BOF 000 FXUS61 KBTV 241959 AFDBTV AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE BURLINGTON VT 259 PM EST TUE NOV 24 2009 .SYNOPSIS... A WEAK AREA OF HIGH PRESSURE WILL BE OVER THE NORTH COUNTRY TONIGHT INTO WEDNESDAY MORNING. A FRONTAL SYSTEM WILL THEN BRING A CHANCE OF SHOWERS TO THE REGION WEDNESDAY AFTERNOON INTO WEDNESDAY NIGHT. HIGH PRESSURE THEN RETURNS FOR THANKSGIVING DAY...FOLLOWED BY A STORM SYSTEM FOR FRIDAY INTO SATURDAY. && .NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/... AS OF 237 PM EST TUESDAY...MUCH OF FORECAST AREA ENJOYED SOME CLEARING THIS AFTERNOON AS SHRTWV TROUGH HAS EXITED REGION AND WEAK HIGH PRESSURE DEVELOPS OVER THE AREA. THIS HIGH WILL REMAIN OVER THE REGION TONIGHT...BUT MODELS INDICATING SOME MSTR IN LOW AND MID LEVELS...SO EXPECTING SKIES TO BALANCE OUT PARTLY CLOUDY. ALSO EXPECT DEVELOPMENT OF SOME PATCHY FOG OVERNIGHT. HAVE GONE WITH A BLEND OF MAV/MET TEMPS...RESULTING IN LOWS RANGING FROM MID 20S TO MID 30S ACROSS THE AREA. && .SHORT TERM /6 AM WEDNESDAY MORNING THROUGH THURSDAY NIGHT/... AS OF 237 PM EST TUESDAY...RIDGE MOVES EAST OF FORECAST AREA DURING WEDNESDAY...AS UPPER TROUGH AND ITS ASSOCD SFC LOW DEVELOP OVER GRTLKS REGION AND MOVE ENE. SLOW DEPARTURE AND BREAKDOWN OF RIDGE WILL RESULT IN BULK OF PCPN ASSOCD WITH THE TROUGH REMAINING OVER NRN NY DURING WEDNESDAY AFTERNOON. BETTER CHC OF SHWRS ACRS ENTIRE FORECAST WEDNESDAY EVENING AS SHRTWV MOVES ACRS THE RGN. BROAD SSW FLOW OVER THE AREA ON THANKSGIVING DAY. WEAK RIDGING DEVELOPS IN ADVANCE OF LARGE DEEPENING CLOSED LOW OVER THE MIDWEST. AT THIS TIME...IT APPEARS AS IF BULK OF THANKSGIVING DAY WILL BE DRY...ALTHOUGH THERE WILL BE AN INCR IN CLOUDS DURING THE PM. AS CLOSED LOW MAKES ITS WAY EASTWARD THURSDAY NIGHT...SFC LOW WILL TAKE SHAPE OFF MID ATLC COAST. DIFFERENCES IN MODELS AS TO WHERE AND WHEN THIS DEVELOPMENT WILL OCCUR. HOWEVER...WITH GOOD UPPER LEVEL FORCING AND JET DYANMICS COMBINED WITH ADVECTION OF DEEP MSTR INTO THE RGN...EXPECT SHWRS TO DEVELOP OVRNGHT...WITH CHC THAT RAIN MAY MIX WITH SNOW OVER ADRNDKS LATE THURS NITE AS AIRMASS BEGINS TO COOL WITH APRCH OF UPPER LOW. && .LONG TERM /FRIDAY THROUGH MONDAY/... AS OF 300 PM EST TUESDAY...VERY ACTIVE EXTENDED PORTION OF THE FORECAST TODAY. STILL MANY QUESTIONS ABOUT THE SYSTEM TO AFFECT THE REGION FRIDAY. SURFACE LOW OFF THE COAST OF NEW ENGLAND ON FRIDAY MORNING WILL TRACK NORTHEAST. LOW BECOMES SOMEWHAT DOUBLE- BARRELED ON FRIDAY...WITH STRONGEST PART OF THE SURFACE LOW REMAINING OUTSIDE THE BENCHMARK. A SECOND WEAKER LOW WILL REMAIN CLOSER TO UPPER LOW WHICH WILL TRACK FROM PA EAST OFF THE COAST OF NJ ON FRIDAY EVENING. REGION WILL HAVE COLD AIR ALOFT...BUT STILL HAVE MAX TEMPS ON FRIDAY IN THE LOWER TO MID 40S. THEREFORE LOOKING AT MOSTLY RAIN FOR FRIDAY. ON FRIDAY NIGHT SURFACE LOW AND UPPER LEVEL LOW WILL TRACK NORTHEAST TOWARDS NOVA SCOTIA. MORE COLD AIR MOVES INTO THE REGION WITH CAA FOLLOWING DEPARTING SYSTEM...AND REMAINING WRAP AROUND PRECIPITATION SHOULD BE MOSTLY SNOW OVER NIGHT IN THE HIGHER ELEVATIONS...WITH A MIX OF RAIN AND SNOW IN THE VALLEYS. SOME WRAP AROUND SNOW SHOWERS WILL CONTINUE SATURDAY IN THE HIGHER ELEVATIONS IN NORTHWEST FLOW...UPPER LEVEL RIDGE BUILDS OVER THE REGION AND SURFACE HIGH PRESSURE WILL TRY TO RIDGE INTO THE AREA FROM THE SOUTHEAST ON SATURDAY NIGHT AND INTO SUNDAY. SATURDAY NIGHT AND SUNDAY WILL REMAIN DRY. ANOTHER LOW PRESSURE SYSTEM WILL DEVELOP AND DEEPEN OVER THE GREAT LAKES REGION ON SUNDAY NIGHT. MEANWHILE...YET ANOTHER POTENT LOW PRESSURE SYSTEM IS SHAPING UP OVER THE GULF COAST REGION OF MS...AL...GA. THIS LOW WILL SYNCH WITH LOW OVER THE GREAT LAKES REGION ON MONDAY...THEN TRACK EAST. UPPER LEVEL TROF WILL COINCIDE WITH THIS FEATURE...INCREASING POTENTIAL FOR A SIGNIFICANT SYSTEM TO AFFECT THE EAST COAST EARLY NEXT WEEK. SOUTHERN STREAM LOW WILL END UP BEING THE STRONGER OF THE TWO SURFACE LOWS...AND WILL TRACK NORTHEAST AND ACROSS OUR FORECAST AREA ON TUESDAY. THIS SYSTEM WILL HAVE DEEP MOISTURE...SINCE IT ORIGINATES CLOSE TO THE GULF. IT WILL ALSO HAVE WARM AIR ASSOCIATED WITH IT BECAUSE OF WHERE IT FORMED. AS THIS LOW CROSSES OUR FORECAST AREA ON TUESDAY RAIN IS EXPECTED. ALTHOUGH...THIS SYSTEM IS STILL SO FAR OUT IN THE FORECAST THAT THERE IS LOTS OF UNCERTAINTY. AS WE GET CLOSER TO EARLY NEXT WEEK...THE DETAILS WILL BECOME MORE CLEAR. && .AVIATION /18Z TUESDAY THROUGH SUNDAY/... THROUGH 18Z WEDNESDAY...CONDITIONS BECMG VFR 18Z THROUGH 00-03Z...THEN AREAS OF LIFR IN FOG FORMING WITH LIGHT WINDS UNDER A NEARLY STATIONARY AREA OF WEAK HIGH PRESSURE. FOG EXPECTED TO FORM TONIGHT THOUGH EXACTLY WHEN AND WHERE A BIT UNCERTAIN. LOW LEVEL MOISTURE CONTINUES HIGH WITH DEWPOINTS RUNNING IN THE UPPER 30S TO LOWER 40S. SO WHEN TEMPS FALL AND REACH THOSE READINGS BETWEEN 02-06Z THATS WHEN FOG SHOULD FORM. SOME LOW TO MID CLOUDS ACROSS NY COULD PUT A CAP ON THE FOG FORMATION BUT RIGHT NOW DON'T THINK THAT WILL CURTAIN FOG FORMATION. IN FACT AT BTV...NAM MOS INDICATES LIFR POSSIBLE 12Z WED BUT NOT SURE ENOUGH TO INCLUDE AT BTV JUST YET. WEAK RIDGE OF HIGH PRESSURE WILL GIVE WAY SLOWLY ON WEDNESDAY TO A WEAK SRLY WIND AHEAD OF LOW PRESSURE MOVING IN THE GREAT LAKES REGION. MORNING FOG AND STRATUS WILL GIVE WAY TO SOME MID CLOUDS BY 18Z. OUTLOOK 18Z WEDNESDAY THROUGH SUNDAY... 18Z WEDNESDAY THROUGH THURSDAY...GENERALLY VFR. SCT MVFR -SHRA KMSS. FRIDAY...MVFR WITH SCATTERED IFR IN DEVELOPING RAIN. FRIDAY NIGHT...IFR IN RA CHANGING TO SN...ESP MTNS. SATURDAY...IFR IN SN HIR ELEVATIONS. RASN ELSESHWERE. GUSTY NW WINDS. SUNDAY...BECMG VFR. GUSTY NW WINDS DIMINISHING. && .CLIMATE... AS OF 1235 PM MONDAY...ALTHOUGH MOST OF THE NORTH COUNTRY SAW A LIGHT COATING OF SNOW BACK IN MID OCTOBER...THE IMMEDIATE CHAMPLAIN VALLEY HAS NOT YET HAD ITS FIRST MEASURABLE SNOW EVENT OF THE SEASON. FOR BURLINGTON...ON AVERAGE THE FIRST MEASURABLE SNOW HAPPENS NOVEMBER 6TH. SO WHERE DOES THIS LATE 1ST MEASURABLE SNOW COMPARE TO THE RECORD BOOKS? HERE ARE THE 10 LATEST FIRST SNOWS FOR BURLINGTON GOING BACK TO 1906...ALONG WITH THE SEASONAL TOTAL SNOW THAT FOLLOWED. SEASON TOTAL RANK DATE SNOWFALL (INCHES) 1. 12/7/1937 45.1 2. 12/5/1915 54.4 3. 12/1/1948 40.7 4. 11/30/1918 69.6 11/30/1953 83.6 11/30/1960 51.6 7. 11/28/1913 56.5 8. 11/27/1941 57.7 9. 11/26/1982 80.5 10. 11/25/1957 94.9 && .BTV WATCHES/WARNINGS/ADVISORIES... VT...NONE. NY...NONE. && $$ SYNOPSIS...RJS NEAR TERM...RJS SHORT TERM...RJS LONG TERM...NEILES AVIATION...SISSON CLIMATE...NASH EOF