175 FXUS62 KCHS 131556 AFDCHS Area Forecast Discussion National Weather Service Charleston SC 1056 AM EST Sat Jan 13 2024 .SYNOPSIS... High pressure will prevail this weekend. Low pressure could then impact the Southeast early next week, before high pressure prevails during the middle of next week. Another low pressure system could impact the area late next week before more high pressure returns next weekend. && .NEAR TERM /THROUGH TONIGHT/... Update: Temperatures are several degrees warmer than what was anticipated, notably along the coast. We redid the hourly temperatures through this afternoon, having highs peak in the mid 50s, mainly due to clouds and cold air advection. Meanwhile, dew points are much lower than expected, so we lowered them into this afternoon. Otherwise, a cold front is far offshore and moving away from our area. In the wake of the front, gusty winds will shift from the WNW and CAA should continue through the daylight hours today. The WNW winds are forecast to gusts between 25-30 mph the rest of this morning, then gradually ease this afternoon. A Lake Wind Advisory will remain in effect until 1 PM. High temperatures are forecasted to range between 52-57 degrees. Tonight, the center of weak high pressure will remain centered over the Deep South. The axis of a H5 longwave trough will ripple over the forecast area late tonight. The core of H25 160 kt jet will slide over the forecast area by daybreak Sunday. Mid and high clouds should keep sky cover at least partly cloudy through the night. Low temperatures are forecast to range from the low 30s inland to the upper 30s along the coast. && .SHORT TERM /SUNDAY THROUGH TUESDAY/... Sunday: Aloft, the mid-upper flow remains primarily zonal south of a large/broad trough stretched across the Great Lakes and Northeast. At the sfc, high pressure centered across the Deep South will slowly nudge east, favoring dry and slightly warmer conditions under the west-southwest flow aloft. High temps should peak in the upper 50s to around 60 degrees. Guidance suggests a weak/dry cold front shifting across the area overnight, having little impact in regards to low temps, which should dip into the low-mid 30s away from the coast. Monday and Tuesday: Sfc low pressure should develop/strengthen across the northeast Gulf and/or the western Atlantic off the Southeast Coast as h5 shortwave energy ripples across the region while a 130-140 kt h25 jet remains positioned across the Southeast. Latest guidance suggests sufficient moisture returning from the south-southwest by Monday afternoon, leading to few/scattered showers across southeast Georgia into southeast South Carolina. Mid- upper lvl dynamics will remain supportive of rain/showers Monday night into Tuesday as long as moisture remains sufficient. Scattered to numerous showers are possible along the immediate coast Monday night, but a gradual diminishing trend is expected as the low pressure system/trough nudges further offshore Tuesday. Breezy conditions could also setup across the region in wake of the system/trough shifting further offshore Tuesday afternoon/evening. Despite increasing clouds and showers on Monday, warm air advection should support highs in the upper 50s/lower 60s. Monday night lows will also be noticeably warmer than the previous night, only dipping into the low-mid 40s. Temps will be cooler on Tuesday as winds shift offshore and cold air advection takes place locally. High temps should peak in the low-mid 50s Tuesday afternoon. && .LONG TERM /TUESDAY NIGHT THROUGH FRIDAY/... Considerably colder air is expected to advect across the region Tuesday night as a high amplitude trough sweeps across the East CONUS heading into mid week. The combination of breezy winds and overnight low temps in the low-mid 20s could produce some wind chill concerns away from the coast heading into Wednesday morning. A Wind Chill Advisory could eventually be needed. Cold conditions will prevail through Wednesday with high temps only peaking in the low- mid 40s and overnight lows dipping into the mid-upper 20s away from the coast Wednesday night. However, winds should become lighter at night and limit wind chill concerns. A gradual warm-up will follow during the second half of next week as the mid-upper lvl trough shifts offshore while sfc high pressure prevails locally. However, high temps should still remain below normal, ranging in the low-mid 50s Thursday, then mid-upper 50s Friday. A low pressure system could impact parts of the Southeast heading into next weekend, followed by even colder high pressure building across the East CONUS. Temps could struggle to reach the low-mid 40s locally next Saturday with overnight lows in the low-mid 20s. && .AVIATION /16Z SATURDAY THROUGH WEDNESDAY/... 16Z Update: VFR. Winds will remain from the WNW with frequent gusts between 20-25 kt through late afternoon. Mixing heights and the pressure gradient will decrease by 22Z, ending a mention of gusts. After sunset, winds are forecast to remain light and steady from the west. Extended Aviation Outlook: VFR conditions are expected at CHS/JZI/SAV terminals through early Monday. Tempo flight restrictions are possible at all terminals due to rain/showers Monday afternoon into Tuesday. Breezy winds are also possible at all terminals Tuesday and Tuesday night with the passage of a cold front. && .MARINE... Rest of Today: A cold front is far offshore and moving away from our waters. In the wake of the front, gusty winds will shift from the WNW and CAA should continue through the daylight hours today. Small Craft Advisory (SCA) winds and seas will remain across all marine zones through early this afternoon. Conditions will improve late this afternoon. Tonight, high pressure will remain centered over the Deep South. The sfc pattern should yield NW winds between 10-15 kts. Seas will decrease to 1-2 ft by daybreak Sunday. Sunday through Thursday: High pressure will prevail across local waters on Sunday with winds/seas expected to remain well below Small Craft Advisory levels. Low pressure should then develop across the northeast Gulf and/or just off the Southeast Coast Monday into Tuesday, before shifting further offshore late Tuesday through Wednesday. As this process unfolds, the pressure gradient will strengthen across local waters while a steady stream of cold air advection occurs across the area behind the departing trough. Small Craft Advisories could be needed across most waters Tuesday night into early Wednesday. High pressure should then prevail across the region Thursday with a weaker pressure gradient in place. Expect winds/seas to return below Small Craft Advisory levels heading into the second half of next week. && .TIDES/COASTAL FLOODING... Abnormally low water levels are expected this afternoon around low tide, between 230 PM and 430 PM EST. Low tide will occur at 334 PM. Gusty offshore winds combined with astronomically low tides will lead to water levels falling to around -1.5 ft MLLW. Low water levels can lead to difficult navigation and stronger currents in tidal creeks and waterways. && .CHS WATCHES/WARNINGS/ADVISORIES... GA...None. SC...Lake Wind Advisory until 1 PM EST this afternoon for SCZ045. MARINE...Small Craft Advisory until 1 PM EST this afternoon for AMZ330- 354. Small Craft Advisory until 7 PM EST this evening for AMZ350. Small Craft Advisory until 4 PM EST this afternoon for AMZ352- 374. && $$ NEAR TERM... SHORT TERM...DPB LONG TERM...DPB AVIATION...DPB MARINE...DPB TIDES/COASTAL FLOODING...