Area Forecast Discussion
Issued by NWS Columbia, SC

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50
000
FXUS62 KCAE 241431
AFDCAE

Area Forecast Discussion
National Weather Service Columbia SC
1031 AM EDT Sat Jun 24 2017

.SYNOPSIS...
A slow moving cold front will be in the region through Monday.
Showers and thunderstorms will be associated with the front
especially just ahead of the feature this afternoon and
evening. Drier and cooler weather will follow the front by the
middle of next week.

&&

.NEAR TERM /THROUGH TONIGHT/...
Update 1035 am - A slow moving cold front will sag into east
central Georgia and central South Carolina this afternoon and
evening. Satellite and radar imagery showed an upper trough
digging into northern Mississippi and Alabama which will spur
convection across eastern Georgia by early afternoon and central
South Carolina by mid afternoon. PW values well in excess of 2.0
inches provides an enivornment for localized flash flooding.
Current forecast is in good shape.

The slow moving front in the area supports numerous showers and
thunderstorms today and tonight. The high-resolution models
depict the greatest coverage this afternoon and evening.
The NAM and GFS indicate weak to moderate instability with
surface-based LI values -5 to -8. The GFS was most unstable but
may be overdone because of cloudiness. Still, heavy precipitation
loading associated with precipitable water peaking around 2.3
inches supports a possibility of damaging wind with the
thunderstorms. There should be less of a damaging hail threat
with high wet-bulb zero heights. Most of the guidance indicates
general rain totals through tonight of 0.5 to 1 inch. However,
based on the high precipitable water locally heavier rainfall
amounts and high rates may occur with localized flooding
possible. We held off posting a flash flood watch for now
because of forecast storm movement and relatively high flash
flood guidance of over 3 inches in 3 hours over much of the
area. Followed the guidance consensus for the temperature
forecast.

&&

.SHORT TERM /SUNDAY THROUGH SUNDAY NIGHT/...
The models show the front lingering in the forecast area Sunday
and Sunday night with deeper moisture shifting east of the
area. The guidance consensus supports chance pops with the
greater values in the east section closer to deeper moisture.
The NAM and GFS display moderate instability in the southeast
section Sunday with surface-based LI values -6 to -7 supporting
a possibility of strong wind with thunderstorms. The temperature
guidance was close.

&&

.LONG TERM /MONDAY THROUGH FRIDAY/...
The GFS and ECMWF depict some surface troughing lingering
Monday and there may be increased moisture and instability
associated with a sharpening upper trough Tuesday. However,
deeper moisture should be east of the area. The GFS and ECMWF
MOS have pops 20 percent or less. The models are consistent
with dry ridging dominating during the middle of the week with
some moisture increase in an onshore flow late in the week.
Expect below normal temperatures especially Tuesday and
Wednesday as indicated by the GFS and ECMWF MOS.

&&

.AVIATION /15Z SATURDAY THROUGH WEDNESDAY/...
Generally high confidence for VFR conditions at least into the
afternoon hours.

Good low-level mixing early this morning so fog is not an issue.
Scattered storms expected to affect the TAF sites by early
afternoon ahead of a slow moving cold front. Strong gusty winds
possible with storms in addition to cig/vsby restrictions.
Convection should diminish later this evening.

EXTENDED AVIATION OUTLOOK...Cig/vsby restrictions may be
possible early Sunday.

&&

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

&&

$$
SYNOPSIS...99
NEAR TERM...99
SHORT TERM...99
LONG TERM...99
AVIATION...99


USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.