Area Forecast Discussion
Issued by NWS Charleston, SC
Issued by NWS Charleston, SC
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
174 FXUS62 KCHS 111919 AFDCHS Area Forecast Discussion National Weather Service Charleston SC 319 PM EDT Sat May 11 2024 .SYNOPSIS... High pressure will prevail into Monday. A storm system will affect the area by the middle of the week. Another system could arrive later in the week. && .NEAR TERM /THROUGH TONIGHT/... High pressure centered over the lower Mississippi Valley will extend across the Southeast U.S. tonight. A weak surface trough will drop south and approach the I-26 corridor around daybreak Sunday. The boundary layer will decouple quickly after sunset with any weak sea breeze that is pinned near the beaches rapidly breaking down. Diurnal cumulus will dissipate with the loss of insolation resulting in mainly clear skies. Clear skies, dry conditions and calm/light winds will promote strong radiational cooling. The colder side of the 11/12z temperature guidance envelope was favored with lows ranging from the mid 50s inland to the mid 60s at the beaches and Downtown Charleston. Sky conditions will be ideal for watching the aurora tonight. Refer to the latest aurora forecast from the National Weather Service`s Space Weather Prediction Center (www.swpc.noaa.gov) for the latest aurora and geomagnetic storm updates. && .SHORT TERM /SUNDAY THROUGH MONDAY/... Sunday will be another beautiful day with low humidity, seasonable temperatures, and a mix of sun and clouds. Highs peak in the low to mid 80s. Lows Sunday night range from the upper 50s across the interior to mid/upper 60s at the immediate coast. A mid level low and associated surface reflection will track from the Central Plains towards the East Coast Monday into Tuesday. Moisture steadily returns back to the area, with PWats eventually peaking over 1.75 inches which is well above climatological normals. While isolated to scattered showers and thunderstorms are possible Monday afternoon, higher coverage is expected later Monday night and especially on Tuesday when the better forcing arrives. Convective evolution is still uncertain, but severe weather potential will bear watching for Tuesday with forecast wind shear values (perhaps 40+ knots) supportive of storm organization. Best instability seems to be situated south of the Savannah River. Highs both days are forecast to be in the upper 70s to lower 80s. Lows stay in the 60s. && .LONG TERM /MONDAY NIGHT THROUGH FRIDAY/... Low pressure system moves off the mid-Atlantic coast Wednesday into Wednesday night. Showers and perhaps a few thunderstorms could develop during the day, but coverage should be more limited with rain chances only in the 20-30% range. Ridging briefly passes across the region Thursday before the next system potentially arrives late week into the weekend and brings rain chances back in the forecast. Temperatures through the period are generally near to above normal. && .AVIATION /18Z SATURDAY THROUGH THURSDAY/... 11/18z TAF Discussion: KCHS/KJZI/KSAV: VFR through 12/18z Sunday. Extended Aviation Outlook: Showers and thunderstorms could bring flight restrictions to the terminals Monday afternoon into the middle of next week. && .MARINE... Tonight: No concerns. Weak onshore winds will become more southwest overnight as a subtle surface trough drops in from the north. Speeds will remain less than 10 kt with seas 1-2 ft. Sunday through Thursday: No concerns over the marine area for Sunday into Monday. Winds will increase Monday night into Tuesday and will remain fairly gusty into Wednesday as low pressure tracks towards the East coast. Seas also build and while it looks fairly marginal at this time, there is potential for a period of Small Craft Advisories over portions of the waters, especially the outer Georgia and Charleston county waters. Conditions improve for Thursday. Rip Currents: A moderate risk for rip currents continues for the Georgia beaches until 8 PM as rip currents are being reported at Tybee Island. && .CHS WATCHES/WARNINGS/ADVISORIES... GA...None. SC...None. MARINE...None. && $$