Special Weather Statement, NWS Columbia, SC

Area Forecast Discussion
National Weather Service Columbia SC
241 PM EDT Tue Jul 20 2021

.SYNOPSIS...
A nearly stationary front, and copious atmospheric moisture,
will continue to provide high chances of showers and
thunderstorms again Today. Upper level troughing will remain
persistent over the eastern US through much of the weekend.
This pattern supports At least a chance of showers and
thunderstorms each day.

&&

.NEAR TERM /THROUGH TONIGHT/...
The boundary has lowered just south of Columbia with anonymously
high, above 2 inch pwats in the CSRA and southern Midlands.
This area has already seen some high precip over the past three
days and is the main focus for any localized flooding over the
course of the afternoon and evening. Some heavy showers are
moving through our southern counties, slowly traveling along the
boundary. Urban flooding possible within some of these heavier,
slower moving cells. Convection will increase through the
afternoon with isolated to scattered thunderstorms in addition
to widespread showers along and south of I-26. Deeper
convergence is mainly along the CSRA and would likely see more
thunderstorm activity. Rain will begin to diminish for a time
after 00z. Another shortwave will pass through the area late
this evening initiating more showers and possible thunderstorms.
Convection will become isolated a few hours after midnight.
Extensive cloud coverage will keep temperatures similar to
this morning around 70.

&&

.SHORT TERM /WEDNESDAY THROUGH WEDNESDAY NIGHT/...
An upper level trough will be located over the US East Coast. A
stalled frontal boundary will be located near or over the area.
PWAT values will be near or over 2 inches across the southern FA
with sharply decreasing values to the north. Lift along the
front and abundant moisture will allow showers and thunderstorms
to develop during the late morning and afternoon. Coverage
should be highest along and south of the front. Heavy rain and
flash flooding will be possible tomorrow. Convergence along the
front is weak but a west-east oriented boundary and parallel
mid level flow would suggest favorable conditions for training
convection. Since moisture advection will be weak, widespread
heavy rain appears unlikely but isolated flash flooding could
be possible where showers/storms train. Models show some drier
air pushing in from the north during the afternoon so PoPs will
be lowest in the northern FA.

Overcast skies and showers should keep temperatures low
tomorrow. Highs may only be in the mid 80s. Lows will be in the
low 70s for most areas.

&&

.LONG TERM /THURSDAY THROUGH MONDAY/...
Little change to the long term forecast. Global ensembles
continue to keep a persistent trough over the eastern US
through much of the weekend. Upper level winds will be out of
the NW for our region, and PW values will be near climatological
normals. This pattern supports at least a chance of showers and
thunderstorms each day late this week and into the weekend.
Temperatures should be near or slightly below normal. By late in
the forecast period, the upper trough is expected to push out
of the region with upper heights building over the Southeast.
This would bring a more typical summerlike pattern for the
remainder of the long term with mainly scattered diurnal
convection and near or above normal temps.

&&

.AVIATION /18Z TUESDAY THROUGH SUNDAY/...
Short periods of VFR outside of rain and thunderstorms, but
mainly MVFR/IFR.

MVFR outside of rain and storms with brief VFR periods possible
through the afternoon. Better probabilities of thunder at
OGB/DNL/AGS. Visibility restrictions in heavy storms.
Overnight conditions will be dependent on location of rainfall
this evening. Ceilings and visibilities will lower again tonight
with excessive moisture still present. Improvement to VFR
tomorrow morning. Winds will calm overnight and become
southerly around 5kt by midmorning.

EXTENDED AVIATION OUTLOOK...Restrictions possible
each day within thunderstorms and early morning stratus/fog.
Chances of restrictions may decrease later this week.

&&

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

&&

SYNOPSIS...
NEAR TERM...
SHORT TERM...
LONG TERM...
AVIATION...

Hazardous Weather Outlook
National Weather Service Columbia SC
358 AM EDT Tue Jul 20 2021

GAZ040-063>065-077-SCZ016-018-020>022-025>031-035-037-038-041-115-
116-135>137-210800-
Lincoln-McDuffie-Columbia-Richmond-Burke-Chesterfield-McCormick-
Newberry-Fairfield-Kershaw-Edgefield-Saluda-Lexington-Richland-Lee-
Aiken-Sumter-Barnwell-Calhoun-Clarendon-Bamberg-Northern Lancaster-
Southern Lancaster-Northwestern Orangeburg-Central Orangeburg-
Southeastern Orangeburg-
358 AM EDT Tue Jul 20 2021

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

.DAY ONE...Today and tonight.

Locally heavy rain possible.

.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.

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE COLUMBIA SC
1040 AM EDT TUE JUL 20 2021

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

0830 AM     FLOOD            10 S MONETTA            33.71N 81.60W
07/20/2021                   AIKEN              SC   EMERGENCY MNGR

            EMERGENCY MANAGER REPORTED THE ROADWAY
            FLOODED AT THE INTERSECTION OF KEDRON CHURCH
            ROAD AND CUMBEE TRAIL ROAD.

&&

LCV

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE COLUMBIA SC
1041 AM EDT TUE JUL 20 2021

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

0830 AM     FLOOD            4 S MONETTA             33.79N 81.61W
07/20/2021                   AIKEN              SC   EMERGENCY MNGR

            EMERGENCY MANAGER REPORTED ONGOING FLOODING
            OF THE ROADWAY ALONG OLD SHOALS ROAD NEAR
            THE BRIDGE CROSSING MCTIER CREEK. THIS IS
            JUST NORTH OF THE INTERSECTION OF OLD SHOALS
            ROAD AND MT. PLEASANT ROAD. ROADWAY
            CURRENTLY CLOSED.

&&

LCV

Special Weather Statement
National Weather Service Columbia SC
344 PM EDT Tue Jul 20 2021

GAZ064-065-077-SCZ025-030-202045-
Burke GA-Richmond GA-Columbia GA-Aiken SC-Edgefield SC-
344 PM EDT Tue Jul 20 2021

...Strong Thunderstorms Will Impact Portions of northwestern Burke...
Richmond...southeastern Columbia...west central Aiken and south
central Edgefield Counties Until 445 PM EDT....

At 342 PM EDT...National Weather Service doppler radar indicated
strong thunderstorms along a line extending from 7 miles north of
Belvedere to 6 miles southwest of Wrens, moving east at 15 mph.

  HAZARD...gusty winds 40 to 50 mph and localized minor flooding.

  IMPACT...expect minor damage to tree limbs and blowing around of
           light, unsecured objects. Localized minor flooding of low
           lying and poor drainage areas is also possible.

Some locations in the path of these storms include...
Aiken, North Augusta, Grovetown, Evans, Martinez, Fort Gordon,
Augusta, Clearwater, Belvedere, Hephzibah, Glendale, Gough, South
Augusta, Midtown, Summerville, Augusta Mall, Daniel Field, Augusta
Regional Airport, Village Plaza Shopping Center and Augusta National
Golf Club.

Heavy rainfall is occurring with these storms, and may cause
localized flooding. Visibilities will be reduced to 1/2 miles or
less in the heavy rain as well. Motorists are urged to slow down and
drive at safe speeds. Do not drive your vehicle through flooded
roadways.

This includes the following highways...
 Interstate 20 in Georgia between mile markers 193 and 201.
 Interstate 20 in South Carolina between mile markers 0 and 23.
 Interstate 520 in Georgia between mile markers 1 and 15.
 Interstate 520 in South Carolina between mile markers 16 and 23.

LAT...LON 3323 8223 3326 8225 3327 8229 3330 8232
      3368 8195 3369 8164 3309 8214 3308 8229
TIME...MOT...LOC 1942Z 256DEG 15KT 3364 8194 3312 8243

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