Hail in Georgia, April 9, 2019

Area Forecast Discussion
National Weather Service Greenville-Spartanburg SC
1128 AM EDT Tue Apr 9 2019

.SYNOPSIS...
An area of low pressure system will cross the area today, bringing
another round of showers and thunderstorms to the region. Drier high
pressure will return on Wednesday before another cold front
approaches from the west later in the week.

&&

.NEAR TERM /THROUGH TONIGHT/...
As of 1125 am Tuesday: Have tweaked the forecast to adjust for the
latest trends in obs and model guidance. This continues to support
the highest PoPs and thunderstorm potential from the escarpment and
points SE, especially this afternoon into the early evening. Some
clearing is occurring north of I-85 in the Upstate of SC and NE GA
and across the NC mountains. These areas and others that have at
least some clearing will have higher CAPE values and therefore
better chances of thunderstorms. Short term models (i.e HRRR)
support this idea with convection initiating off the Blue Ridge mtns
early this afternoon and slowly propagating southeast into this
evening before weakening. Strong to potentially severe thunderstorms
will be possible (SPC placed east of mtns in marginal risk) with
large hail followed by gusty winds being the primary concerns.
However, minor flooding can't be ruled out with slower or training
of cells.

Otherwise, looks like another convectively-active day. Extensive low
clouds and fog early this morning should be able to burn off during
the middle part of the morning, followed by destabilization in the
late morning that fuels the development of new storms. Temps should
climb up to the mid/upper 70s. An old upper low moving east this
morning over the southeast will open up and cross our region this
afternoon with weakening mid/upper forcing. The relative lack of
synoptic forcing should be made up by better instability as compared
to yesterday given colder air aloft. The guidance shows sfc-based
CAPE climbing up toward 1500-2000 J/kg across the area east of the
Blue Ridge by afternoon, which should allow for vigorous updrafts
similar to yesterday. We will not see as much shear, however, which
suggests less of a wind damage threat, but still enough shear to
loosely organize the storms. Fcst soundings show a fatter CAPE
profile and wet-bulb zero height about 2K feet lower, so our large
hail potential looks better. The SPC has put most of the region
along and S/E of I-85 in a Slight Risk and if anything, it might
need to pushed even farther west up to the escarpment. My
expectation is for storms to fire over the mtns during the middle of
the day and then move out over the foothills and Upstate/wrn
Piedmont in the afternoon with hail-producing multicells. The
movement of the remaining short wave should carry the storms to our
east shortly after sunset, thereafter we can expect clearing from
the W/NW. Temps will still be at least five degrees above normal
overnight, though.

&&

.SHORT TERM /WEDNESDAY THROUGH FRIDAY NIGHT/...
As of 300 AM EDT Tuesday: The short term begins Wednesday morning,
with the weakening shortwave moving offshore and surface high
pressure dominating the region. Upper ridging building into the
center of the country will push east during the day, and the
increasing thicknesses will offset some of the weak low-level CAA,
leading to temperatures slightly above normal but cooler than today.

Meanwhile a strong midlevel low will push off the Rockies, with an
impressive surface low deepening over the Central Plains. High
pressure will continue over our area for Thursday, but the Plains
system will begin to occlude and drag a very strong front through
the Southern Plains and MS Valley Thursday night. Precip should
begin across the mountains as flow around the high pressure, now off
in the Atlantic, leads to upslope showers in the warm sector ahead
of the front. The good news is that the upslope flow will help to
offset the low-level WAA, but still should see mid to upper 70s
across the Piedmont on Friday. The upper jet will be weakening
somewhat as the upper low begins to fill as it lifts NE, but LLJ
along with strong dPVA will lead to 60-70kt deep layer shear at peak
heating Friday afternoon. Right now CAPEs are progged below 1000
J/kg, but 700 J/kg combined with 70kt shear can certainly lead to
severe weather concerns. As alluded to above, surface instability,
limited by morning upslope cloud cover and precip, will be the
limiting factor, but the lift with the front may easily overcome
that. The HWO is currently carrying mention of severe possible for
Friday and will evaluate SPC Day 4-8 outlook before deciding whether
to keep it or remove it. QPF is not all that impressive for this
event, with the more significant QPF Thursday night into Friday
associated with the Upslope flow.

The front won't quite make it through the area, stalled by the
Bahamas upper ridge and weakening overnight Friday night, but will
merge with another strong, more southerly system coming out of the
Desert Southwest into the Southern Plains for the weekend.

&&

.LONG TERM /SATURDAY THROUGH MONDAY/...
As of 310 AM EDT Tuesday: The aforementioned nearly stationary front
will be laid out across the area as we start the extended forecast
Saturday morning, with isolated shower activity possible during the
day. Very little change in temperatures going into Saturday
afternoon, with the above-normal streak (in the warm sector)
continuing.

As the Southern Plains system develops, another impressive surface
low is progged to move across the Lower MS Valley Saturday night.
Warm frontal/upslope precip will continue to blossom across our area
Saturday night. Weak surface high over SE Canada under the confluent
flow aloft will try to ridge down the eastern slopes of the
Appalachians, and guidance is developing a bit of an insitu damming
on Sunday. If this occurs, placement of the wedge front will be
critical for convection on Sunday afternoon, as the cold front again
will push through the area during prime peak heating. More CAPE
looks to be available with this secondary front, but the stronger
shear will be displaced more to the west - except of course for the
shear along the wedge front. Impossible to get into the details at
this point but we will need to monitor the forecast for Sunday
closely. QPF more impressive with this system as well, with current
guidance bringing 1.5-2" rain to the upslope areas and western
Upstate just Sunday alone, with 2-4" storm total in these same areas.

This front looks to actually clear the area, so we'll get a break
from the humidity and revert back to normal (or even below-normal)
lows at the end of the period.

&&

.AVIATION /16Z TUESDAY THROUGH SATURDAY/...
At KCLT and elsewhere: Fourth morning in a row with numerous
restrictions across the western Carolinas, but fortunately
things seem to have settled on mainly LIFR ceiling...with some
MVFR/VFR holes mixed in. The guidance once again supports the
restrictions ending fairly quickly in the 14Z-15Z time frame
once the sun gets to work on the air mass, but ongoing precip
might impact that timing. Once again, there are indications of
two rounds of precip...one through the late morning moving up
from the south, followed by another developing over the mtns in
middle of the day and moving east across the foothills/Piedmont
in the afternoon. All TAFs reflect that sort of thinking, but
with the primary thunderstorm restrictions associated with the
convection that moves off the mtns in the afternoon. Wind should be
SW and light outside of thunderstorm outflows. The guidance has the
activity moving east with a front late in the day, after which the
low clouds scatter out and the wind comes around to NW to N. There
could be some mtn valley fog at KAVL around daybreak Wednesday,
but otherwise the TAFs should all be VFR after about sunset.

Outlook: VFR conditions through at least early Thursday. Another
front is expected to bring at least brief restrictions and shower
chances Thu night through Friday.

Confidence Table...

            15-21Z        21-03Z        03-09Z        09-12Z
KCLT       High  81%     High 100%     High 100%     High  91%
KGSP       High  89%     High 100%     High 100%     High 100%
KAVL       Med   66%     High 100%     High 100%     High  83%
KHKY       High  91%     High 100%     High 100%     High 100%
KGMU       High  91%     High 100%     High 100%     High 100%
KAND       High  85%     High  96%     High 100%     High 100%

The percentage reflects the number of guidance members agreeing
with the scheduled TAF issuance flight rule category. Complete hourly
experimental aviation forecast consistency tables and ensemble forecasts
are available at the following link:

www.weather.gov/gsp/aviation

&&

.GSP WATCHES/WARNINGS/ADVISORIES...
GA...None.
NC...None.
SC...None.

&&

SYNOPSIS...Munroe/TDP
NEAR TERM...PM
SHORT TERM...TDP
LONG TERM...TDP
AVIATION...PM

Hazardous Weather Outlook
National Weather Service Greenville-Spartanburg SC
420 AM EDT Tue Apr 9 2019

GAZ010-017-018-026-028-029-NCZ033-035>037-048>053-056>059-062>065-
068>072-082-501>510-SCZ001>014-019-100830-
Rabun-Habersham-Stephens-Franklin-Hart-Elbert-Avery-Alexander-
Iredell-Davie-Madison-Yancey-Mitchell-Swain-Haywood-Buncombe-Catawba-
Rowan-Graham-Northern Jackson-Macon-Southern Jackson-Transylvania-
Henderson-Cleveland-Lincoln-Gaston-Mecklenburg-Cabarrus-Union-
Caldwell Mountains-Greater Caldwell-Burke Mountains-Greater Burke-
McDowell Mountains-Eastern McDowell-Rutherford Mountains-
Greater Rutherford-Polk Mountains-Eastern Polk-Oconee Mountains-
Pickens Mountains-Greenville Mountains-Greater Oconee-
Greater Pickens-Greater Greenville-Spartanburg-Cherokee-York-
Anderson-Abbeville-Laurens-Chester-Greenwood-
420 AM EDT Tue Apr 9 2019

This Hazardous Weather Outlook is for northeast Georgia, piedmont
North Carolina, western North Carolina and upstate South Carolina.

.DAY ONE...Today and tonight.

Showers and thunderstorms are expected to develop again today, and
some thunderstorms may become severe this afternoon and evening. The
main threats will be large hail and cloud to ground lightning, but
strong to damaging winds will be possible as well. Locally heavy
rainfall can be expected, and isolated flash flooding cannot be ruled
out.

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

Additional rounds of thunderstorms, some possibly strong, are expected
Friday and again on Sunday.

.SPOTTER INFORMATION STATEMENT...

None.

Special Weather Statement
National Weather Service Greenville-Spartanburg SC
1226 PM EDT Tue Apr 9 2019

GAZ017-018-026-028-091715-
Hart GA-Franklin GA-Stephens GA-Habersham GA-
1226 PM EDT Tue Apr 9 2019

...A STRONG THUNDERSTORM WILL IMPACT FRANKLIN...STEPHENS...
SOUTHEASTERN HABERSHAM AND NORTHWESTERN HART COUNTIES UNTIL 115 PM
EDT...

At 1226 PM EDT, Doppler radar was tracking a strong thunderstorm 4
miles northeast of Homer, moving northeast at 20 mph.

Locations to be impacted include...
Toccoa, Carnesville, Lavonia, Gumlog, Martin, Avalon, Boydville and
Eastanolee.

Wind gusts up to 50 mph and dime size hail will be possible in these
areas.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

This storm may intensify, so be certain to monitor local radio and tv
stations, as well as local cable tv outlets for additional
information and possible warnings from the National Weather Service.

&&

LAT...LON 3433 8339 3443 8338 3446 8340 3449 8349
      3469 8339 3443 8300 3426 8334
TIME...MOT...LOC 1626Z 214DEG 16KT 3437 8343

SGL