednesday looks like another diurnal day of convection across the
global guidance. Details of a western ridge and eastern trough
will need to be worked out to determine how the rest of the week
will play out.

Lusk

&&

.AVIATION...
18Z Update...
VFR conditions to continue through the period. Isolated to
scattered SHRA/TSRA has initiated across the area and will likely
continue well into the evening with such an unstable airmass in
place. A TEMPO for TSRA and VRB gusts for ATL is valid 19-23Z,
with VCSH through 4Z to attempt to capture lingering convection.
Winds will be primarily from the W/NW at less than 10 kts through
the TAF period and nearly calm overnight. Potential for MVFR cigs
and patchy MVFR vsbys in the morning depending on where axis of
heavy rain falls. SHRA/TSRA chances to pick back up once again
around 17-18Z tomorrow.

//ATL Confidence...18Z Update...
Medium confidence potential morning MVFR cigs/vsbys.
High confidence all other elements.

96

&&

.PRELIMINARY POINT TEMPS/POPS...
Athens          97  75  95  75 /  50  40  60  40
Atlanta         95  75  93  76 /  50  40  60  40
Blairsville     90  69  90  69 /  60  30  60  40
Cartersville    95  73  94  74 /  60  40  60  40
Columbus        97  78  94  76 /  50  30  60  30
Gainesville     94  74  93  75 /  60  40  60  40
Macon           98  76  95  75 /  50  30  60  40
Rome            96  74  96  75 /  60  40  60  40
Peachtree City  96  74  93  73 /  50  30  60  40
Vidalia         97  77  94  76 /  50  30  60  30

&&

.FFC WATCHES/WARNINGS/ADVISORIES...
Heat Advisory until 7 PM EDT this evening for the following
zones: Baldwin...Banks...Barrow...Bartow...Bibb...Bleckley...
Butts...Carroll...Catoosa...Chattahoochee...Chattooga...
Cherokee...Clarke...Clayton...Cobb...Coweta...Crawford...Crisp...
Dade...DeKalb...Dodge...Dooly...Douglas...Emanuel...Fayette...
Floyd...Forsyth...Glascock...Gordon...Greene...Gwinnett...Hall...
Hancock...Haralson...Harris...Heard...Henry...Houston...
Jackson...Jasper...Jefferson...Johnson...Jones...Lamar...
Laurens...Macon...Madison...Marion...Meriwether...Monroe...
Montgomery...Morgan...Murray...Muscogee...Newton...North
Fulton...Oconee...Oglethorpe...Paulding...Peach...Pike...Polk...
Pulaski...Putnam...Rockdale...Schley...South Fulton...Spalding...
Stewart...Sumter...Talbot...Taliaferro...Taylor...Telfair...
Toombs...Treutlen...Troup...Twiggs...Upson...Walker...Walton...
Warren...Washington...Webster...Wheeler...Whitfield...Wilcox...
Wilkes...Wilkinson.

&&

SHORT TERM...Thiem
LONG TERM....Lusk
AVIATION...96

Hazardous Weather Outlook
National Weather Service Peachtree City GA
1049 AM EDT Thu Jul 7 2022

GAZ001>009-011>016-019>025-027-030>039-041>062-066>076-078>086-
089>098-102>113-081500-
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-
1049 AM EDT Thu Jul 7 2022

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

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

Scattered thunderstorms will be possible today into tonight
across north and central Georgia. Some strong to isolated severe
storms are possible with the primary hazards of damaging wind
gusts, locally heavy rainfall that could lead to flash flooding
and frequent lightning.

A heat advisory is in effect for all but the mountainous areas of
north and central Georgia. Heat indices between 105 and 109 will
be possible. Please use caution when exercising or working
outdoors and take frequent breaks.

.DAYS TWO THROUGH SEVEN...Friday through Wednesday...

Additional Heat Advisories could be warranted across portions of
the area Friday and Saturday.

Scattered thunderstorms will be possible each afternoon and
evening. Some storms could become strong to severe with damaging
winds, locally heavy rainfall, and frequent lightning.

.SPOTTER INFORMATION STATEMENT...

Spotter activation will not be needed through tonight.

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE PEACHTREE CITY GA
1247 PM EDT THU JUL 07 2022

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

1120 PM     TSTM WND DMG     4 NNW HARMONY           33.51N  83.39W
07/06/2022                   MORGAN             GA   EMERGENCY MNGR

            ONE TREE DOWN AT ENTERPRISE AND SEVEN ISLANDS ROAD.

&&

EVENT NUMBER FFC2200779

NLIST

Special Weather Statement
National Weather Service Peachtree City GA
1258 PM EDT Thu Jul 7 2022

GAZ072-082-083-071730-
Bibb GA-Jones GA-Twiggs GA-
1258 PM EDT Thu Jul 7 2022

...A strong thunderstorm will impact portions of central Bibb,
northwestern Twiggs and southeastern Jones Counties through 130 PM
EDT...

At 1257 PM EDT, a strong thunderstorm was centered near the north
side of Macon, moving southeast at 5 mph.

HAZARD...Up to 40 mph wind, frequent cloud to ground lightning and
         heavy rain.

SOURCE...Radar indicated.

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.

Locations impacted include...
Macon, Payne, Payne City, Cross Keys, Wesleyan, Dry Branch, Postell,
Arkwright, Mountain Springs, Griswoldville, Franklinton and Clinton.

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 3291 8377 3302 8359 3291 8344 3278 8350
      3277 8372
TIME...MOT...LOC 1657Z 325DEG 4KT 3291 8366

MAX HAIL SIZE...0.00 IN
MAX WIND GUST...40 MPH

Special Weather Statement
National Weather Service Peachtree City GA
105 PM EDT Thu Jul 7 2022

GAZ097-071730-
Laurens GA-
105 PM EDT Thu Jul 7 2022

...A strong thunderstorm will impact portions of northeastern Laurens
County through 130 PM EDT...

At 105 PM EDT, a strong thunderstorm was centered near Dublin. This
storm was nearly stationary.

HAZARD...Up to 40 mph wind, frequent cloud to ground lightning and
         heavy rain.

SOURCE...Radar indicated.

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.

Locations impacted include...
Dublin, East Dublin, Brewton and Minter.

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 3240 8274 3242 8293 3255 8298 3263 8283
      3255 8267 3254 8267
TIME...MOT...LOC 1705Z 325DEG 4KT 3253 8286

MAX HAIL SIZE...0.00 IN
MAX WIND GUST...40 MPH

Special Weather Statement
National Weather Service Peachtree City GA
205 PM EDT Thu Jul 7 2022

GAZ098-112-071830-
Treutlen GA-Montgomery GA-
205 PM EDT Thu Jul 7 2022

...A strong thunderstorm will impact portions of southeastern
Treutlen and northeastern Montgomery Counties through 230 PM EDT...

At 205 PM EDT, a strong thunderstorm was centered near Zaidee, or
just east of Soperton, moving southeast at 15 mph.

HAZARD...Up to 40 mph wind, frequent cloud to ground lightning and
         heavy rain.

SOURCE...Radar indicated.

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.

Locations impacted include...
Soperton, Higgston, Tarrytown, Zaidee and Kibbee.

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 3237 8241 3235 8241 3226 8244 3222 8246
      3224 8256 3234 8264 3244 8251 3241 8239
TIME...MOT...LOC 1805Z 305DEG 12KT 3237 8253

MAX HAIL SIZE...0.00 IN
MAX WIND GUST...40 MPH

Special Weather Statement
National Weather Service Peachtree City GA
216 PM EDT Thu Jul 7 2022

GAZ001-002-071900-
Walker GA-Dade GA-
216 PM EDT Thu Jul 7 2022

...A strong thunderstorm will impact portions of north central Walker
and northern Dade Counties through 300 PM EDT...

At 216 PM EDT, a strong thunderstorm was near Haletown (guild), or
near Jasper, moving southeast at 20 mph.

HAZARD...40 to 50 mph wind, up to penny sized hail and frequent
         cloud to ground lightning.

SOURCE...Radar indicated.

IMPACT...Expect minor damage to tree limbs and blowing around of
         light, unsecured objects.

Locations impacted include...
Trenton, Lookout Mountain, Chattanooga  Valley, New England,
Morganville, Hooker, Cole City, Wildwood and Fairview.

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 3498 8560 3498 8527 3497 8527 3491 8533
      3486 8549 3492 8559
TIME...MOT...LOC 1816Z 313DEG 18KT 3507 8556

MAX HAIL SIZE...0.75 IN
MAX WIND GUST...50 MPH

Special Weather Statement
National Weather Service Peachtree City GA
218 PM EDT Thu Jul 7 2022

GAZ002-011-012-019-071845-
Chattooga GA-Walker GA-Gordon GA-Floyd GA-
218 PM EDT Thu Jul 7 2022

...A strong thunderstorm will impact portions of northeastern Floyd,
southeastern Walker, western Gordon and northeastern Chattooga
Counties through 245 PM EDT...

At 218 PM EDT, a strong thunderstorm was over Everett Springs, or 10
miles west of Calhoun, moving southeast at 15 mph.

HAZARD...40 to 50 mph wind, pea sized hail and frequent cloud to
         ground lightning.

SOURCE...Radar indicated.

IMPACT...Expect minor damage to tree limbs and blowing around of
         light, unsecured objects.

Locations impacted include...
Calhoun, Summerville, Oostanaula, Subligna, Sugar Valley, Tidings,
Everett Springs, Lake Marvin and James H. Floyd State Park.

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 3456 8524 3464 8511 3458 8500 3450 8495
      3440 8505 3439 8523 3442 8534 3448 8536
TIME...MOT...LOC 1818Z 306DEG 15KT 3451 8513

MAX HAIL SIZE...0.25 IN
MAX WIND GUST...50 MPH