Flash Flooding and Flood in South Carolina, September 2, 2016

Area Forecast Discussion
National Weather Service Columbia SC
841 AM EDT FRI SEP 2 2016

.SYNOPSIS...
A frontal boundary will remain stalled over the North Midlands
this morning. Hurricane Hermine will continue to lift
northeastward today move across South Carolina this afternoon then
exit the region by Saturday morning. Very heavy rainfall expected
across the region through tonight. Behind Hermine, drier and
cooler high pressure will build into the region for the weekend.

&&

.NEAR TERM /THROUGH TONIGHT/...
Hurricane Hermine made landfall earlier this morning along the Big
Bend area of the Florida coast and continues to slowly lift north
towards southern Georgia. The frontal boundary that pushed into
the area Thursday evening appears to have stalled and extends from
near Morehead City to Florence to near Atlanta. Regional radar
shows moderate rainfall occurring in the vicinity of the front
from southeast NC across northern/central SC into northern GA
while the northern edge of the rain shield associated with Hermine
pushes into southern SC.

Model forecasts and the official NHC forecast appear slightly
faster compared to earlier runs and expect the widespread rainfall
to begin to overspread the region from south to north over the
next few hours. Local mesonet around Columbia shows some stations
already have picked up 1-2 inches of rain associated with the
evening convection and stratiform rain near the frontal boundary
this morning. Flooding still appears the most significant risk for
our area with heavy rainfall expected as the storm moves into the
area later today with strong moisture convergence moving over the
area today possibly enhanced by dynamics associated with the right
entrance region of the upper jet. Storm total rainfall amounts
expected to be 4-6 inches in the eastern Midlands with locally
higher amounts and lower amounts in the 2-4 inch range across the
western Midlands. Expect some flooding issues to develop later
today and will continue the Flash Flood Watch that goes into
effect at 6am.

As Hermine lifts northward through the day the pressure gradient
will increase and we still expect significant winds to impact the
region. The strongest winds are expected closer to the center of
the storm in the eastern Midlands with wind speeds of 25 to 40
mph and much stronger gusts. Further away from the storm winds
will be strong as well and have decided to issue a wind advisory
for the remaining counties (northern and western Midlands and
upper CSRA) for today and tonight. As the ground becomes saturated
from the steady heavy rainfall later today, the increasing winds
will bring the potential for downed trees.  The more easterly
track of Hermine compared to previous days may limit the tornado
threat and confine it more along the coastal plain but the eastern
Midlands are still at risk as 0-1km SRH values exceed 200-400 m2s2
beginning later this morning through early evening.

Tonight Hermine is expected to lift northeast out of the area
during the 03z-06z time frame with some clearing skies late
tonight. Temperatures today will be limited by clouds and
precipitation and should struggle to get out of the 70s. Overnight
temperatures will be limited by wind and clouds but some cool
advection on the backside of the departing storm should allow
temperatures to fall into the mid and upper 60s.

&&

.SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
Fair weather is expected over the weekend in the wake of Hermine
with weak upper troughing remaining over the region and surface
ridging from the north. Cooler and drier air will circulate into
the region providing slightly below normal temperatures during
this period with highs in the mid 80s and lows in the 60s. No
rain expected over the weekend as precipitable water values drop
below 1.5 inches with a subsidence inversion also noted on
forecast soundings.

&&

.LONG TERM /MONDAY THROUGH THURSDAY/...
Fair weather is expected during this period as the region remains
between Hermine off the Mid-Atlantic/New England coast and a
building upper ridge to the west with generally northerly upper
level flow over the area. Precipitable water values will remain
quite low around or just over 1 inch and a mid level cap noted on
forecast soundings. Temperatures will gradually warm back above
normal this period with highs in the lower 90s and lows in the
upper 60s to lower 70s.

&&

.AVIATION /13Z FRIDAY THROUGH TUESDAY/...
Main precipitation shield associated with Tropical Cyclone
Hermine has shifted up into our forecast area (FA). At 12Z, the
center of TS Hermine was over S GA, and is forecast to move NE
across SE GA and S SC today into early tonight. Some weakening of
the circulation expected as center will remain over land. However,
widespread heavy rain, and associated CIG/VSBY restrictions, and
windy conditions expected at our terminals with the passage of the
cyclone. Conditions expected to improve behind the departing
cyclone this evening and early tonight, with gradually backing
winds and decreasing speeds.

EXTENDED AVIATION OUTLOOK...No impacts to aviation expected
Saturday through Tuesday.

&&

.HYDROLOGY...
Heavy rainfall associated with Hurricane Hermine will produce
significant rises on the area rivers. Total rainfall amounts from
2 to 6 inches with locally higher amounts possible. Although the
area rivers will rise significantly over the next several
days...only the North Fork of the Edisto River at Orangeburg is
expected to approach flood stage. The current forecast indicates
the river level rising to 7.8 feet with flood stage 8.0 feet. With
such a hot and relatively dry Summer at times combined with the
traditional draw down period of area reservoirs heading into the
Fall...the area reservoirs have storage available for the event.
The potential does exist for some flash flooding of local streams
and creeks.

&&

.CAE WATCHES/WARNINGS/ADVISORIES...
GA...Flash Flood Watch through late tonight FOR GAZ040-063>065-077.
     Wind Advisory until 2 AM EDT Saturday FOR GAZ040.
     High Wind Warning until 2 AM EDT Saturday FOR GAZ063>065-077.
SC...Flash Flood Watch through late tonight FOR SCZ015-016-018-
     020>022-025>031-035>038-041.
     Wind Advisory until 2 AM EDT Saturday FOR SCZ015-016-018-
     020>022-025-026.
     High Wind Warning until 2 AM EDT Saturday FOR SCZ027>031-
     035>038-041.

&&

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE COLUMBIA SC
505 AM EDT FRI SEP 2 2016

GAZ040-SCZ015-016-018-020>022-025-026-030915-
LINCOLN-LANCASTER-CHESTERFIELD-MCCORMICK-NEWBERRY-FAIRFIELD-KERSHAW-
EDGEFIELD-SALUDA-
505 AM EDT FRI SEP 2 2016

...FLASH FLOOD WATCH IN EFFECT THROUGH LATE TONIGHT...
...WIND ADVISORY IN EFFECT UNTIL 2 AM EDT SATURDAY...

THIS HAZARDOUS WEATHER OUTLOOK IS FOR THE MIDLANDS OF SOUTH CAROLINA
AND THE CENTRAL SAVANNAH RIVER AREA OF GEORGIA.

.DAY ONE...TODAY AND TONIGHT.

PLEASE LISTEN TO NOAA WEATHER RADIO OR GO TO WEATHER.GOV ON THE
INTERNET FOR MORE INFORMATION ABOUT THE FOLLOWING HAZARDS.

   FLASH FLOOD WATCH.
   WIND ADVISORY.

.DAYS TWO THROUGH SEVEN...SATURDAY THROUGH THURSDAY.

NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION WILL LIKELY BE NEEDED.

GAZ063>065-077-SCZ027>031-035>038-041-030915-
MCDUFFIE-COLUMBIA-RICHMOND-BURKE-LEXINGTON-RICHLAND-LEE-AIKEN-SUMTER-
BARNWELL-ORANGEBURG-CALHOUN-CLARENDON-BAMBERG-
505 AM EDT FRI SEP 2 2016

...FLASH FLOOD WATCH IN EFFECT THROUGH LATE TONIGHT...
...HIGH WIND WARNING IN EFFECT UNTIL 2 AM EDT SATURDAY...

THIS HAZARDOUS WEATHER OUTLOOK IS FOR THE MIDLANDS OF SOUTH CAROLINA
AND THE CENTRAL SAVANNAH RIVER AREA OF GEORGIA.

.DAY ONE...TODAY AND TONIGHT.

PLEASE LISTEN TO NOAA WEATHER RADIO OR GO TO WEATHER.GOV ON THE
INTERNET FOR MORE INFORMATION ABOUT THE FOLLOWING HAZARDS.

   FLASH FLOOD WATCH.
   HIGH WIND WARNING.

ISOLATED TORNADOES ARE ALSO POSSIBLE TODAY ACROSS THE SOUTHEASTERN
MIDLANDS AND LOWER CSRA.

.DAYS TWO THROUGH SEVEN...SATURDAY THROUGH THURSDAY.

NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION WILL LIKELY BE NEEDED.