Area Forecast Discussion
Issued by NWS Charleston, SC
Issued by NWS Charleston, SC
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400 FXUS62 KCHS 081731 AFDCHS Area Forecast Discussion National Weather Service Charleston SC 1231 PM EST Sat Nov 8 2025 ...A WIDESPREAD FREEZE IS LIKELY MONDAY NIGHT WITH WIND CHILLS DROPPING INTO THE UPPER TEENS TO 20S... .SYNOPSIS... High pressure will extend across the region through the weekend. A strong cold front will move through Sunday night bringing much colder conditions to the area next week. && .NEAR TERM /THROUGH TONIGHT/... This Afternoon: Convection continues to meander northeast ahead of a 850-700 hPa shortwave propagating east/northeast across Georgia. Modified RAP soundings yield moderate levels of instability with SBCAPE 1500-2000 J/kg with in a moderately sheared environment featuring 0-6km bulk shear values around 40 kt. Although mid-level lapse rates will remain fairly muted, a few strong tstms can not be ruled out later this morning and especially this afternoon as surface temperatures rise and low- level lapse rates increase. Gusty winds and small hail are the most likely hazards. The risk for tstms reaching severe levels remains low given the less than ideal mid-level lapse rates. This activity should begin to wane by late afternoon as the aforementioned shortwave exits to the north and UVVs diminish. Tonight: A broad southwest flow will prevail across the Southeast U.S. tonight as high pressure shifts farther east out into the Atlantic and the mean upper-level flow veers ahead of a powerful shortwave that will dig across the Central Plains. The combination of a modest wind field aloft coupled with a tightening pressure gradient between the departing high, a weak low over Virginia and an approaching strong cold front will keep the boundary layer fairly well mixed through the night. This will result in a fairly warm night for the region with the pre- frontal warm sector with lows poised to only drop into the lower 60s well inland to the mid 60s at the coast. A few showers owing to lingering warm air advection/isentropic ascent will keep a risk for some measurable rainfall into early Sunday morning, mainly across the interior. Pops 20-30% were highlighted inland to account for this, but the QPF should remain fairly light. && .SHORT TERM /SUNDAY THROUGH TUESDAY/... An unseasonably strong upper low will dive into the Great Lakes region on Sunday with the longwave trough extending to the central Gulf Coast. A strong cold front will sweep through the local area Sunday evening. Fairly strong warm advection ahead of the front, along with pre-frontal compression, will result in a warm day with highs in the upper 70s to lower 80s. Moisture advection ahead of the front looks weak, and instability will be limited. Large scale subsidence may overspread the area before the front makes it through, limiting the potential for upward vertical motion and convective development. It`s still possible that a thin, broken band of showers or isolated tstms could move through immediately ahead of the cold front. The cold front will push offshore late Sunday evening, with strong cold advection expected across the forecast area through the rest of the night. Lows could dip below 40 far inland, with upper 40s closer to the SC/GA coast. Strong cold advection will continue Monday into Tuesday. Highs Monday and Tuesday will generally be in the lower 50s. Monday night into Tuesday morning we expect a solid freeze across the area, potentially all the way to the beaches. Also, in pockets of southeast GA the wind chill could briefly dip below 20 degrees, triggering a Cold Weather Advisory. Freeze headlines are likely to be needed for the entire forecast area Monday night. && .LONG TERM /TUESDAY NIGHT THROUGH FRIDAY/... Tuesday night, clear sky with light to calm winds should provide strong radiational cooling conditions through the night. Low temperatures should fall to around 30 degrees along and west of I-95, with mid to upper 30s to the east. Winds might weaken enough to allow frost development as well. Temperatures should trend warmer through the rest of the work week. In fact, temperatures should return to mid November normals by Thursday, remaining near normal through the rest of the forecast period. Conditions should remain dry under NW mid- level flow. && .AVIATION /15Z SATURDAY THROUGH WEDNESDAY/... 08/18z TAF Discussion: KCHS/KJZI: Convective trends with activity moving across Southeast Georgia is being closely monitored. Near term guidance suggests much of this may diminish prior to reaching KCHS and KJZI in the 19-20z time frame. VCSH may hold for now, but a last minute change may be needed pending radar trends at issuance time. Otherwise, VFR will prevail for much of the 18z TAF cycle. There are some indications that an area of low stratus could develop over the Midlands early Sunday morning ahead of the approaching cold front. Some of this could expand into Southeast South Carolina and possibly KCHS prior to daybreak. Confidence on how far south and/or southeast this area of stratus will get is unclear, so it was not mentioned for the 18z TAF cycle given only the 08/12z NAM statistical guidance was pinging a brief period of MVFR or lower cigs right at daybreak. KSAV: Convection will be close to or exiting KSAV by 18z as the main area of showers/tstms meanders northeast. Some mention of TSRA may need to be held onto pending last minute radar trends. Otherwise, VFR conditions will prevail for much of the 18z TAF period. There are some signals that an area of low stratus could expand northeast out of the Florida Panhandle and into Southeast Georgia just before daybreak Sunday. Confidence on whether stratus will reach KSAV remains fairly low and there are mixed outcomes noted in this morning`s statistical guidance, so no mention of MVFR or lower cigs were introduced for this cycle. This will be reevaluated for the 09/00z TAF cycle. Extended Aviation Outlook: Gusty NW winds Monday and Monday evening. && .MARINE... Through Tonight: There are no concerns. South winds will veer to the southwest overnight with speeds increasing to 10-15 kt nearshore waters and 15-20 kt over the Georgia offshore waters. There could be a few gusts near 25 kt over the Georgia offshore waters and the far eastern portions of the South Santee-Edisto Beach nearshore leg, but durations do not look long enough to support a Small Craft Advisory at this time. Seas will average 4 ft or less. Sunday through Wednesday: SW winds Sunday will turn to the NW and increase Sunday night behind a strong cold front. The strongest marine winds are expected Monday through Tuesday during which solid Small Craft Advisory conditions will occur. We could see gusts near Gale force Sunday night for the offshore GA waters and nearshore Charleston County waters. Conditions gradually improve after Tuesday. && .CLIMATE... Upcoming Record Low Temperatures: November 11 (Tuesday): KCHS: 29/1943 KCXM: 32/1913 KSAV: 31/1968 November 12 (Wednesday): KCHS: 27/1943 KCXM: 33/1894 KSAV: 30/2011 Upcoming Record Low Maximum Temperatures: November 10 (Monday): KCHS: 46/1991 KCXM: 47/1991 KSAV: 49/1968 November 11 (Tuesday): KCHS: 54/1968 KCXM: 46/1913 KSAV: 49/1913 && .CHS WATCHES/WARNINGS/ADVISORIES... GA...None. SC...None. MARINE...None. && $$