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Area Forecast Discussion (AFD)

Issued by Charleston, SC (CHS)

                            
000
FXUS62 KCHS 230406
AFDCHS

Area Forecast Discussion
National Weather Service Charleston SC
1206 AM EDT Tue Apr 23 2019

.SYNOPSIS...
High pressure will prevail with dry weather through Thursday.
Low pressure and a cold front will then bring unsettled weather
late this week into the weekend. 

&&

.NEAR TERM /UNTIL 6 AM THIS MORNING/...
No meaningful changes were made for the midnight update. 

&&

.SHORT TERM /6 AM THIS MORNING THROUGH THURSDAY/...
Tuesday through Thursday: Subsidence provided by deep layered high 
pressure will support high temperatures in the lower/middle 80s 
Tuesday, then temperatures will warm further into upper 80s/close to 
90F away from the beaches Wednesday and Thursday. Expect low 
temperatures in the mid/upper 50s inland and lower 60s close to the 
coast Tuesday night, followed by low temperatures around 60F inland 
and in the lower/middle 60s closer to the coast Wednesday night. 
Within the westerly flow aloft, patchy high clouds will stream 
across the region at just about anytime through Wednesday. Then, 
thicker cirrus could spread across the region Thursday. Otherwise, 
expect nothing more than scattered diurnal cumulus especially 
Wednesday/Thursday, and the chance for measurable rainfall will 
remain essentially zero through this period.

&&

.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
A storm system with its associated cold front is expected to move 
through the region on Friday, bringing showers and cooler 
temperatures. However, models disagree on the track and timing of 
the main features along with the main bands of rainfall.
Hence, we have chance POPs in the forecast. By the weekend the 
models continue to differ on whether it will be dry or if showers 
will persist. We opted to go with slight chance POPs to account for 
this.

&&

.AVIATION /04Z TUESDAY THROUGH SATURDAY/...
VFR. Shallow ground fog is possible at both KCHS and KSAV, but
no impacts are expected.

Extended Aviation Outlook: VFR through Thursday, with 
only a low probability for ground fog around sunrise each day. 
Then, low pressure, a cold front and showers/thunderstorms could
produce periodic flight restrictions Friday into Saturday.

&&

.MARINE...
Tonight: A minimal gradient will prevail with high pressure 
overhead. S or SW winds on the South Carolina waters and SE on 
the Georgia waters early on will move to the SW and W overnight
and late with land breeze influences. Speeds will be around 5-10
kt. Seas will average 1-2 ft near shore and 2-3 ft over the
Georgia offshore waters.

Tuesday through Saturday: Under high pressure, the sea breeze 
circulation featuring winds of 15 knots or less will dominate local 
winds Tuesday afternoon/early evening. Seas will average 1-3 feet, 
highest beyond 20 nm. Then, a tightening pressure gradient will 
support somewhat stronger southwest synoptic winds especially 
Wednesday through Thursday, and the south/southwest sea breeze could 
locally gust as high as 15-20 knots. Seas will respond and will 
average 2-4 feet. A cold front will then move through the region 
sometime between Friday afternoon and late Friday night, followed by 
a wind shift to the northeast by Saturday. Winds/seas could approach 
SCA levels Saturday.

&&

.CHS WATCHES/WARNINGS/ADVISORIES...
GA...None.
SC...None.
MARINE...None.

&&

$$