NOUS42 KCHS 041100 PNSCHS GAZ087-088-099>101-114>119-137>141-SCZ040-042>045-047>052-051100- PUBLIC INFORMATION STATEMENT NATIONAL WEATHER SERVICE CHARLESTON SC 600 AM EST TUE DEC 4 2012 ...WINTER WEATHER AWARENESS WEEK CONTINUES ACROSS SOUTH CAROLINA AND GEORGIA... TODAY WE WILL DISCUSS THE IMPACTS OF SNOW AND SLEET ACROSS SOUTHEAST GEORGIA AND SOUTHEAST SOUTH CAROLINA. OUR REGION AVERAGES LESS THAN ONE INCH OF SNOWFALL PER YEAR. THE PROBABILITY FOR SNOW AND SLEET DURING ANY GIVEN WINTER RANGES FROM LESS THAN 10 TO 15 PERCENT ACROSS COASTAL COUNTIES AND COUNTIES ALONG AND SOUTH OF INTERSTATE 16...TO 15 TO 25 PERCENT FARTHER NORTH AND ACROSS INLAND LOCATIONS. SNOW AND SLEET ARE RARE AT OUR LATITUDE BECAUSE NECESSARY INGREDIENTS SUCH AS MOISTURE AND COLD AIR SELDOM DEVELOP OR ARRIVE HERE AT THE SAME TIME. HOWEVER...DURING RARE OCCASIONS WHEN THESE FACTORS COMBINE...WE CAN EXPERIENCE SIGNIFICANT SNOWSTORMS. SNOW BURIED PARTS OF THE REGION IN FEBRUARY 1973...DECEMBER 1989 AND MOST RECENTLY IN FEBRUARY 2010. SNOW WILL ACCUMULATE MOST READILY ON BRIDGES...OVERPASSES AND ON NON-PAVED SURFACES SUCH AS TREES...AUTOMOBILES AND WOODEN DECKS. SINCE THE GROUND TEMPERATURE NORMALLY REMAINS ABOVE FREEZING IN OUR REGION...AND SINCE THE SUN CAN WARM THE GROUND AND THE ATMOSPHERE EVEN ON CLOUDY DAYS...MOST LIGHT SNOW WILL TEND TO MELT AT TEMPERATURES CLOSE TO FREEZING. HOWEVER...HEAVY SNOW WILL ACCUMULATE ANYWHERE AND CAN QUICKLY CREATE DANGEROUS TRAVEL CONDITIONS. FURTHER...EVEN A FEW INCHES OF HEAVY WET SNOW CAN BRING DOWN TREES...TREE LIMBS AND POWER LINES. IN OUR REGION...INFREQUENT SNOW EVENTS USUALLY OCCUR AT TEMPERATURES CLOSE TO FREEZING...AND SNOW WILL NORMALLY MELT FAIRLY QUICKLY AFTER PRECIPITATION ENDS ESPECIALLY DURING THE DAY. HOWEVER...IF TEMPERATURES ARE EXCEPTIONALLY COLD SNOW WILL ACCUMULATE MORE EFFICIENTLY ON MORE SURFACES AND WILL MELT VERY SLOWLY EVEN AFTER PRECIPITATION ENDS. THIS WAS THE CASE DURING THE SNOWSTORM OF DECEMBER 23 1989...WHEN FRIGID TEMPERATURES TOPPED OUT AT 20 DEGREES IN CHARLESTON AND 22 DEGREES IN SAVANNAH. SLEET COMMONLY FORMS WHEN SNOW PARTIALLY MELTS AS IT FALLS THROUGH WARM AIR ALOFT. WHILE SLEET WILL TYPICALLY ACCUMULATE LESS RAPIDLY THAN SNOW AND CAN REDUCE TOTAL SNOW ACCUMULATION DURING A GIVEN STORM...HEAVY SLEET CAN STILL PRODUCE HAZARDOUS TRAVEL CONDITIONS. THE NATIONAL WEATHER SERVICE IN CHARLESTON SOUTH CAROLINA WILL ISSUE A WINTER STORM WARNING FOR HEAVY SNOW AND/OR SLEET WHEN WE EXPECT AT LEAST 2.0 INCHES OF ACCUMULATION WITHIN A 12 HOUR PERIOD...OR WHEN LESSER AMOUNTS OF SNOW AND SLEET WILL ACCUMULATE QUICKLY AND WILL PRODUCE TRAVEL CONDITIONS WHICH ENDANGER LIVES. YOUR RESPONSE TO OUR OUTLOOKS...WATCHES...WARNINGS AND ADVISORIES CAN DICTATE THE SUCCESS OF OUR SERVICES. FRIDAY...WE WILL BRIEFLY DISCUSS WINTER WEATHER PREPAREDNESS PLANS. CHECK OUT ADDITIONAL WINTER WEATHER AWARENESS WEEK INFORMATION ON OUR WEB PAGE AT WWW/ERH.NOAA.GOV/CHS/...AS WELL ON FACEBOOK AT WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHARLESTONSC.GOV. YOU CAN ALSO FOLLOW @NWSCHARLESTONSC ON TWITTER. $$