Hail and Damaging Winds in Georgia, June 22, 2019

Area Forecast Discussion
National Weather Service Charleston SC
440 AM EDT Sat Jun 22 2019

.SYNOPSIS...
A stationary front will remain across the region through this
weekend. High pressure is expected to build over the Southeast
U.S. early next week. A cold front is forecast to slowly move
across the Coastal Plain Wednesday into Thursday.

&&

.NEAR TERM /THROUGH TONIGHT/...
Pre-dawn: Overnight, a potent MCS produced a large swath of severe
weather across the Tennessee Valley and mountains. This convective
complex was still an upstream concern for our forecast area
prior to daybreak as it shifts from the SC midlands to the coast.
We introduced POPs for showers and tstms into zones north of
I-16 in GA, east to our SC zones over the next few hours. The
risk of severe weather is a bit uncertain as this complex still
remains intact. We may end up with a few Severe Tstm Warnings
but it appears the strongest wind momentum will brush the parts
of the Charleston Quad-County area. The momentum of the MCS
should continue to drift a boundary into our region with stronger
winds possible in stronger convective cells which remain anchored
in 25-30 kt of effective shear early this morning.

Today: The forecast remains extremely complex with lower than
usual confidence in this first period. Remnants of the overnight
MCS are expected to push offshore of the eastern Carolinas
prior to mid morning but not before producing scattered
convection and debris cloudiness in some form of mid/high clouds
to start the day. The ECMWF was most robust with morning QPF
across our region, and it's latest 12 hr progression of
convective rains may be best of the global models. There is good
consensus that by late morning into early afternoon, clouds in
the wake of the MCS will dissipate as west flow resides in the
boundary layer and keeps the sea breeze closer to the coast. The
complexity of the morning mesoscale and presence of more clouds
early on puts an uncertainty for heat advisories which were in
effect across parts of the forecast area. We maintained the
advisories but it will likely be marginal this afternoon give
some of the very latest guidance.

Severe Convection Potential: Overall, models continue to show
fairly extreme instability parameters developing ahead a mid
level short wave in northwest flow aloft. We expect an uptick
in convection after mid afternoon as organized convection is
expected to evolve over GA and SC. The intensity and scale of
severe weather will depend on many factors, including boundaries
left over from this morning's storms and differential heating
just to name a couple features. The potential for significant
cold pooling will be there if diurnal instability is realized
and this is a concern for more extensive wind damage potential.
At this point, the SPC slight risk across the region is a good
call given the myriad of uncertainties. Steep low and mid level
lapse rates are a concern to see in the model field coincident
with each other, suggestive of both a large hail and damaging
wind threat. Timing remains another issue and will continue to
be addressed through the day.

&&

.SHORT TERM /SUNDAY THROUGH TUESDAY/...
The mid-levels will consist of ridging building over the Southeast
Sunday through Monday night, followed by the ridge axis moving
offshore on Tuesday. Several short waves within the overall flow are
expected to pass overhead or nearby during the short term, enhancing
the risk for convection at various times. At the surface, a
stationary front will be over or just north of the Charleston Tri-
County Sunday morning. This front will lift northward Sunday night
while inland troughing develops. The trough is expected to prevail
through Monday. A cold front is expected to approach from the
northwest on Tuesday, possibly making it to our area late in the
day. Moisture and instability will be in place each afternoon, which
is no surprise given it's now officially summer. The question will
be the thunderstorm risk every day. All the models have differing
opinions, forcing us to go with a mix and match strategy each day.
This equates to chance POPs Sunday afternoon and slight chance POPs
Monday and Tuesday afternoon. The forecast for each of these days
will need to get better defined as it goes to the near term. Some
severe thunderstorms containing damaging winds are possible each
afternoon. High temperatures should be a few degrees above normal,
mainly Monday and Tuesday. Additionally, heat index values around
105 F each afternoon (especially in the coastal corridor) could
prompt more Heat Advisories.

&&

.LONG TERM /TUESDAY NIGHT THROUGH FRIDAY/...
A stationary front or weak inland trough will prevail across the
Southeast. This will bring our area the typical afternoon/evening
showers and thunderstorms.

&&

.AVIATION /08Z SATURDAY THROUGH WEDNESDAY/...
We will be watching a convective system move out of the mountains
overnight with potential that showers and tstms hold together,
reaching the coast around daybreak with some strong wind gusts
possible. We have low confidence given latest model output and
mesoscale trends. Both CHS and SAV will likely see at least 1
round of tstms late today. Strong instability is expected and
the storms could be strong to severe. Otherwise, little change
with VFR conditions prevailing.

Extended Aviation Outlook: Brief flight restrictions are possible in
afternoon/evening showers/thunderstorms.

&&

.MARINE...
The main issue for the forecast today will be the potential for
strong to severe tstms moving off the coast later today and this
evening. There is also a risk for strong tstms along the SC
coast nearing daybreak as a weakening MCS moves into the area.
Otherwise, a weak boundary will likely stagnate somewhere along
the upper SC coast and winds could go light and variable over
Charleston waters at some point outside convection tonight.
Through tonight winds will be mainly 15 kt or less and seas 2-3
ft.

Extended Marine: A stationary front will remain across the region
through this weekend. High pressure is expected to build over the
Southeast U.S. early next week. A cold front is forecast to slowly
move across the Coastal Plain Wednesday into Thursday. Winds/seas
are expected to remain below Small Craft Advisory criteria.

&&

.CHS WATCHES/WARNINGS/ADVISORIES...
GA...Heat Advisory from 10 AM this morning to 6 PM EDT this evening
     for GAZ099>101-114>119-137>141.
SC...Heat Advisory from 10 AM this morning to 6 PM EDT this evening
     for SCZ042>044-047>052.
MARINE...None.

&&

NEAR TERM...
SHORT TERM...
LONG TERM...
AVIATION...
MARINE...

Hazardous Weather Outlook
National Weather Service Charleston SC
439 AM EDT Sat Jun 22 2019

GAZ099>101-114>119-137>141-SCZ042>044-047>052-230845-
Candler-Bulloch-Effingham-Tattnall-Evans-Inland Bryan-Coastal Bryan-
Inland Chatham-Coastal Chatham-Long-Inland Liberty-Coastal Liberty-
Inland McIntosh-Coastal McIntosh-Hampton-Inland Colleton-Dorchester-
Inland Jasper-Beaufort-Coastal Colleton-Charleston-Coastal Jasper-
Tidal Berkeley-
439 AM EDT Sat Jun 22 2019

...HEAT ADVISORY IN EFFECT FROM 10 AM THIS MORNING TO 6 PM EDT THIS
EVENING...

This Hazardous Weather Outlook is for southeast Georgia and
southeast South Carolina.

.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.

   Heat Advisory.

Severe Thunderstorms: A squall line will move through Southeast South
Carolina and Southeast Georgia this morning. Another line of
thunderstorms is expected this afternoon or evening. Severe
thunderstorms with damaging winds are expected.

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

Excessive Heat: The combination of hot temperatures and moderate
humidity could produce afternoon heat index values around 105 degrees
across Southeast South Carolina and Southeast Georgia Sunday, Monday,
and Tuesday. Heat Advisories may be needed.

.SPOTTER INFORMATION STATEMENT...

Spotter assistance is not anticipated at this time.

GAZ087-088-SCZ040-045-230845-
Jenkins-Screven-Allendale-Inland Berkeley-
439 AM EDT Sat Jun 22 2019

This Hazardous Weather Outlook is for southeast Georgia and
southeast South Carolina.

.DAY ONE...Today and tonight.

Severe Thunderstorms: A squall line will move through Southeast South
Carolina and Southeast Georgia this morning. Another line of
thunderstorms is expected this afternoon or evening. Severe
thunderstorms with damaging winds are expected.

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

Excessive Heat: The combination of hot temperatures and moderate
humidity could produce afternoon heat index values around 105 degrees
across Southeast South Carolina and Southeast Georgia Sunday, Monday,
and Tuesday. Heat Advisories may be needed.

.SPOTTER INFORMATION STATEMENT...

Spotter assistance is not anticipated at this time.

AMZ330-350-352-354-374-230845-
Charleston Harbor-
Waters from South Santee River to Edisto Beach SC out 20 NM-
Waters from Edisto Beach SC to Savannah GA out 20 NM-
Waters from Savannah GA to Altamaha Sound GA out 20 NM, including
Grays Reef National Marine Sanctuary-
Waters from Savannah GA to Altamaha Sound GA from 20 to 60 NM-
439 AM EDT Sat Jun 22 2019

This Hazardous Weather Outlook is for Atlantic coastal waters.

.DAY ONE...Today and tonight.

Severe Thunderstorms: A squall line will move through Southeast South
Carolina and Southeast Georgia this morning. Another line of
thunderstorms is expected this afternoon or evening. Severe
thunderstorms with winds exceeding 34 kt are expected.

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

There is a low probability for widespread hazardous weather.

.SPOTTER INFORMATION STATEMENT...

Spotter assistance is not anticipated at this time.

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE CHARLESTON SC
554 AM EDT SAT JUN 22 2019

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

0549 AM     HAIL             3 SSW BONNEAU           33.26N  79.98W
06/22/2019  E0.88 INCH       BERKELEY           SC   PUBLIC

            A MEMBER OF THE PUBLIC REPORTED NICKEL-SIZE HAIL AND
            ESTIMATED WINDS 60 MPH OR GREATER.

&&

EVENT NUMBER CHS1900642

BRM