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Area Forecast Discussion (AFD)

Issued by Charleston, SC (CHS)

                            
000
FXUS62 KCHS 220543
AFDCHS

Area Forecast Discussion
National Weather Service Charleston SC
143 AM EDT Fri Mar 22 2019

.SYNOPSIS...
A cold front will move offshore tonight. High pressure will 
build over the region on Friday and will linger through this 
weekend. Low pressure may move across the region on Monday night
through Tuesday night. 

&&

.NEAR TERM /UNTIL 6 AM THIS MORNING/...
Early this morning: Surface analysis shows that the secondary 
cold front is poised to push through the forecast area over the 
next few hours. Satellite imagery shows that this front will 
bring few to scattered mid level clouds with it for southeast 
South Carolina, followed by clear skies. The forecast is very 
quiet through sunrise. 

&&

.SHORT TERM /6 AM THIS MORNING THROUGH SUNDAY/...
An elongated area of high pressure sourced from central Canada 
will begin to build over the region on Friday. The center of the
high is forecast to settle over the forecast area Saturday and 
Saturday night. The high will slide off the Carolina coast on 
Sunday. The weather through the period will be dry with clear to
mostly clear sky conditions. Daytime temperatures will peak 
around 70 with morning lows in the 40s, warmest conditions on 
Sunday.

&&

.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
A broad low pressure system is forecast to track across the 
region Monday night through Tuesday night. I will increase PoPs 
during the period and will introduce SCHC for thunderstorms 
Tuesday afternoon and evening. Cold air advection in the wake of
the low may result in upper 30s inland early Wednesday morning.
Sfc high pressure is expected to dominate the region Wednesday 
and Thursday.

&&

.AVIATION /06Z FRIDAY THROUGH TUESDAY/...
VFR conditions will prevail at both KCHS and KSAV through 06Z 
Saturday. Westerly winds will become gusty late this morning and
this afternoon, with frequent gusts into the 20-25 knot range. 

Extended Aviation: VFR through Sunday. Flight restrictions are 
possible Tuesday and Tuesday night. VFR conditions return on 
Wednesday.

&&

.MARINE...
Tonight: A dry cold front will continue to push through the 
southern and central waters this evening, then eventually 
through the northern waters by midnight. Large isallobaric 
pressure rises and decent mixing of 30 kt of geostrophic winds 
supports expanding the Small Craft Advisory headlines to now 
include all Atlantic zones. W-NW winds will reach 20-25 kt with 
gusts to near 30 kt at times over the ocean, while seas climb as
high as 3-5 ft within 20 nm and up to 7 ft further out. 
Charleston Harbor will come close to advisory thresholds, but 
for the present time conditions look to fall just shy. 

Extended Marine: High pressure will build over the marine zones
Friday through Saturday, yielding winds generally below 15 kts.
A short window of gusty winds are possible Friday evening. Seas
are expected to range between 2 to 4 ft. Low pressure is 
forecast to track near the region on Tuesday and Tuesday night. 
In the wake of the low, gusty NE winds are expected across the 
marine zones. Small Craft Advisory conditions may begin on 
Tuesday and remain through Wednesday.

Rip Currents: A moderate risk for rip currents will continue 
along the beaches through Friday evening. Surf is forecast to 
feature 2 ft with 10 second periods. Northwest winds are 
expected during the morning Friday, then will shift from the 
west.

&&

.FIRE WEATHER...
Friday: RH values as low as 25-30 percent and elevated offshore
winds could also cause fire concerns, especially if partners 
report low fuel moisture.

&&

.EQUIPMENT...
The KCLX radar has failed. Technicians will look into the issue
this morning.

&&

.CHS WATCHES/WARNINGS/ADVISORIES...
GA...None.
SC...None.
MARINE...Small Craft Advisory until 4 AM EDT early this morning for 
     AMZ352-354.
     Small Craft Advisory until noon EDT today for AMZ374.
     Small Craft Advisory until 6 AM EDT early this morning for 
     AMZ350.

&&

$$

NEAR TERM...BSH
SHORT TERM...NED
LONG TERM...NED
AVIATION...BSH/NED
MARINE...33/NED
FIRE WEATHER...
EQUIPMENT...