textproduct: Charleston

WHAT HAS CHANGED

Winter weather headlines have been updated. Additional snow totals updated. New Cold Weather Advisory issued for tonight into Monday morning. New Key Message addressing rain chances for mid-week was introduced.

KEY MESSAGES

- 1) Impacts from the ongoing winter storm will continue. Additional minor accumulations are possible this morning along with areas of blowing snow.

- 2) Extremely cold temperatures are expected this weekend into early next week. Historic bitter cold will continue this morning.

- 3) A cold front will bring rain showers to the South Carolina Lowcountry and southeast Georgia late Tuesday night into Wednesday night.

DISCUSSION

KEY MESSAGE 1: Impacts from the ongoing winter storm will continue. Additional minor accumulations are possible this morning along with a continued risk for areas of blowing snow.

Light to moderate snow and areas of blowing snow persist across much of the Lowcountry into the lower Savannah River Valley early this morning. The last batch of snow associated with the broad deformation zone along the backside of the departing upper low will pivot across much of the Lowcountry over the next several hours bringing a risk for an additional 1-2". Although snows across interior Southeast Georgia have mostly ended, roads remain snow covered and hazardous travel conditions persist. Here is a summary of all winter-related headlines based on current travel conditions and expected snowfall:

1. Maintain all Winter Storm Warnings through 1 PM due to a combination of an additional 1-2" of snow over parts of the Lowcountry and ongoing hazardous travel over interior Southeast Georgia where the snow has ended.

2. Cancel the Winter Winter Weather Advisory for Tattnall, Long, Liberty and McIntosh where reports from County Warning Points indicate there are little, if any, significant travel issues.

3. Extend the Winter Weather Advisory until 10 AM for Evans, Bryan and Chatham Counties where hazardous travel persists due to some snow covered roads.

Dry but cold conditions will occur after the snow ends. The clearing line will move from southwest-northeast this morning and sunny skies will prevail today.

Lake Moultrie: Windy conditions persist on Lake Moultrie this morning with winds generally 25 kt with gusts 35 kt. Winds will slowly diminish through daybreak and should drop below Lake Wind Advisory criteria by late morning. There is a continued risk some freezing spray over the lake itself and along southern and southeastern lakeshore, including Pinopolis and Short Stay through daybreak. Some icing of piers, docks and structures along the lake could occur.

KEY MESSAGE 2: Extremely cold temperatures are expected this weekend into early next week. Historic bitter cold will continue this morning.

This morning single digit wind chills are common across the region this morning as temperatures fall into the teens. Minimum wind chills of 0-5 above zero are expected and an Extreme Cold Warning remains in place for all of the South Carolina Lowcountry and Southeast Georgia. For tonight, it will be warmer with lows dropping into the lower-mid teens inland to the mid- upper 20s closer to the coast. A combination of low temperatures and lingering wind chills will support a Cold Weather Advisory for all areas tonight into Monday morning.

Monday night, very light southwest winds are expected. Skies will start out clear in the evening, with clouds gradually increasing from south to north overnight. These clouds may limit some of the radiational cooling, mainly towards daybreak Tuesday. Lows should range from the lower 20s inland to near freezing at/near the beaches. Since winds will be very light, wind chills aren't forecasted to drop to 20 degrees or lower across most of our area. Therefore, we probably won't need a Cold Weather Advisory. Tuesday, temperatures moderate with highs ranging from near 50 degrees near the Santee River to the lower 60s near the Altamaha River.

KEY MESSAGE 3: A cold front will bring rain showers to the South Carolina Lowcountry and southeast Georgia late Tuesday night into Wednesday night.

The mid-levels Tuesday night will consist of a positively tilted trough axis stretching roughly from the Great Lakes region down into the Southern Plains. It'll gradually shift eastward, becoming located from the New England States down into the Deep South by Wednesday night. At the surface, High pressure off the Southeast U.S. Tuesday night will shift further offshore, while a cold front approaches from the west and northwest. There will be a decent plume of moisture ahead of the front, with PWATs peaking ~1.15" on Wednesday. This is close to the 90% mark for CHS, per SPC Sounding Climatology. Models are in fairly good agreement having rain showers overspreading our far inland areas late Tuesday night, then making it to the coast Wednesday morning. The highest POPs across our entire area are generally Wednesday afternoon. The cold front will quickly move through our area Wednesday night, with rain showers gradually dissipating from west to east. By daybreak Thursday, there could be a few isolated rain showers near the coast that will quickly move offshore. Storm total QPF should be in the 0.1-0.25" range. Temperatures are expected to stay warm enough at the surface and higher up to only generate rain showers. Low temperatures Tuesday night will be in the upper 30s to mid 40s. Highs Wednesday will range from the mid 50s to the lower 60s. Low temperatures Wednesday night will generally be in the mid to upper 30s, mainly reached towards daybreak Thursday.

AVIATION /06Z SUNDAY THROUGH THURSDAY/

01/06z TAF Discussion: KCHS/KJZI/KSAV: Prevailing MVFR cigs are expected through about 11Z Sunday with light snow also producing IFR vsbys temporarily between 06-09Z Sunday. VFR conditions will then prevail through 06Z Monday at all terminals. Winds will remain gusty from the northwest at all terminals, peaking between 20-25 kt tonight and into late morning hours Sunday before gradually weakening mid- late afternoon Sunday. Winds will then become light from the west Sunday night.

Extended Aviation Outlook: A cold front may bring flight restrictions Wednesday, mainly due to rain showers.

MARINE

Through Tonight: Solid gales are being observed across all waters this morning and a Gale Warning remains in place. Conditions will improve below gales after daybreak in the Charleston Harbor, late morning for the all nearshore waters and early afternoon for the Georgia offshore waters. Small Craft Advisories will likely be needed once the Gale Warnings are lowered.

Monday Night through Thursday: Surface High pressure will be over FL on Tuesday, shifting offshore Tuesday night into Wednesday. A cold front will approach from the west on Wednesday, quickly moving through and then offshore Wednesday night. High pressure builds in from the distant west on Thursday. Small Craft Advisories will be needed for portions of our waters Wednesday night into Thursday.

CLIMATE

Record Low Temperatures:

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:

February 1: KCHS: 38/1980 KCXM: 36/1900 KSAV: 38/1900

February 2: KCHS: 38/1980 KCXM: 38/1898 KSAV: 38/1951

Record Snowfall:

0.7" of snow was observed at KCHS for 01/31. This breaks the previous record of 0.6" set in 1977.

February 1: KCHS: no record established KSAV: no record established

EQUIPMENT

The KCLX radar is operational, but could go down at any time. Additional repairs are needed.

CHS WATCHES/WARNINGS/ADVISORIES

GA...Winter Storm Warning until 1 PM EST this afternoon for GAZ087- 088-099>101. Extreme Cold Warning until 1 PM EST this afternoon for GAZ087- 088-099>101-114>119-137>141. Cold Weather Advisory from 6 PM this evening to 9 AM EST Monday for GAZ087-088-099>101-114>119-137>141. Winter Weather Advisory until 10 AM EST this morning for GAZ115>119. SC...Winter Storm Warning until 1 PM EST this afternoon for SCZ040- 042>045-047>052. Extreme Cold Warning until 1 PM EST this afternoon for SCZ040- 042>045-047>052. Cold Weather Advisory from 6 PM this evening to 9 AM EST Monday for SCZ040-042>045-047>052. Lake Wind Advisory until 10 AM EST this morning for SCZ045. MARINE...Gale Warning until 7 AM EST this morning for AMZ330. Gale Warning until 10 AM EST this morning for AMZ350-352-354. Gale Warning until 1 PM EST this afternoon for AMZ374.