GOVERNOR BOB MCDONNELL HAS DECLARED THE WEEK DECEMBER 5 TO 11, 2010 AS WINTER PREPAREDNESS WEEK IN VIRGINIA. THE NATIONAL WEATHER SERVICE OFFICES SERVING VIRGINIA...IN COOPERATION WITH THE VIRGINIA DEPARTMENT OF EMERGENCY MANAGEMENT...WILL SEND PUBLIC INFORMATION STATEMENTS EACH DAY THROUGH SATURDAY AT APPROXIMATELY 11 AM. THESE STATEMENTS WILL FOCUS ON DIFFERENT ASPECTS OF WINTER WEATHER ...AND PREPAREDNESS ACTIONS THE PUBLIC SHOULD TAKE FOR THE UPCOMING WINTER SEASON. ...WINTER FORECAST NOT AS COLD AND SNOWY AS LAST WINTER... THE WINTER OF 2009-10 WILL LONG BE REMEMBERED FOR ITS PERSISTENT COLD AND RECORD SNOWFALLS ACROSS MANY PORTIONS OF THE MID ATLANTIC REGION. THE WINTER STARTED EARLY...WITH A RECORD SNOWSTORM ON DECEMBER 18TH AND 19TH...WITH SIGNIFICANT SNOWFALLS OCCURRING WELL INTO FEBRUARY 2010. IN SOME PARTS OF VIRGINIA...SNOW WAS ON THE GROUND CONTINUOUSLY FOR MORE THAN 2 MONTHS. THIS WINTER...OCEAN TEMPERATURES IN THE EQUATORIAL PACIFIC OCEAN ARE FORECAST TO REMAIN NORMAL...OR IN A LA NINA PATTERN. LA NINA WINTERS ARE GENERALLY CHARACTERIZED BY DRIER THAN NORMAL CONDITIONS ACROSS THE EASTERN SEABOARD. THIS IS DUE TO THE FACT THAT THE PRIMARY STORM TRACK DURING LA NINA WINTERS IS ALONG OR WEST OF THE APPALACHIAN MOUNTAINS. THIS PATTERN ALSO GENERALLY PRODUCES WARMER THAN AVERAGE WINTER TEMPERATURES. HOWEVER...ATMOSPHERIC PATTERNS SUCH AS THE NORTH ATLANTIC OSCILLATION ...N.A.O. AND THE PACIFIC-NORTH AMERICA INDEX...WHICH AFFECT THE AMOUNT OF COLD AIR AVAILABLE AND THE MOVEMENT OF COASTAL WEATHER SYSTEMS...ARE NOT PREDICTABLE MORE THAN 2-3 WEEKS IN ADVANCE. LAST WINTER...THE NAO WAS GENERALLY NEGATIVELY...LEADING TO A COLDER THAN AVERAGE WINTER. SINCE THE NAO HAS TENDED TO REMAIN NEGATIVE MOST OF 2010...IT IS QUITE POSSIBLE A NEGATIVE NAO COULD PRODUCE COLDER TEMPERATURES THAN WOULD NORMALLY BE EXPECTED IN A LA NINA WINTER. THE NATIONAL WEATHER SERVICE OUTLOOK FOR THE 2009-10 WINTER INDICATES NEAR NORMAL TEMPERATURES EAST OF THE BLUE RIDGE...AND ABOVE NORMAL TEMPERATURES WEST OF THE BLUE RIDGE. IN GENERAL...NEAR NORMAL PRECIPITATION IS ANTICIPATED. ALTHOUGH THE OVERALL FORECAST MAY NOT BE WORRISOME IN COMPARISON TO LAST WINTER...PREPARATION FOR POTENTIAL WINTER STORMS IS A MUST. EVERYONE SHOULD BE PREPARED FOR OCCASIONAL COLD SNAPS AND THE POSSIBILITY OF AT LEAST ONE SIGNIFICANT WINTER STORM THIS COMING WINTER. IN ADDITION...IT HAS BEEN NEARLY A DECADE SINCE VIRGINIA EXPERIENCED A SIGNIFICANT ICE STORM. IT IS ONLY A MATTER OF TIME BEFORE THE COMMONWEALTH EXPERIENCES AN ICE EVENT LIKE THOSE SEEN IN 1994...1998 AND 1999. HERE IS A LINK TO THE NOAA WINTER OUTLOOK FOR 2010-11. HTTP://WWW.NOAANEWS.NOAA.GOV/STORIES2010/20101021_WINTEROUTLOOK.HTML BELOW ARE SOME DEFINITIONS OF VARIOUS WINTER PRECIPITATION TYPES...AS WELL AS INFORMATION ON NWS WINTER STORM WARNINGS AND ADVISORIES AS THEY APPLY TO VIRGINIA. ....WINTER PRECIPITATION TERMS.... ....FREEZING RAIN.... FREEZING RAIN IS RAIN THAT FALLS AND FREEZES TO A COLD SURFACE SUCH AS A ROAD OR TREE...CAUSING A GLAZE OF ICE TO FORM. FREEZING RAIN FORMS WHEN SNOW FALLS THROUGH A WARM LAYER ABOVE THE GROUND...MELTS TO RAIN...THEN RE-FREEZES UPON REACHING THE GROUND...WHERE THE AIR AND GROUND-LEVEL OBJECTS ARE BELOW FREEZING. FREEZING RAIN OR "ICE STORMS" CAN ALSO KNOCK DOWN TREES AND POWER LINES...AND SEVERELY HAMPER TRAVEL. THE ICE STORM IN FEBRUARY 1994 LEFT SOME AREAS OF VIRGINIA WITHOUT POWER FOR A WEEK. ....SLEET.... SLEET IS RAIN THAT HAS RE-FROZEN INTO ICE PELLETS PRIOR TO REACHING THE GROUND. SLEET FORMS IN A SIMILAR MANNER TO FREEZING RAIN. HOWEVER...THE LAYER OF COLD AIR NEAR THE GROUND IS THICK ENOUGH TO ALLOW THE RAIN DROPS TO RE-FREEZE BEFORE REACHING THE GROUND. SLEET WILL BOUNCE WHEN IT STRIKES A HARD SURFACE. SLEET CAN ACCUMULATE LIKE SNOW AND MAKE A ROAD SLICK...BUT IT IS NOT AS HAZARDOUS AS FREEZING RAIN. ....BLIZZARD... A BLIZZARD OCCURS WHEN WINDS 35 MPH OR GREATER COMBINE WITH FALLING OR BLOWING SNOW TO REDUCE VISIBILITY TO OR BELOW ONE QUARTER MILE FOR 3 HOURS OR MORE CAUSING WHITE-OUT CONDITIONS. WIND CHILL TEMPERATURES ARE OFTEN NEAR OR BELOW ZERO IN A BLIZZARD. PEOPLE OUT IN BLIZZARDS CAN QUICKLY BECOME DISORIENTED FROM THE COLD...SNOW AND WIND...AND LOSE THEIR WAY WHEN ONLY SEVERAL YARDS FROM THEIR HOME OR CAR. ....FLURRIES.... THE TERM FLURRIES REFERS TO VERY LIGHT SNOW OR SNOW THAT OCCURS FOR A SHORT TIME PERIOD ONLY CAUSING A LIGHT DUSTING AT BEST. ....WIND CHILL.... WIND CHILL TEMPERATURE IS THE "FEEL-LIKE" TEMPERATURE DENOTING THE COMBINED EFFECT OF WIND AND TEMPERATURE ON PEOPLE AND ANIMALS. WIND CHILL IS BASED ON THE RATE OF HEAT LOSS FROM EXPOSED SKIN. WEARING LAYERS OF CLOTHING WILL HELP RETAIN YOUR BODY HEAT AND COMBAT WIND CHILL. ONCE WIND CHILL TEMPERATURES DROP BELOW -20 DEGREES...EXPOSED FLESH CAN FREEZE IN 30 MINUTES OR LESS...CAUSING FROST BITE. ...WINTER WEATHER WARNINGS AND ADVISORIES - WHAT DO THEY MEAN?... FORECASTS FOR WINTER WEATHER ISSUED BY THE NATIONAL WEATHER SERVICE OFTEN INCLUDE WATCHES...WARNINGS AND ADVISORIES DESIGNED TO INFORM THE PUBLIC OF THE POTENTIAL SEVERITY OF A GIVEN WEATHER SITUATION. UNDERSTANDING THESE MESSAGES CAN GUIDE YOU TO MAKING THE PROPER PREPARATIONS FOR AN UPCOMING WEATHER EVENT. HERE IS A LIST OF SOME OF THE ADVISORIES...WATCHES AND WARNINGS ISSUED BY THE NATIONAL WEATHER SERVICE...AND WHAT THEY MEAN IN TERMS OF EXPECTED WEATHER CONDITIONS. ......WATCHES AND WARNINGS...... WATCHES AND WARNINGS ARE ISSUED BY THE NATIONAL WEATHER SERVICE FOR POTENTIALLY LIFE-THREATENING CONDITIONS REGARDLESS OF THE TIME OF YEAR. IN WINTER...WATCHES AND WARNINGS ARE MOST OFTEN ISSUED FOR SIGNIFICANT SNOW AND/OR ICE STORMS...BUT MAY BE ISSUED FOR EXTREMELY COLD WIND CHILL TEMPERATURES...FLOODING AND POSSIBLY EVEN SEVERE THUNDERSTORMS. BELOW ARE A LIST OF WINTER WEATHER WATCHES AND WARNINGS. WINTER STORM WATCH...ISSUED WHEN THE FOLLOWING WEATHER CONDITIONS ARE POSSIBLE WITHIN 24 TO 48 HOURS - AT LEAST 3 TO 6 INCHES OF SNOW AND/OR ICE ACCUMULATIONS OF 1/4 INCH OR MORE...IN A 12 TO 24 HOUR PERIOD. WINTER STORM WARNING... ISSUED WHEN THE WATCH CONDITIONS DESCRIBED ABOVE ARE EITHER IMMINENT OR LIKELY WITHIN 24 HOURS. BLIZZARD WARNING...ISSUED WHEN STRONG WINDS COMBINE WITH FALLING AND/OR BLOWING SNOW TO REDUCE VISIBILITY TO ONE QUARTER MILE OR LESS FOR AT LEAST 3 HOURS. DEEP SNOW DRIFTS AND DANGEROUSLY LOW WIND CHILLS OFTEN ACCOMPANY BLIZZARD CONDITIONS. WIND CHILL WARNING...ISSUED WHEN WIND CHILL TEMPERATURES (THE COMBINED EFFECT OF WIND AND TEMPERATURE ON EXPOSED SKIN) ARE FORECAST TO REACH 20 DEGREES BELOW ZERO OR COLDER. ......ADVISORIES...... WEATHER ADVISORIES ARE ISSUED FOR HAZARDOUS...BUT NOT NECESSARILY LIFE-THREATENING CONDITIONS FREEZING RAIN/FREEZING DRIZZLE ADVISORY...ISSUED WHEN FREEZING RAIN OR FREEZING DRIZZLE WILL PRODUCE HAZARDOUS CONDITIONS FOR MOTORISTS AND PEDESTRIANS. WIND CHILL ADVISORY...ISSUED WHEN WIND CHILL TEMPERATURES...THE APPARENT TEMPERATURE RESULTING FROM THE COMBINATION OF WIND AND COLD TEMPERATURES...RANGE BETWEEN 5 DEGREES BELOW ZERO AND 19 DEGREES BELOW ZERO. ALTHOUGH WIND CHILL VALUES IN THIS RANGE ARE ONLY LIFE THREATENING WHEN SKIN IS EXPOSED FOR MORE THAN ONE HOUR...NOT TAKING NECESSARY PRECAUTIONS TO PROTECT ONE FROM THE COLD COULD RESULT IN HYPOTHERMIA. WINTER WEATHER ADVISORY...ISSUED WHEN A COMBINATION OF SNOW...SLEET OR FREEZING RAIN PRECIPITATION WILL CAUSE SIGNIFICANT INCONVENIENCE AND HAZARDOUS DRIVING CONDITIONS. WINTER STORMS ARE DECEPTIVE KILLERS BECAUSE MOST DEATHS ARE INDIRECTLY RELATED TO THE STORM. EXAMPLES ARE TRAFFIC ACCIDENTS DUE TO ICY ROADS...HEART ATTACKS WHILE SHOVELING SNOW...OR DEATHS DUE TO PROLONGED EXPOSURE TO THE COLD. THE ADVISORIES...WATCHES AND WARNINGS LISTED ABOVE ARE ISSUED TO HELP YOU...THE PUBLIC... PREPARE FOR UPCOMING WINTER WEATHER AND TAKE APPROPRIATE ACTION TO PROTECT YOURSELF AND YOUR PROPERTY. WHATEVER WEATHER THIS WINTER BRINGS...THE VIRGINIA DEPARTMENT OF EMERGENCY MANAGEMENT...AND THE NATIONAL WEATHER SERVICE WANT YOU TO BE PREPARED FOR THE SEASON AHEAD. THE STATEMENTS WHICH WILL BE SENT THIS WEEK ARE DESIGNED TO ASSIST IN THAT PREPARATION. BEING PREPARED MEANS HAVING THE NECESSARY INFORMATION TO MAKE THE RIGHT DECISIONS. WEATHER FORECASTS PLAY A LARGE ROLE IN THIS DECISION MAKING PROCESS. THE NATIONAL WEATHER SERVICE RECOMMENDS THAT YOU REGULARLY TUNE TO NOAA WEATHER RADIO OR YOUR LOCAL RADIO AND TELEVISION STATIONS TO STAY ABREAST OF WEATHER CONDITIONS THIS WINTER. ADDITIONAL INFORMATION ON WINTER WEATHER PREPAREDNESS CAN BE OBTAINED ON-LINE THROUGH THE VIRGINIA DEPARTMENT OF EMERGENCY MANAGEMENT HOME PAGE AT: WWW.VAEMERGENCY.COM/THREATS/WINTER/INDEX.CFM IN ADDITION...THE READY VIRGINIA WEB SITE HAS BEEN DEVELOPED TO AID VIRGINIANS IN THEIR OVERALL DISASTER PREPAREDNESS: WWW.READYVIRGINIA.GOV...ENGLISH VERSION/ WWW.LISTOVIRGINIA.GOV...SPANISH VERSION/ UP-TO-DATE WEATHER INFORMATION IS ALSO AVAILABLE ON-LINE FROM THE NATIONAL WEATHER SERVICE AT: WWW.WEATHER.GOV/BLACKSBURG. THE NATIONAL WEATHER SERVICE WINTER WEATHER AWARENESS HOME PAGE IS: WWW.NWS.NOAA.GOV/OM/WINTER/INDEX.SHTML