FXUS62 KCHS 281132 AFDCHS
Area Forecast Discussion National Weather Service Charleston SC 632 AM EST Wed Jan 28 2026
.WHAT HAS CHANGED...
The aviation section was updated for the 12z TAFs.
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.KEY MESSAGES...
- 1) Unseasonably cold weather will occur through early next
week.
- 2) Developing low pressure offshore could bring snow to parts
of the region this weekend.
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.DISCUSSION...
KEY MESSAGE 1...Unseasonably cold weather will occur through early next week.
Arctic high pressure over the area will slowly moderate as it shifts southeast through Friday. Temps and wind chill values are forecast to remain above Cold Weather Advisory criteria during this time.
A particularly strong, 1050 mb high will drop out of central Canada Friday, then spread into the Southeast Friday night and Saturday. This will usher in much colder air, along with 10-15 mph surface winds. Saturday highs are expected to be in the upper 30s inland to lower 40s coastal. Temps will quickly decrease late Saturday afternoon, with wind chills dropping below 20 degrees by 6pm. Saturday night lows in the mid to upper teens combined with 10-15 mph NW winds will produce 0-10 degree wind chills much of the night, likely necessitating an Extreme Cold Warning.
Sunday highs will be in the upper 30s in most areas. Sunday night may require a Cold Weather Advisory as lows in the upper teens to lower 20s and 5-10 mph wind could produce wind chills of 10-20 degrees. Temperatures steadily warm up early next week.
KEY MESSAGE 2:...Developing low pressure offshore could bring snow to parts of the region this weekend.
Models continue to be in rather good agreement regarding the synoptic set up this weekend. A sharp trough is forecast to dig southward out of the Great Lakes on Friday, dropping into the southeastern states Saturday. Simultaneously a surface low is forecast to develop off the southeastern coast before trekking to the northeast. Precipitation along the backside of the low could impact the region within the timeframe of Friday night through Sunday morning. While there is high confidence in the synoptic forecast, the finer details remain a very low confidence forecast.
There are two main possible scenarios A) the upper low digs further south with surface cyclogenesis occurring further south (favorable for greater precipitation chances) and B) the upper low remains further northward with surface cyclogenesis occurring further to the north (lesser precipitation chances). The 00Z ECMWF Ens and the GEFS both support scenario A, however we would like to see more run-to- run consistency of the ensembles and deterministic guidance before latching onto either scenario. It is worth noting that the air mass in place this weekend will be very cold (see Key Message 1). Therefore, if there is any precipitation we would not be dealing with many precipitation type issues, just a rain/snow forecast.
The forecast will continue to explicitly advertise rain/snow but it continues to be too early to attempt to nail down the likelihood, timing, extend, and magnitude of any snow accumulations.
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.AVIATION /12Z WEDNESDAY THROUGH SUNDAY/...
VFR conditions will prevail through the 12Z TAF period.
Extended Aviation Outlook: Predominantly VFR through the extended period, with increasing potential for impacts Saturday associated with developing low pressure offshore of the Southeastern coast.
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.MARINE...
Confidence is increasing in a potentially significant coastal system this weekend with the potential for Gales over most of the marine area. N to NW winds will be increasing Friday night, with the strongest winds potentially occurring Saturday through Sunday before the developing coastal low moves northeast. We could see sustained winds approaching 34 kt with frequent gusts of 35-40 kt over all coastal waters, and 30 kt gusts in Charleston Harbor during this time.
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.CLIMATE...
Record Low Temperatures:
January 31: KCHS: 15/1966 KCXM: 19/1966 KSAV: 16/1966
February 1: KCHS: 21/1977 KCXM: 23/1900 KSAV: 23/1977
February 2: KCHS: 19/1980 KCXM: 17/1917 KSAV: 18/1917
Record Low Maximum Temperatures:
January 31: KCHS: 36/1948 KCXM: 34/1936 KSAV: 37/1909
February 1: KCHS: 38/1980 KCXM: 36/1900 KSAV: 38/1900
February 2: KCHS: 38/1980 KCXM: 38/1898 KSAV: 38/1951
Record Snowfall:
January 31: KCHS: 0.6/1977 KSAV: 1.3/1977
February 1: KCHS: no record established KSAV: no record established
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.EQUIPMENT...
The KCLX radar remains out of service. There has been a delay in the arrival of replacement parts due to extreme weather over parts of the country. The currently anticipated return to service is Thursday January 29th. Users should use adjacent WSR-88D sites, including KCAE, KLTX, KJAX, KVAX and KJGX.
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.CHS WATCHES/WARNINGS/ADVISORIES...
GA...None. SC...None. MARINE...None.
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CPM/JRL