Here comes Hurricane Sandy, the Frankenstorm! Part V
000 FXUS61 KCAR 291932 AFDCAR AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE CARIBOU ME 332 PM EDT MON OCT 29 2012 .SYNOPSIS... SANDY WILL CONTINUE TO MOVE NORTHWESTWARD ACROSS THE SOUTHEAST NEW JERSEY COAST THIS EVENING AND INTO SOUTHERN PENNSYLVANIA LATE TONIGHT. SANDY IS EXPECTED TO WEAKEN AND CONTINUE TO AFFECT OUR REGION WITH SIGNIFICANT RAIN AND BREEZY WINDS INTO WEDNESDAY AND THEN INTERMITTENT SHOWERS INTO THE LATE WEEK. && .NEAR TERM /THROUGH TUESDAY/... THE CONCERN FOR THE NEAR TERM CONTINUES TO BE HIGH WINDS THIS EVENING AND OVERNIGHT AND HEAVY RAINFALL TONIGHT AND TOMORROW. ALL HEADLINES REMAIN IN PLACE WITH NO CHANGES NEEDED WITH THIS FORECAST PACKAGE. FOR THIS EVENING AND OVERNIGHT....SANDY IS POISED TO MAKE LANDFALL IN NEW JERSEY THIS EVENING...AND WILL THEN WEAKEN AS IT MOVES INLAND. THE WIND FIELD OF THIS STORM IS ALREADY WIDENING, AND IT WILL CONTINUE TO DO SO OVERNIGHT TONIGHT. THEREFORE, WINDS WILL CONTINUE TO INCREASE ACROSS THE FORECAST AREA THIS EVENING, PEAKING BETWEEN 8 PM AND MIDNIGHT. THE STRONGEST WINDS WILL BE ACROSS DOWNEAST MAINE, WHERE GUSTS OF 55 TO 60 MPH ARE EXPECTED. WIND INTENSITY WILL DECREASE AS YOU MOVE NORTH, WITH GUSTS OF 45 TO 50 MPH OVER THE HIGHER TERRAIN OF CENTRAL MAINE. MOST OF AROOSTOOK WILL STAY AT OR BELOW 40 MPH FOR GUSTS. THE WINDS SHOULD GRADUALLY SUBSIDE AFTER MIDNIGHT AS THE PRESSURE GRADIENT STARTS TO LESSEN. GIVEN THAT THE FORECAST MODELS INITIATED WITH PRESSURE TOO LOW IN THE STORM`S CENTER THIS MORNING, HAVE KEPT THE WINDS UP A BIT LONGER THAN GUIDANCE IS CURRENTLY INDICATING. RAIN WILL BEGIN TO MOVE INTO SOUTHWESTERN PORTIONS OF THE FORECAST AREA 8-10 PM AND THEN SPREAD NORTHEAST THROUGH THE NIGHT. WITH EAST TO EAST SOUTHEAST WINDS EXPECTED, THE AREA OF MAIN CONCERN WILL BE THE UPSLOPE REGIONS. SEE THE HYDRO SECTION BELOW FOR MORE DETAILS ON THE RAIN AND FLOODING SITUATION. FOR TUESDAY...RAIN CONTINUES OVER THE FORECAST AREA RIGHT THROUGH THE DAY. HOWEVER, IT WILL BE A MILD DAY AS WE STAY IN THE MARITIME AIR ON THE EAST SIDE OF SANDY`S REMNANTS. BREEZY CONDITIONS CAN BE EXPECTED BUT NOT NEARLY AS DRAMATIC AS MONDAY NIGHT. STILL GUSTS OF 30 TO 40 MPH WILL BE POSSIBLE, ESPECIALLY DOWNEAST AND ALONG THE COAST. BOTH THE LATEST NAM AND GFS INDICATE THERE WILL BE ELEVATED INSTABILITY (200-450 J/KG CAPE) PRESENT OVER MUCH OF THE FORECAST AREA SO HAVE CONTINUED WITH A CHANCE OF THUNDER FOR TOMORROW AFTERNOON. && .SHORT TERM /TUESDAY NIGHT THROUGH THURSDAY/... MOST MODELS INDICATE WHATS LEFT OF THE HIGH PRECIPITABLE WATER TROP STREAM (UP TO 1.50 IN) OF SANDY FROM THE SUB-TROP WRN ATLC WILL STILL BE IMPACTING THE FA TUE NGT INTO WED MORN WERE WE STILL INDICATE ORGANIZED RNFL ALG AND AHEAD A WEAK OCCLUDED/COLD FRONT ACROSS SPCLY ERN AND SRN PTNS OF THE REGION. RNFL SHOULD THEN DIMINISH TO SHWRS WSW TO ENE ACROSS THE FA WED AFTN INTO WED NGT AS DRY SLOT CONDITIONS MOVE INTO THE FA FROM QB PROV. DUE TO HOW FAR NW THE UPPER LOW MIGRATES (NW PA)...IT WILL TAKE TO LATE THU FOR ADDITIONAL ORGANIZED SHWR RNFL TO MOVE BACK INTO THE FA WITH THE EVENTUAL APCH UPPER LOW. TEMPS TUE NGT THRU WED NGT WILL CONT WELL ABV NORMAL...SPCLY AT NGT WITH LITTLE DIURNAL RANGE DUE TO CLD CVR AND RNFL. HI TEMPS THU SHOULD BE AT LEAST 5 DEG F COOLER BEHIND THE OCCLUDED/COLD FRONT && .LONG TERM /THURSDAY NIGHT THROUGH MONDAY/... THE MODEL GUIDANCE IS IN GOOD AGREEMENT AT THE START OF THE LONG TERM. A COMPLEXED LOW PRESSURE SYSTEM WILL BE OVER ALL OF NORTHERN NEW ENGLAND AND EASTERN CANADA AT THE START OF THE PERIOD. THOUGH NOT EXACTLY THE SAME THE GFS...ECMWF...NAM80 ARE IN GOOD AGREEMENT. THAT THERE WILL BE MULTIPLE LOW PRESSURE CENTER ASSOCIATED WITH THIS SYSTEM. A CANADIAN HIGH PRESSURE SYSTEM WILL BEGIN TO BUILD SOUTH INTO THE MID-WEST. A NEW LOW OVR COLORADO. THESE SYSTEMS WILL SLOWLY DRIFT EAST THROUGH THE EARLY PORTIONS OF THE PERIOD. BY SUNDAY EVENING THE LOW PRESSURE AREA WILL MOVE EAST INTO THE CANADIAN MARITIMES...THE HIGH PRESSURE RIDGE BEGINS TO BUILD INTO WESTERN MAINE BRINGING MUCH COOLER AIR INTO THE AREA. THE NEW LOW PRESSURE WILL CONTINUE TO DEVELOP AND BY THIS TIME BE CENTERED IN THE CHICAGO AREA WITH A COLD FRONT EXTENDING SW INTO CENTRAL TEXAS. THE HIGH PRESSURE RIDGE WILL DOMINATE THE WEATHER THROUGH MONDAY EVENING ACCORDING TO BOTH THE GFS AND ECMWF. BETWEEN SUNDAY EVENING AND THE END OF THE PERIOD MONDAY MORNING THE MODELS DIVERGE ON THEIR SOLUTION. THE GFS BRINGS THE LOW PREVIOUSLY OVER THE CHICAGO AREA VERMONT...WITH A WARM FRONT EXTENDING EAST INTO MAINE. THE ECMWF MOVES THIS LOW SE TO COASTAL VIRGINA. LOADED A BLEND OF GFS AND ECMWF FOR SKY/POP/HRLY T/DP/WINDS. ADJUSTED FOR COLLABORATION AND CONSISTENCY. LOADED NAWAVE4 FOR SEAS IN THE COASTAL WATERS. PLUS 25 PERCENT FOR GUSTS OVER THE WATERS...15 PERCENT OVER LAND. && .AVIATION /18Z MONDAY THROUGH SATURDAY/... NEAR TERM: CURRENT MVFR CEILINGS WILL LOWER THIS EVENING, BECOMING IFR BY MIDNIGHT AS RAIN SPREADS OVER THE REGION. WINDS WILL INCREASE AT THE SAME TIME, PEAKING 00Z-06Z TONIGHT. THE STRONGEST WINDS WILL BE AT THE TWO SOUTHERN TERMINALS, WHERE GUSTS OF 35 TO 40 KT ARE POSSIBLE. IN ADDITION, LOW LEVEL WIND SHEAR IS EXPECTED THROUGH MUCH OF THE NIGHT. WINDS WILL LET UP GRADUALLY AFTER 06Z, BUT EXPECT IFR CONDITIONS AND WIDESPREAD RAIN TO CONTINUE THROUGH TUESDAY. SHORT TERM: XPCT MSLY IFR TUE NGT THRU WED WITH CONDITIONS IMPROVING TO MVFR ALL SITES WED NGT. MVFR CONDITIONS XPCTD NRN TAF SITES THU THRU SAT WITH MSLY VFR XPCTD DOWNEAST SITES. && .MARINE... NEAR TERM: WINDS AND WAVES WILL CONTINUE TO BUILD OVER THE WATERS THIS EVENING. WINDS ARE ALREADY GUSTING IN EXCESS OF 35 KT AND SHOULD PEAK 55 TO 60 KT THIS EVENING. SEAS ARE RUNNING AROUND 10 FT AND WILL PEAK 20-25 FT OVERNIGHT. CONDITIONS WILL GRADUALLY IMPROVE THEREAFTER BUT WILL REMAIN ABOVE SMALL CRAFT CRITERIA THROUGH AT LEAST TUESDAY NIGHT. THEREFORE, ADDITIONAL HEADLINES WILL BE NEEDED AFTER THE STORM WARNING EXPIRES. SEE BELOW FOR ADDITIONAL DETAILS. SHORT TERM: AT LEAST SCA CONDITIONS WILL CONT THRU ALL OF THE SHORT TERM AS WINDS AND SEAS ONLY SLOWLY SUBSIDE THRU THU. WE WENT ABOUT A FOOT ABV WW3 WV GUIDANCE AT THE START OF THE PD TUES EVE AND THEN BLENDED WITH WW3 BY THU. && .HYDROLOGY... THE FLOOD WATCH REMAINS IN PLACE FOR TONIGHT INTO TUESDAY NIGHT. TOTAL RAINFALL THROUGH WEDNESDAY IS EXPECTED TO BE 1 TO 3 INCHES WITH AMOUNTS OF 3 TO 3.5 INCHES POSSIBLE IN THE UPSLOPE REGIONS OF CENTRAL MAINE. THIS INCLUDES THE MOUNT KATAHDIN AND MOOSEHEAD LAKE REGIONS. FOR NOW, IT STILL LOOKS LIKE THE MAIN THREAT WILL BE NUISANCE FLOODING RESULTING FROM CLOGGED STORM DRAINS AND STANDING WATER. HOWEVER, NOTED THAT THE LATEST FORECAST FOR THE PISCATAQUIS RIVER AT DOVER-FOXCROFT TAKES THE RIVER ABOVE ACTION STAGE WEDNESDAY AFTERNOON. GIVEN THAT THIS IS WHERE THE HEAVIEST RAIN IS EXPECTED, THE PISCATAQUIS AS WELL AS THE KINGSBURY AND ANY OTHER SMALL STREAMS WILL HAVE TO BE MONITORED. ALSO NOTED THAT HPC HAS INCLUDED ALL OF OUR FORECAST AREA SOUTH OF ABOUT HOULTON IN A SLIGHT CHANCE OF EXCEEDING FLASH FLOOD GUIDANCE IN THEIR DAY 2 EXCESSIVE RAIN OUTLOOK. WHILE NO MAJOR FLOODING IS ANTICIPATED AT THIS TIME, ALL WATERWAYS IN THIS OUTLOOK AREA, ESPECIALLY THE SMALLER STREAMS, WILL HAVE TO BE MONITORED FOR THE NEXT FEW DAYS. && .TIDES/COASTAL FLOODING... LATEST EXTRA-TROPICAL STORM SURGE INDICATES A 1 TO 2 FT STORM SURGE WITH TNGTS HI TIDE PLUS WIND SPEED SURGE. THIS SHOULD KEEP STORM TIDE MSLY BELOW 13 FEET. WITH WIND DIRECTION PARALLEL TO COAST LIMITED PILE UP OF WATER WILL OCCUR DUE TO EKMAN EFFECT... WHICH SHOULD COVER NHC`S PUBLIC BULLETIN MENTIONING LOCALLY UP TO A MAX OF 3 FT SURGE. EVEN SO...AT THIS TIME...ONLY MINIMUM FLOOD LEVELS WITH BAR HARBOR MAXIMUM (ASTRONOMICAL PLUS STORM SURGE TIDE) AT OR BELOW 14 FEET...ESPECIALLY WITHOUT ONSHORE FLOW TO SUPPLEMENT TIDE AT HEAD OF CONVERGENT BAYS SUCH AS MACHIAS AND PENOBSCOT BAYS. THIS IMPLIES ONLY A FEW TO SCATTERED LOCATIONS THAT MAY EXPERIENCE MINOR COASTAL FLOODING ATTM. && .CAR WATCHES/WARNINGS/ADVISORIES... ME...FLOOD WATCH FROM 8 PM EDT THIS EVENING THROUGH LATE TUESDAY NIGHT FOR MEZ004>006-010-011-015>017-031-032. WIND ADVISORY UNTIL 8 AM EDT TUESDAY FOR MEZ003>006-010-011- 031-032. HIGH WIND WARNING UNTIL 8 AM EDT TUESDAY FOR MEZ015>017-029- 030. COASTAL FLOOD ADVISORY FROM 9 PM THIS EVENING TO 2 AM EDT TUESDAY FOR MEZ029-030. MARINE...STORM WARNING UNTIL 8 AM EDT TUESDAY FOR ANZ050>052. && $$ NEAR TERM...HASTINGS SHORT TERM...VJN LONG TERM...NORTON AVIATION...HASTINGS MARINE...HASTINGS/VJN HYDROLOGY...HASTINGS TIDES/COASTAL FLOODING...VJN
000 WTNT43 KNHC 292058 TCDAT3 HURRICANE SANDY DISCUSSION NUMBER 30 NWS NATIONAL HURRICANE CENTER MIAMI FL AL182012 500 PM EDT MON OCT 29 2012 SANDY IS MAINTAINING A SMALL AREA OF DEEP CONVECTION NEAR THE CENTER...WITH BOTH AIR FORCE RESERVE RECONNAISSANCE AIRCRAFT DATA AND VARIOUS MICROWAVE SATELLITE DATA INDICATING A 20 N MI DIAMETER EYE HAS DEVELOPED SINCE THE PREVIOUS ADVISORY. MAXIMUM 700 MB FLIGHT-LEVEL WINDS HAVE BEEN 94 KT IN THE SOUTHERN QUADRANT...AND SFMR-ADJUSTED SURFACE WINDS OF 80-83 KT HAVE BEEN OBSERVED IN THE SOUTHWESTERN QUADRANT MORE THAN 90 N MI FROM THE CENTER. THE AIRCRAFT DATA ALSO INDICATE THAT THE CENTRAL PRESSURE HAS FALLEN A LITTLE...TO ABOUT 943 MB. BASED ON THE LATEST RECONNAISSANCE DATA...THE INITIAL INTENSITY HAS BEEN INCREASED TO 80 KT. RECONNAISSANCE CENTER FIXES INDICATE THAT SANDY HAS BEEN GRADUALLY TURNING TO THE LEFT AND IS NOW MOVING NORTH-NORTHWESTWARD OR ABOUT 330/16 KT. THE LATEST RECON FIXES HAVE BEEN FALLING ON THE PREVIOUS FORECAST TRACK...AND SO HAVE THE LATEST 12Z NHC FORECAST MODELS. THEREFORE...NO SIGNIFICANT CHANGES TO THE ADVISORY PREVIOUS TRACK OR REASONING ARE REQUIRED. SANDY IS NOW LOCATED NORTH OF THE AXIS OF A STRONG NEGATIVELY TILTED MID-/UPPER-LEVEL TROUGH...AND THE HURRICANE SHOULD TURN NORTHWESTWARD VERY SOON. LANDFALL ALONG OR JUST SOUTH OF THE SOUTHERN NEW JERSEY COAST IS EXPECTED LATE THIS EVENING...AT WHICH TIME A TURN TO THE WEST-NORTHWEST IS EXPECTED. AFTER MOVING INLAND OVER THE MID-ATLANTIC STATES A DECREASE IN FORWARD SPEED IS EXPECTED. BY 48 HOURS...THE POST-TROPICAL CYCLONE IS FORECAST TO MOVE NORTHWARD AND THEN NORTHEASTWARD. THE OFFICIAL NHC FORECAST TRACK IS SIMILAR TO THE PREVIOUS ADVISORY TRACK...AND LIES CLOSE TO A BLEND OF THE CONSENSUS MODELS TV15 AND TVCN. SANDY IS CURRENTLY TRAVERSING A NARROW RIDGE OF WARM SSTS AROUND 27C...WHICH ARE ASSOCIATED WITH THE GULF STREAM. THIS EXTRA LOW-LEVEL HEAT INPUT HAS LIKELY CONTRIBUTED TO THE RECENT INCREASE IN CONVECTION AROUND THE EYE. HOWEVER...SANDY WILL BE MOVING OVER THE NORTH WALL OF THE GULFSTREAM WITHIN THE NEXT 3 HOURS...WHICH WILL BRING A HALT TO ANY SIGNIFICANT INNER-CORE CONVECTIVE DEVELOPMENT. HOWEVER...THIS SHOULD HAVE LITTLE IMPACT ON THE OVERALL INTENSITY OR THE SIZE OF THE EXTREMELY LARGE WIND FIELD THAT IS NOW MORE THAN 1000 N MI IN DIAMETER. AT THE MOMENT... HURRICANE FORCE WINDS ARE ONLY OCCURRING IN THE SOUTHWEST QUADRANT...BUT MODEL GUIDANCE SUGGESTS THAT THESE COULD SPREAD INTO THE NORTHERN SEMICIRCLE BEFORE LANDFALL. SURFACE DATA INDICATE THAT WELL-DEFINED WARM AND COLD FRONTS LIE VERY NEAR THE CENTER OF SANDY...AND THE COMBINATION OF COLDER OCEAN WATER AND NEARBY FRONTAL SYSTEMS ARE EXPECTED TO RESULT IN EXTRATROPICAL TRANSITION BEFORE THE CENTER OF THE CYCLONE REACHES THE COAST. HOWEVER...THIS TRANSFORMATION WILL NOT DIMINISH THE OVERALL IMPACTS FROM WINDS TO HURRICANE STRENGTH...LIFE-THREATENING STORM SURGE... AND FLOODING RAINS ASSOCIATED WITH THIS DANGEROUS WEATHER SYSTEM. BASED ON THE GLOBAL MODELS...THE CYCLONE SHOULD WEAKEN FAIRLY RAPIDLY AFTER LANDFALL. INTERESTS ARE REMINDED NOT TO FOCUS ON THE CENTER OR THE EXACT FORECAST TRACK OF THIS SYSTEM...SINCE STRONG WINDS COVER AN AREA SEVERAL HUNDRED MILES ACROSS...AND THE HIGHEST WINDS WILL NOT NECESSARILY BE NEAR THE CENTER...ESPECIALLY JUST A FEW HUNDRED FEET ABOVE THE GROUND. AS NOTED IN PREVIOUS ADVISORIES...TO AVOID A HIGHLY DISRUPTIVE CHANGE FROM TROPICAL TO NON-TROPICAL WARNINGS WHEN SANDY BECOMES POST-TROPICAL...THE WIND HAZARD NORTH OF THE TROPICAL STORM WARNING AREA WILL CONTINUE TO BE CONVEYED THROUGH HIGH WIND WATCHES AND WARNINGS ISSUED BY LOCAL NATIONAL WEATHER SERVICE OFFICES. FORECAST POSITIONS AND MAX WINDS INIT 29/2100Z 38.8N 74.4W 80 KT 90 MPH 12H 30/0600Z 39.8N 76.6W 65 KT 75 MPH...POST-TROP/EXTRATROP 24H 30/1800Z 40.4N 78.3W 50 KT 60 MPH...POST-TROP/EXTRATROP 36H 31/0600Z 41.3N 78.2W 40 KT 45 MPH...POST-TROP/EXTRATROP 48H 31/1800Z 42.8N 77.5W 30 KT 35 MPH...POST-TROP/EXTRATROP 72H 01/1800Z 45.1N 75.5W 30 KT 35 MPH...POST-TROP/EXTRATROP 96H 02/1800Z 46.3N 72.2W 25 KT 30 MPH...POST-TROP/EXTRATROP 120H 03/1800Z 47.5N 65.5W 20 KT 25 MPH...POST-TROP/EXTRATROP $$ FORECASTER STEWART
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