Severe Thunderstorm Warning 117, NWS Columbia, SC

Area Forecast Discussion
National Weather Service Columbia SC
239 PM EDT Tue Jun 23 2020

.SYNOPSIS...
The chance of showers and thunderstorms will continue through
mid to late week as moisture and the next frontal boundary move
into the region. Temperatures will be near or above normal.

&&

.NEAR TERM /THROUGH TONIGHT/...
An upper trough over the Great Lakes region will gradually move
eastward while a shortwave rotates through the base of the
trough through the forecast area late this afternoon. Deep
moisture is in place across the area with pwat values around 1.8
to 2.0 inches. The moist airmass combined with heating and the
presence of a lee- side trough will allow isolated to scattered
showers and thunderstorms to develop early this afternoon. Radar
shows the convection associated with the trough as of 1830Z
extending through the western Carolinas into central GA. This
broken line is expected to continue to move eastward and into
the forecast area by late afternoon. The forecast area is
outlooked in a marginal risk for severe weather by SPC, but the
overall severe threat appears low. Damaging winds are the
primary severe threat, although DCAPE is currently unimpressive
at 400 to 500 J/kg. Instability appears weak and shear is weak.
Convective activity and wind gusts should diminish during the
evening as the shortwave moves out and the conditional
instability is lost. Overnight lows around 70.

&&

.SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
Wednesday morning, one short wave will have moved offshore, but a
streamer of vorticity will hang back across the southern half of the
area as another shortwave follows closely on its heels within the
eastern North America large scale trough. At the surface, a weak
front will sag into South Carolina from the north, but will likely
stall across the northern parts of the FA, keeping most of us in a
warm and humid airmass, which will become moderately unstable by
afternoon. As the aforementioned shortwave approaches, more showers
and thunderstorms are expected to develop, with the best chances
along and south of the weak front.

By the late afternoon and evening, winds in the 850-500 mb layer
will increase somewhat, so its possible the convection would form
into multicell clusters with some organization. Were that to happen,
a few severe storms would be possible.

Wednesday night, lingering convection should be done by midnight as
the upper energy moves away and diurnal effects diminish the
instability.

On Thursday, the deepest moisture will pull away from the
southeastern states as heights slowly build aloft. The surface front
will have moved out by then as well, so the chances of convection
should drop down to the lower end of the chance category. The air
mass will be a touch cooler, and winds will pick up a little, so
conditions will not be overly oppressive.

&&

.LONG TERM /FRIDAY THROUGH TUESDAY/...
Heights will continue to build aloft Friday into the weekend as
the low level bermuda high builds westward across northern
Florida and the northern Gulf of Mexico. Low level temps will be
on the rise as well, with highs expected to be at least mid 90s
in many places. Chances of rain will be lower due to large
scale subsidence, but the near surface thermal trof could still
be the focus for a few scattered thunderstorms by late each day.

The one fly in the ointment for the weekend is the eventual
evolution of the SAL dust over the area. Mid layer trajectories
would suggest that some of that may work its way into the FA,
especially by Sunday. Were this to happen, it could potentially
knock down max temps by a couple of degrees and make the chances of
rain even lower by enhancing the expected low level cap. It's too
early in the forecast cycle to get too cute, however, as the amount
and timing is still uncertain.

Early next week, a cutoff low is forecast to develop by the global
models over eastern Canada and New England. However, there is some
question as to how far south the influence of the cutoff will get.
If it becomes deep enough, it could drive a cold front through the
area from the north. While this is possible, it could also struggle
to get into South Carolina and Georgia, given the region a hot and
dry pattern. I'm going with a near seasonable forecast for now.
Also, some effects from the SAL may still be in play.

&&

.AVIATION /19Z TUESDAY THROUGH SUNDAY/...
VFR conditions expected outside of afternoon/evening convection.

Isolated to scattered thunderstorms should develop in the early
afternoon due to the warm, moist airmass. Radar showing a line
of mainly showers extending from western NC through central GA
which is expected to track towards region later this afternoon
with convective coverage increasing. Most of the convection will
diminish with loss of heating this evening. Winds will continue
out of the southwest through the afternoon at around 12 knots
gusting to 18 to 20 knots. Higher gusts possible in
thunderstorms. Fog potential is low tonight due to a 20 know low
level jet and clouds.

EXTENDED AVIATION OUTLOOK...CIG/VSBY conditions through the end of the week
will be mainly impacted by scattered afternoon/evening convection.
Some dust may make it into the area over the weekend, but at the
current time I am not expecting anything but VFR vsbys from the
SAL.

&&

.CAE WATCHES/WARNINGS/ADVISORIES...
GA...None.
SC...None.

&&

Hazardous Weather Outlook
National Weather Service Columbia SC
322 AM EDT Tue Jun 23 2020

GAZ040-063>065-077-SCZ016-018-020>022-025>031-035>038-041-115-116-
240730-
Lincoln-McDuffie-Columbia-Richmond-Burke-Chesterfield-McCormick-
Newberry-Fairfield-Kershaw-Edgefield-Saluda-Lexington-Richland-Lee-
Aiken-Sumter-Barnwell-Orangeburg-Calhoun-Clarendon-Bamberg-
Northern Lancaster-Southern Lancaster-
322 AM EDT Tue Jun 23 2020

This Hazardous Weather Outlook is for the Midlands of South Carolina
and the Central Savannah River area of Georgia.

.DAY ONE...Today and tonight.

The probability for widespread hazardous weather is low.

.DAYS TWO THROUGH SEVEN...Wednesday through Monday.

The probability for widespread hazardous weather is low.

.SPOTTER INFORMATION STATEMENT...

Spotter activation is not expected at this time.

Special Weather Statement
National Weather Service Columbia SC
456 PM EDT Tue Jun 23 2020

SCZ021-022-027-028-116-232200-
Fairfield SC-Lexington SC-Southern Lancaster SC-Richland SC-
Kershaw SC-
456 PM EDT Tue Jun 23 2020

...Strong Thunderstorms Will Impact Portions of eastern Fairfield...
central Lexington...Southern Lancaster...Richland and Kershaw
Counties Until 600 PM EDT....

...Boaters on Lake Wateree Should Seek Safe Harbor...

At 455 PM EDT...National Weather Service doppler radar indicated
strong thunderstorms along a line extending from near Fort Lawn to 9
miles southwest of Red Bank, moving east at 30 mph.

  HAZARD...strong winds 45 to 55 mph.

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

Some locations in the path of these storms include...
Columbia, Lexington, West Columbia, Cayce, Irmo, Forest Acres,
Lancaster, Camden, Winnsboro, Springdale, Dentsville, Oak Grove, Lake
Wateree Dam, St. Andrews, McEntire Air Base, Highway 6 at Lake Murray
Dam, Red Bank, South Congaree, Pine Ridge and Kershaw.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Boaters on Lake Wateree should move to shore and seek shelter.
Strong, erratic wind gusts and lightning are possible. If you can
hear thunder, you are close enough to be struck by lightning.

&&

This includes the following highways...
 Interstate 126 between mile markers 0 and 3.
 Interstate 20 in South Carolina between mile markers 48 and 104.
 Interstate 26 between mile markers 98 and 120.
 Interstate 77 between mile markers 0 and 51.

LAT...LON 3459 8038 3444 8033 3429 8041 3428 8044
      3417 8048 3409 8064 3404 8060 3400 8065
      3397 8062 3390 8062 3378 8069 3378 8083
      3388 8100 3387 8104 3379 8105 3380 8139
      3455 8101 3455 8087 3481 8088 3481 8056
TIME...MOT...LOC 2055Z 274DEG 28KT 3474 8090 3384 8136

Special Weather Statement
National Weather Service Columbia SC
458 PM EDT Tue Jun 23 2020

SCZ030-035>037-041-232200-
Orangeburg SC-Barnwell SC-Aiken SC-Calhoun SC-Bamberg SC-
458 PM EDT Tue Jun 23 2020

...Strong Thunderstorms Will Impact Portions of northwestern
Orangeburg...northeastern Barnwell...central Aiken...western Calhoun
and northwestern Bamberg Counties Until 600 PM EDT....

At 458 PM EDT...National Weather Service doppler radar indicated a
strong thunderstorm near New Ellenton, or near Aiken Mall, moving
east at 30 mph.

  HAZARD...strong winds 45 to 55 mph.

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

Some locations in the path of this storm include...
Aiken, Denmark, Aiken Mall, Williston, Blackville, New Ellenton,
Citizens Park, Barnwell State Park, Aiken State Park, North,
Springfield, Hilda, Salley, Neeses, Norway, Perry, Elko, Woodford,
Livingston and Windsor.

LAT...LON 3336 8173 3355 8171 3367 8122 3366 8121
      3366 8118 3370 8109 3371 8104 3323 8106
TIME...MOT...LOC 2058Z 265DEG 27KT 3346 8163

Special Weather Statement
National Weather Service Columbia SC
529 PM EDT Tue Jun 23 2020

GAZ064-065-077-232215-
Burke GA-Richmond GA-Columbia GA-
529 PM EDT Tue Jun 23 2020

...Strong Thunderstorms Will Impact Portions of northwestern Burke...
Richmond and south central Columbia Counties Until 615 PM EDT....

At 529 PM EDT...National Weather Service doppler radar indicated a
strong thunderstorm near Grovetown, moving southeast at 20 mph.

  HAZARD...strong winds 45 to 55 mph and pea sized hail.

  IMPACT...expect minor damage to tree limbs and blowing around of
           light, unsecured objects. Minor hail damage to plants,
           trees and crops is possible. Damage to windshields is
           unlikely.

Some locations in the path of this storm include...
Grovetown, Fort Gordon, Hephzibah, Harlem, McBean, South Augusta,
Blythe, Keysville, Leitner Lake Conference Center, Liberty Park
Community Center, Bath-Edie, Pea Patch Aerodrome, Bennock Mill,
Ellwood and Diamond Lakes Regional Park.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

This storm may intensify. Monitor NOAA Weather Radio, local radio and
television stations for additional information and possible warnings
from the National Weather Service.

&&

This includes Interstate 20 in Georgia between mile markers 187 and
189.

LAT...LON 3335 8230 3339 8232 3350 8224 3330 8186
      3329 8186 3326 8183 3311 8227 3313 8228
      3323 8223 3327 8226 3327 8229 3330 8231
      3331 8235
TIME...MOT...LOC 2129Z 304DEG 19KT 3338 8223

<!doctype html>
<html lang="en">
<head>
  <meta charset="utf-8">
  <meta name="viewport" content="width=device-width, initial-scale=1">
  <title>Service Notice</title>
  <link rel="stylesheet" href="index.css">
</head>
<body>
  <main class="wrap">
    <section class="card" role="status" aria-live="polite">
      <div class="status" id="status">Temporary Notice</div>
      <h1 id="headline">This service is currently unavailable.</h1>
      <p id="message1">
        The site you requested is temporarily down for maintenance or an unexpected outage.
      </p>
      <p id="message2">
        Please try again in a few minutes.
      </p>
      <p class="small" id="detail">
        If you are an administrator, restore upstream service and remove the redirect/fallback rule when normal operations resume.
      </p>
    </section>
  </main>
  <script src="index.js"></script>
</body>
</html>

<!doctype html>
<html lang="en">
<head>
  <meta charset="utf-8">
  <meta name="viewport" content="width=device-width, initial-scale=1">
  <title>Service Notice</title>
  <link rel="stylesheet" href="index.css">
</head>
<body>
  <main class="wrap">
    <section class="card" role="status" aria-live="polite">
      <div class="status" id="status">Temporary Notice</div>
      <h1 id="headline">This service is currently unavailable.</h1>
      <p id="message1">
        The site you requested is temporarily down for maintenance or an unexpected outage.
      </p>
      <p id="message2">
        Please try again in a few minutes.
      </p>
      <p class="small" id="detail">
        If you are an administrator, restore upstream service and remove the redirect/fallback rule when normal operations resume.
      </p>
    </section>
  </main>
  <script src="index.js"></script>
</body>
</html>

<!doctype html>
<html lang="en">
<head>
  <meta charset="utf-8">
  <meta name="viewport" content="width=device-width, initial-scale=1">
  <title>Service Notice</title>
  <link rel="stylesheet" href="index.css">
</head>
<body>
  <main class="wrap">
    <section class="card" role="status" aria-live="polite">
      <div class="status" id="status">Temporary Notice</div>
      <h1 id="headline">This service is currently unavailable.</h1>
      <p id="message1">
        The site you requested is temporarily down for maintenance or an unexpected outage.
      </p>
      <p id="message2">
        Please try again in a few minutes.
      </p>
      <p class="small" id="detail">
        If you are an administrator, restore upstream service and remove the redirect/fallback rule when normal operations resume.
      </p>
    </section>
  </main>
  <script src="index.js"></script>
</body>
</html>