WTNT41 KNHC 290238
TCDAT1
 
TROPICAL STORM KIRK DISCUSSION NUMBER   2
NWS NATIONAL HURRICANE CENTER MIAMI FL       AL112012
1100 PM AST TUE AUG 28 2012
 
A LARGE CONVECTIVE BURST...WITH A LARGE AREA OF CLOUD TOP
TEMPERATURES COLDER THAN -70C...HAS PERSISTED NEAR AND TO THE NORTH
OF THE CENTER OF THE TROPICAL CYCLONE FOR THE LAST SEVERAL HOURS.
AN ASCAT PASS FROM 2338 UTC SHOWED RELIABLE WIND VECTORS NEAR 40 KT
OR PERHAPS A LITTLE HIGHER. THEREFORE...THE INITIAL INTENSITY IS
CONSERVATIVELY SET AT 40 KT...AND THE SYSTEM IS UPGRADED TO
TROPICAL STORM KIRK. THE INTENSITY FORECAST IS TRICKY. THE SHIPS
MODEL SHOWS SOUTHWESTERLY SHEAR REMAINING GENERALLY BETWEEN 15 AND
20 KT FOR THE NEXT SEVERAL DAYS. IN ADDITION...GOES-R IMAGERY SHOWS
A SIGNIFICANT AMOUNT OF DRY AIR WEST OF THE CYCLONE. WHILE THESE
CONDITIONS SEEM UNFAVORABLE FOR SIGNIFICANT INTENSIFICATION...THE
SHIPS AND LGEM MODELS SUGGEST THAT KIRK COULD BECOME A HURRICANE IN
A FEW DAYS. THE OFFICIAL FORECAST HAS BEEN ADJUSTED SIGNIFICANTLY
UPWARD BUT IS STILL BELOW THE STATISTICAL-DYNAMICAL GUIDANCE.
 
RECENT MICROWAVE DATA HAS HELPED LOCATE THE CENTER OF KIRK...AND THE
INITIAL MOTION ESTIMATE IS A MORE CONFIDENT 280/10.  A CONTINUED
WESTWARD TO WEST-NORTHWESTWARD MOTION AT ABOUT THE SAME SPEED IS
EXPECTED DURING THE NEXT DAY OR TWO. AFTER THAT TIME...A GRADUAL
TURN TO TOWARD THE NORTH AND THEN NORTHEAST WITH A FASTER FORWARD
SPEED IS FORECAST AS THE SYSTEM REACHES THE WESTERN EDGE OF THE
SUBTROPICAL RIDGE AND BECOMES INFLUENCED BY AN APPROACHING LARGE-
SCALE TROUGH.  THE LATEST GFS RUN HAS A MUCH DEEPER SYSTEM AND...AS
A RESULT...HAS SHIFTED WELL TO THE EAST WITH RECURVATURE OCCURRING
AROUND 50W. THE NEW OFFICIAL NHC FORECAST CONSIDERS THE GFS AN
OUTLIER AT THIS TIME AND REMAINS ON THE WEST SIDE OF THE MODEL
GUIDANCE ENVELOPE...CLOSEST TO THE ECMWF SOLUTION.
 
 
FORECAST POSITIONS AND MAX WINDS
 
INIT  29/0300Z 23.9N  45.0W   40 KT  45 MPH
 12H  29/1200Z 24.2N  46.6W   45 KT  50 MPH
 24H  30/0000Z 24.5N  48.6W   50 KT  60 MPH
 36H  30/1200Z 25.0N  50.9W   55 KT  65 MPH
 48H  31/0000Z 26.0N  52.9W   55 KT  65 MPH
 72H  01/0000Z 29.0N  55.3W   55 KT  65 MPH
 96H  02/0000Z 34.8N  52.9W   55 KT  65 MPH
120H  03/0000Z 42.3N  44.9W   55 KT  65 MPH
 
$$
FORECASTER KIMBERLAIN/CANGIALOSI
 

WTNT41 KNHC 290831
TCDAT1
 
TROPICAL STORM KIRK DISCUSSION NUMBER   3
NWS NATIONAL HURRICANE CENTER MIAMI FL       AL112012
500 AM AST WED AUG 29 2012
 
ALTHOUGH CLOUD TOPS HAVE WARMED DURING THE LAST FEW HOURS...KIRK IS
STILL PRODUCING A FAIR AMOUNT OF DEEP CONVECTION MAINLY TO THE
NORTH OF THE ESTIMATED LOW-LEVEL CENTER. THE INITIAL WIND SPEED IS
HELD AT 40 KT BASED ON THE EARLIER ASCAT DATA AND A CONSENSUS OF
THE DVORAK CLASSIFICATIONS FROM TAFB AND SAB. SOUTHWESTERLY
VERTICAL WIND SHEAR OF 15 TO 20 KT IS EXPECTED TO SLACKEN SOME
DURING THE NEXT FEW DAYS. SINCE KIRK IS FORECAST TO REMAIN OVER
WATERS WARMER THAN 26C FOR THE NEXT 4 DAYS AND BECAUSE OF THE
ANTICIPATED MORE FAVORABLE UPPER-LEVEL WIND PATTERN...STRENGTHENING
SEEMS LIKELY.  THE OFFICIAL FORECAST HAS BEEN ADJUSTED UPWARD FROM
THE PREVIOUS ONE AND IS NEAR THE INTENSITY MODEL CONSENSUS. BY THE
END OF THE FORECAST PERIOD...KIRK IS EXPECTED TO BE OVER VERY COOL
WATERS AND IN STRONG SOUTHWESTERLY SHEAR. THESE FACTORS SHOULD
CAUSE THE CYCLONE TO LOSE ITS TROPICAL CHARACTERISTICS.
 
THE INITIAL MOTION IS 290/8. A CONTINUED WEST-NORTHWEST TO NORTHWEST
MOTION AT ABOUT THE SAME FORWARD SPEED IS EXPECTED DURING THE NEXT
24 TO 36 HOURS. BEYOND THAT...A TURN TO THE NORTH AND THEN
NORTHEAST WITH A PROGRESSIVELY FASTER FORWARD SPEED IS ANTICIPATED
AS KIRK MOVES WITHIN THE STRONG FLOW TO THE EAST OF AN APPROACHING
TROUGH. THE OFFICIAL FORECAST HAS BEEN ADJUSTED TO THE RIGHT TO
COME INTO BETTER AGREEMENT WITH THE LATEST MODEL RUNS...BUT IT STILL
LIES ON THE WEST SIDE OF THE GUIDANCE ENVELOPE.
 
FORECAST POSITIONS AND MAX WINDS
 
INIT  29/0900Z 24.3N  45.3W   40 KT  45 MPH
 12H  29/1800Z 24.7N  46.7W   45 KT  50 MPH
 24H  30/0600Z 25.3N  48.7W   50 KT  60 MPH
 36H  30/1800Z 26.4N  50.5W   55 KT  65 MPH
 48H  31/0600Z 28.1N  51.7W   55 KT  65 MPH
 72H  01/0600Z 32.5N  51.5W   65 KT  75 MPH
 96H  02/0600Z 38.0N  46.5W   65 KT  75 MPH
120H  03/0600Z 46.0N  37.0W   65 KT  75 MPH...POST-TROP/EXTRATROP
 
$$
FORECASTER CANGIALOSI
 

WTNT41 KNHC 291438
TCDAT1
 
TROPICAL STORM KIRK DISCUSSION NUMBER   4
NWS NATIONAL HURRICANE CENTER MIAMI FL       AL112012
1100 AM AST WED AUG 29 2012
 
WHILE KIRK HAS A DISTINCT MID-LEVEL CENTER ON THE SOUTHWEST SIDE OF
THE RELATIVELY DISORGANIZED CONVECTIVE CANOPY...THE LOW-LEVEL
CIRCULATION APPEARS TO BE DISPLACED A LITTLE TO THE WEST DUE TO
ABOUT 15 KT OF WESTERLY SHEAR OVER THE CYCLONE. THE INITIAL
INTENSITY IS HELD AT 40 KT BASED ON A BLEND OF DVORAK FINAL-T
NUMBERS FROM SAB AND TAFB. IN THE SHORT TERM THE COMBINATION OF DRY
AIR AROUND THE CYCLONE AND SHEAR OF 10 TO 15 KT SUGGESTS THAT ANY
INTENSIFICATION WILL BE GRADUAL FOR THE NEXT DAY OR SO. THE NEW NHC
FORECAST HAS BEEN NUDGED SLIGHTLY DOWNWARD THROUGH 36 HOURS BUT IS
STILL ABOVE MOST OF THE GUIDANCE THROUGH THAT TIME. AFTER THAT TIME 
AS KIRK RECURVES AND THE SHEAR DECREASES...STRENGTHENING TO
HURRICANE INTENSITY IS FORECAST BY 72 HOURS IN AGREEMENT WITH THE
INTENSITY CONSENSUS. KIRK IS EXPECTED TO BECOME EXTRATROPICAL BY
THE END OF THE PERIOD WITH SLOW WEAKENING UNDERWAY BY THAT TIME. 

MICROWAVE IMAGERY SUGGESTS THAT THE CENTER WAS LOCATED WEST OF
PREVIOUS ESTIMATES OVERNIGHT...AND THE INITIAL MOTION ESTIMATE IS A
RATHER UNCERTAIN 290/10. KIRK WILL TURN NORTHWESTWARD IN THE NEXT
36 HOURS INTO A BREAK IN THE SUBTROPICAL RIDGE...AND THEN TURN
NORTHWARD AND NORTHEASTWARD AS THE CYCLONE RECURVES INTO THE
MID-LATITUDE WESTERLIES LATE IN THE PERIOD. WHILE THE MODEL
GUIDANCE IS IN AGREEMENT ON THIS OVERALL SCENARIO...THERE REMAIN
SOME SIGNIFICANT DETAIL DIFFERENCES IN THE MOTION IN THE SHORT
TERM. THE ECMWF MODEL KEEPS KIRK WEAKER AND SHOWS MORE GRADUAL
RECURVATURE...WHILE THE GFS...GEFS ENSEMBLE MEAN...AND THE REGIONAL
HURRICANE MODELS SHOW A SHARPER RECURVATURE. THE NEW NHC TRACK IS
FASTER THROUGH 36 HOURS AND A LITTLE TO THE LEFT OF THE PREVIOUS
FORECAST THROUGH THE PERIOD...LARGELY DUE TO THE INITIAL POSITION
AND MOTION. THE NHC TRACK IS CLOSE TO THE LATEST TVCA CONSENSUS
THROUGH 48 HOURS AND A LITTLE TO THE LEFT AFTERWARD...CLOSE TO A
BLEND OF THE GFS AND ECMWF AT DAYS 3 THROUGH 5. 
 
FORECAST POSITIONS AND MAX WINDS
 
INIT  29/1500Z 24.7N  46.9W   40 KT  45 MPH
 12H  30/0000Z 25.3N  48.4W   45 KT  50 MPH
 24H  30/1200Z 26.2N  50.2W   45 KT  50 MPH
 36H  31/0000Z 27.8N  51.7W   50 KT  60 MPH
 48H  31/1200Z 29.8N  52.2W   55 KT  65 MPH
 72H  01/1200Z 34.5N  50.5W   65 KT  75 MPH
 96H  02/1200Z 40.5N  44.0W   65 KT  75 MPH
120H  03/1200Z 48.5N  32.5W   55 KT  65 MPH...POST-TROP/EXTRATROP
 
$$
FORECASTER BRENNAN
 

WTNT41 KNHC 292031
TCDAT1
 
TROPICAL STORM KIRK DISCUSSION NUMBER   5
NWS NATIONAL HURRICANE CENTER MIAMI FL       AL112012
500 PM AST WED AUG 29 2012

DEEP CONVECTION HAS BLOSSOMED OVER THE CENTER OF KIRK THIS
AFTERNOON...BUT CLOUD TOP TEMPERATURES HAVE BEGUN TO WARM AGAIN
OVER THE PAST HOUR OR SO. THE INITIAL INTENSITY IS SET TO 45 KT
BASED ON THE LATEST DVORAK ESTIMATES FROM TAFB AND SAB. IN THE
SHORT TERM...MODERATE SHEAR VALUES AND SOME DRY AIR IN THE
ENVIRONMENT WOULD SEEM TO SUPPORT ONLY GRADUAL STRENGTHENING IN THE
NEXT DAY OR SO. BEYOND 36 HOURS...THE SHEAR IS EXPECTED TO DECREASE
AS KIRK MOVES AROUND THE WESTERN SIDE OF THE SUBTROPICAL RIDGE...
AND MOST OF THE GUIDANCE SHOWS KIRK BECOMING A HURRICANE BY 72
HOURS. WEAKENING IS EXPECTED BY DAY 4 AS THE SHEAR INCREASES
DRAMATICALLY AND KIRK MOVES OVER COOLER WATERS BEFORE THE CYCLONE
IS ABSORBED BY DAY 5. THROUGH THE PERIOD THE NHC FORECAST IS CLOSE
TO THE VARIOUS INTENSITY CONSENSUS AIDS. 

THE CENTER NOW APPEARS TO BE EMBEDDED UNDER THE DEEP CONVECTION AND
IS ABOUT A HALF A DEGREE TO THE RIGHT OF THE PREVIOUS FORECAST. THE
INITIAL MOTION ESTIMATE IS A RATHER UNCERTAIN 300/09. OVERALL THE
TRACK FORECAST REASONING REMAINS UNCHANGED...AS KIRK WILL MOVE
AROUND THE WESTERN SIDE OF THE SUBTROPICAL RIDGE IN THE NEXT 24
HOURS AND THEN BEGIN TO ACCELERATE NORTHWARD AND NORTHEASTWARD AS
THE CYCLONE RECURVES AHEAD OF AN AMPLIFYING MID-LATITUDE TROUGH.
MOST OF THE GUIDANCE HAS SHIFTED TOWARD A SHARPER RECURVATURE THIS
CYCLE WITH A FASTER FORWARD SPEED LATE IN THE PERIOD. FOR
EXAMPLE...THE ECMWF...WHICH WAS ON THE LEFT SIDE OF THE GUIDANCE
ENVELOPE EARLIER NOW LIES CLOSER TO THE MIDDLE OF THE ENVELOPE BUT
IS EAST OF THE CONSENSUS. OVERALL THE MODEL CONSENSUS HAS SHIFTED
RIGHTWARD THIS CYCLE...AND THIS...IN COMBINATION WITH THE
ADJUSTMENT IN THE INITIAL POSITION AND MOTION...RESULTS IN A
RIGHTWARD SHIFT OF ABOUT A DEGREE IN THE NHC TRACK IN THE FIRST 36
HOURS. BEYOND THAT TIME...THE NHC FORECAST IS BLENDED BACK TOWARD
THE OLD TRACK...BUT IS FASTER. THROUGHOUT THE PERIOD THE NHC TRACK
IS NEAR THE TVCA CONSENSUS. 
 
FORECAST POSITIONS AND MAX WINDS
 
INIT  29/2100Z 25.3N  47.6W   45 KT  50 MPH
 12H  30/0600Z 26.1N  48.9W   50 KT  60 MPH
 24H  30/1800Z 27.7N  50.4W   50 KT  60 MPH
 36H  31/0600Z 29.6N  51.3W   55 KT  65 MPH
 48H  31/1800Z 31.9N  51.1W   60 KT  70 MPH
 72H  01/1800Z 38.0N  46.0W   70 KT  80 MPH
 96H  02/1800Z 45.5N  37.0W   60 KT  70 MPH
120H  03/1800Z...ABSORBED
 
$$
FORECASTER BRENNAN
 

WTNT41 KNHC 300259
TCDAT1
 
TROPICAL STORM KIRK DISCUSSION NUMBER   6
NWS NATIONAL HURRICANE CENTER MIAMI FL       AL112012
1100 PM AST WED AUG 29 2012
 
THE SMALL CLOUD PATTERN ASSOCIATED WITH KIRK HAS BECOME BETTER
ORGANIZED DURING THE LAST SEVERAL HOURS. DEEP CONVECTION HAS FULLY
WRAPPED AROUND THE CENTER IN THE FORM OF A CENTRAL DENSE OVERCAST.
AN EARLIER WINDSAT PASS SHOWED A CLOSED LOW-LEVEL RING OF
CONVECTION...LIKELY PORTENDING AN INTENSIFICATION PHASE. DVORAK
T-NUMBERS AT 0000 UTC WERE A CONSENSUS 3.0/45 KT. A 0056 UTC ASCAT
PASS SHOWED SEVERAL RELIABLE 45 KT WIND VECTORS. SINCE THAT
TIME...AN INTERMITTENT EYE HAS BEEN VISIBLE BUT THAT FEATURE HAS NOT
PERSISTED. THE INITIAL INTENSITY ESTIMATE IS RAISED TO 50 KT BASED
ON THE OVERALL INCREASE IN ORGANIZATION.
 
A SERIES OF MORE RELIABLE FIXES HAS YIELDED A MORE CONFIDENT INITIAL
MOTION OF 300/08.  KIRK IS ALREADY ROUNDING THE WESTERN PERIPHERY
OF A SUBTROPICAL RIDGE OVER THE EASTERN ATLANTIC...AND GLOBAL
MODELS RESPOND BY SHOWING THE CYCLONE TURNING NORTHWESTWARD AND THEN
NORTHWARD DURING THE NEXT DAY OR SO. A RAPIDLY ADVANCING SHORTWAVE
TROUGH CURRENTLY OVER THE NORTHEASTERN UNITED STATES WILL SWEEP
SOUTHEASTWARD AND ERODE THE RIDGE FURTHER IN ABOUT TWO DAYS...
LEADING TO A RECURVATURE OF KIRK INTO THE WESTERLIES.  A MORE
COMPLEX SHORTWAVE TROUGH MOVING THROUGH THE CANADIAN MARITIME
PROVINCES AROUND THAT TIME WILL CAUSE KIRK TO ACCELERATE FOR THE
REMAINDER OF THE FORECAST.  THE NEW NHC TRACK FORECAST IS SHIFTED A
BIT TO THE RIGHT...AND IS IN GOOD AGREEMENT WITH THE GENERALLY
RELIABLE GFS AND ECWMF MODEL SOLUTIONS.
 
SOUTHWESTERLY SHEAR OVER KIRK APPEARS TO BE RELAXING AND IS EXPECTED
TO REMAIN LOW FOR AT LEAST A COUPLE OF DAYS WHILE THE CYCLONE
REMAINS OVER WARM WATERS. KIRK ALSO SEEMS TO BE AT LEAST PARTIALLY
INSULATED FROM DRY AIR LURKING TO THE NORTHWEST. STRENGTHENING IS
FORECAST UNTIL WESTERLY SHEAR INCREASES IN ABOUT 72 HOURS. THE
INCREASE IN SHEAR ALONG WITH THE PASSAGE OF KIRK OF PROGRESSIVE
LOWER SEA SURFACE TEMPERATURES SHOULD LEAD TO WEAKENING AROUND THAT
TIME. GLOBAL MODELS SHOW A RAPIDLY ADVANCING FRONTAL BOUNDARY
ENCROACHING ON KIRK IN 72-96 HOURS...AND THIS FEATURE IS FORECAST
TO ABSORB THE CYCLONE IN ABOUT 96 HOURS. THE NHC INTENSITY FORECAST
IS ADJUSTED UPWARD OVER THE PREVIOUS ONE BASED ON NOT ONLY SHORT-
TERM TRENDS BUT ALSO THE LATEST GUIDANCE SHOWING A STRONGER SYSTEM.
  
 
FORECAST POSITIONS AND MAX WINDS
 
INIT  30/0300Z 25.9N  48.3W   50 KT  60 MPH
 12H  30/1200Z 26.9N  49.4W   55 KT  65 MPH
 24H  31/0000Z 28.6N  50.5W   60 KT  70 MPH
 36H  31/1200Z 30.6N  50.8W   65 KT  75 MPH
 48H  01/0000Z 33.3N  49.7W   70 KT  80 MPH
 72H  02/0000Z 39.4N  43.7W   80 KT  90 MPH
 96H  03/0000Z 47.1N  34.9W   70 KT  80 MPH
120H  04/0000Z...DISSIPATED
 
$$
FORECASTER KIMBERLAIN
 

WTNT41 KNHC 300840
TCDAT1
 
TROPICAL STORM KIRK DISCUSSION NUMBER   7
NWS NATIONAL HURRICANE CENTER MIAMI FL       AL112012
500 AM AST THU AUG 30 2012
 
CONVENTIONAL AND MICROWAVE SATELLITE IMAGERY HAVE SHOWN HINTS OF AN
EYE-LIKE FEATURE DURING THE PAST FEW HOURS.  DVORAK ESTIMATES FROM
TAFB AND SAB ARE AT 45 KT AND 55 KT...RESPECTIVELY...AND THE
ADVISORY INTENSITY IS SET AT THE HIGHER OF THE TWO NUMBERS GIVEN
THE MICROWAVE PRESENTATION.  KIRK IS EXPECTED TO REMAIN IN A
LOW-SHEAR ENVIRONMENT AND OVER SSTS OF AT LEAST 26C FOR THE NEXT 48
TO 72 HOURS...AND CONTINUED STRENGTHENING IS EXPECTED DURING THAT
TIME PERIOD.  VERY STRONG SOUTHWESTERLY SHEAR SHOULD BEGIN
AFFECTING THE CYCLONE FROM 72 HOURS AND BEYOND...AT WHICH POINT
KIRK SHOULD BEGIN TO WEAKEN.  KIRK IS A SMALL TROPICAL CYCLONE AND
IS THEREFORE PRONE TO QUICKER STRENGTHENING THAN A LARGE CYCLONE. 
BECAUSE OF THAT...THE NHC INTENSITY FORECAST IS CLOSER TO THE
DYNAMICAL HURRICANE MODELS THAN THE STATISTICAL GUIDANCE.  THERE IS
SOME DISAGREEMENT ON WHEN KIRK WILL BECOME EXTRATROPICAL AND/OR
BECOME ABSORBED BY A FRONTAL BOUNDARY...WITH THE GFS HOLDING ON TO
A NON-FRONTAL LOW LONGER THAN THE OTHER GLOBAL MODELS.  THE
FORECAST SPLITS THE DIFFERENCE...MAKING KIRK EXTRATROPICAL IN 96
HOURS AND BECOMING ABSORBED BY A FRONT IN 120 HOURS.

THE INITIAL MOTION ESTIMATE IS 315/10.  KIRK IS ROUNDING THE WESTERN
PERIPHERY OF THE SUBTROPICAL RIDGE...AND IT SHOULD ALSO BEGIN TO
FEEL THE PRESENCE OF AN AMPLIFYING SHORTWAVE TROUGH OVER THE
WESTERN ATLANTIC DURING THE NEXT DAY OR SO.  THE TRACK GUIDANCE IS
IN GOOD AGREEMENT THAT THE CYCLONE WILL TURN NORTHWARD AND THEN
NORTHEASTWARD BEFORE IT BECOMES ABSORBED BY THE FRONT.  THE NEW
FORECAST IS SHIFTED JUST A BIT LEFT OF THE PREVIOUS ONE AND IS NEAR
THE MULTI-MODEL CONSENSUS TVCA AND TV15.
 
 
FORECAST POSITIONS AND MAX WINDS
 
INIT  30/0900Z 26.5N  49.0W   55 KT  65 MPH
 12H  30/1800Z 27.5N  50.1W   60 KT  70 MPH
 24H  31/0600Z 29.3N  50.8W   65 KT  75 MPH
 36H  31/1800Z 31.5N  50.8W   70 KT  80 MPH
 48H  01/0600Z 34.2N  49.3W   75 KT  85 MPH
 72H  02/0600Z 40.5N  43.0W   75 KT  85 MPH
 96H  03/0600Z 47.5N  32.5W   60 KT  70 MPH...POST-TROP/EXTRATROP
120H  04/0600Z...ABSORBED BY A FRONT
 
$$
FORECASTER BERG
 

WTNT41 KNHC 301459
TCDAT1
 
HURRICANE KIRK DISCUSSION NUMBER   8
NWS NATIONAL HURRICANE CENTER MIAMI FL       AL112012
1100 AM AST THU AUG 30 2012
 
KIRK HAS DEVELOPED A 10-NMI DIAMETER EYE IN VISIBLE SATELLITE
IMAGERY SINCE THE 12Z SATELLITE INTENSITY ESTIMATES OF T3.5/55-60
KT WERE RECEIVED FROM TAFB AND SAB. AS A RESULT...KIRK HAS BEEN
UPGRADED TO HURRICANE STATUS ON THIS ADVISORY. 

THE INITIAL MOTION ESTIMATE IS 325/10 KT. THERE IS NO SIGNIFICANT
CHANGE TO THE PREVIOUS TRACK FORECAST OR REASONING. KIRK IS ON
TRACK AND THE LATEST MODEL GUIDANCE IS NOW TIGHTLY CLUSTERED ABOUT
THE PREVIOUS FORECAST TRACK. THEREFORE...THE NEW FORECAST IS JUST
AN EXTENSION OF THE PREVIOUS ADVISORY TRACK...WHICH LIES ON TOP OF
THE NEARLY IDENTICAL TV15 AND TVCA CONSENSUS MODELS.

KIRK IS EXPECTED TO REMAIN IN A LOW-SHEAR ENVIRONMENT AND OVER SSTS
OF MORE THAN 26C FOR AT LEAST THE NEXT 48 HOURS...WHICH SHOULD
ALLOW FOR AT LEAST GRADUAL STRENGTHENING TO OCCUR. HOWEVER...SINCE
KIRK IS A SMALL SYSTEM...IT WILL BE SUSCEPTIBLE TO INTERMITTENT
INTRUSIONS OF DRY MID-LEVEL AIR THAT CAN BRIEFLY INTERRUPT THE
INTENSIFICATION PROCESS. BY 72 HOURS AND BEYOND...SOUTHWESTERLY
VERTICAL WIND SHEAR IS EXPECTED TO INCREASE AHEAD OF AN APPROACHING
MID-LATITUDE TROUGH...WHICH SHOULD BEGIN TO INDUCE GRADUAL
WEAKENING. BY 96 HOURS...THE COMBINATION OF STRONG SHEAR AND SSTS
LESS THAN 20C SHOULD RESULT IN KIRK BECOMING AN EXTRATROPICAL
CYCLONE. MERGER WITH A FRONTAL SYSTEM IS EXPECTED BY 120 HOURS. THE
INTENSITY FORECAST CLOSELY FOLLOWS THE CONSENSUS INTENSITY MODEL
IV15.
 
FORECAST POSITIONS AND MAX WINDS
 
INIT  30/1500Z 27.2N  49.5W   65 KT  75 MPH
 12H  31/0000Z 28.4N  50.3W   70 KT  80 MPH
 24H  31/1200Z 30.4N  50.6W   75 KT  85 MPH
 36H  01/0000Z 32.9N  49.8W   80 KT  90 MPH
 48H  01/1200Z 35.8N  47.5W   80 KT  90 MPH
 72H  02/1200Z 42.2N  40.2W   75 KT  85 MPH
 96H  03/1200Z 49.2N  29.9W   55 KT  65 MPH...POST-TROP/EXTRATROP
120H  04/1200Z...DISSIPATED
 
$$
FORECASTER STEWART
 

WTNT41 KNHC 302056
TCDAT1
 
HURRICANE KIRK DISCUSSION NUMBER   9
NWS NATIONAL HURRICANE CENTER MIAMI FL       AL112012
500 PM AST THU AUG 30 2012
 
KIRK HAS BEEN RAPIDLY INTENSIFYING OVER THE PAST 12-18 HOURS. THE
HURRICANE HAS MAINTAINED A 10-NMI DIAMETER EYE IN VISIBLE SATELLITE
IMAGERY...AND THE 18Z SATELLITE INTENSITY ESTIMATES WERE A CONSENSUS
T4.5/77 KT KT FROM TAFB AND SAB. GIVEN THAT THE CDO FEATURE HAS
EXPANDED AND TOPS HAVE CONTINUED TO COOL...THE INITIAL INTENSITY
HAS BEEN INCREASED TO 80 KT.
 
THE INITIAL MOTION ESTIMATE IS 330/11 KT. THERE REMAINS NO
SIGNIFICANT CHANGE TO THE PREVIOUS TRACK FORECAST OR REASONING.
KIRK CONTINUES ON TRACK AND THE 18Z MODEL GUIDANCE REMAINS TIGHTLY
CLUSTERED ABOUT THE PREVIOUS FORECAST TRACK. AS A RESULT...THE NEW
FORECAST IS JUST AN EXTENSION OF THE PREVIOUS ADVISORY TRACK...
WHICH LIES VERY CLOSE TO THE TV15 AND TVCA CONSENSUS MODELS.
 
KIRK APPEARS TO HAVE BEEN ABLE TO OVERCOME ANY DRY AIR ISSUES...SO
SOME ADDITIONAL STRENGTHENING IS FORECAST FOR THE NEXT 24 HOURS.
ALTHOUGH KIRK IS EXPECTED TO REMAIN A RELATIVELY COMPACT
CYCLONE...WHICH MAKES IT VULNERABLE TO SLIGHT INCREASES IN VERTICAL
SHEAR AND ENTRAINMENT OF NEARBY DRY AIR...THE CYCLONE COULD STILL
BECOME A MAJOR HURRICANE BEFORE WEAKENING BEGINS IN 36-48 HOURS. BY
96 HOURS...THE COMBINATION OF STRONG WESTERLY WIND SHEAR AND SSTS
LESS THAN 20C SHOULD RESULT IN KIRK BECOMING AN EXTRATROPICAL
CYCLONE. MERGER WITH A FRONTAL SYSTEM IS EXPECTED BY 120 HOURS. THE
INTENSITY FORECAST IS SIMILAR TO BUT SLIGHTLY HIGHER THAN THE SHIPS
AND LGEM MODEL CONSENSUS.

FORECAST POSITIONS AND MAX WINDS
 
INIT  30/2100Z 28.2N  50.3W   80 KT  90 MPH
 12H  31/0600Z 29.5N  50.8W   90 KT 105 MPH
 24H  31/1800Z 31.8N  50.5W   95 KT 110 MPH
 36H  01/0600Z 34.4N  49.0W   95 KT 110 MPH
 48H  01/1800Z 37.5N  46.1W   85 KT 100 MPH
 72H  02/1800Z 44.5N  37.5W   65 KT  75 MPH
 96H  03/1800Z 51.5N  25.0W   50 KT  60 MPH...POST-TROP/EXTRATROP
120H  04/1800Z...ABSORBED BY FRONTAL SYSTEM
 
$$
FORECASTER STEWART
 

WTNT41 KNHC 310249
TCDAT1
 
HURRICANE KIRK DISCUSSION NUMBER  10
NWS NATIONAL HURRICANE CENTER MIAMI FL       AL112012
1100 PM AST THU AUG 30 2012
 
KIRK CONTINUES TO MAINTAIN AN IMPRESSIVE CLOUD PATTERN...WITH A
SYMMETRIC CENTRAL DENSE OVERCAST COMPRISED OF COLD CLOUD TOP
TEMPERATURES.  ALTHOUGH THE EARLIER RAPID INTENSIFICATION PHASE
SEEMS TO HAVE LEVELED OFF...THE EYE HAS WARMED FURTHER AND BECOME
BETTER DEFINED IN THE LAST FEW HOURS. DVORAK INTENSITY ESTIMATES
ARE A CONSENSUS 4.5 FROM TAFB AND SAB...BUT THE LATEST ADT VALUES
HAVE BEEN RUNNING CLOSER TO T5.0. THE INITIAL INTENSITY ESTIMATE IS
RAISED TO 85 KT IN AGREEMENT WITH A BLEND OF THESE DATA SOURCES.
KIRK HAS ANOTHER DAY OR SO TRAVERSING WARM WATERS IN A RELATIVELY
LOW SHEAR ENVIRONMENT. THE CYCLONE ALSO HAS A WELL-ESTABLISHED
OUTFLOW SINK TO THE EAST AND IS FORECAST TO APPROACH A JET TO THE
NORTHWEST...WHICH COULD SERVE AS AN ADDITIONAL OUTFLOW CHANNEL.
THESE FACTORS...ALONG WITH THE STATISTICAL-DYNAMICAL GUIDANCE...
SUGGESTS A PEAK INTENSITY OCCURRING AROUND OR JUST AFTER THE POINT
OF RECURVATURE. A SHARP INCREASE IN SHEAR AND A TRACK OVER RAPIDLY
DECREASING SEA SURFACE TEMPERATURES BEYOND 48 HOURS SHOULD RESULT
IN STEADY OR EVEN RAPID WEAKENING. A QUICK-MOVING FRONTAL ZONE
SHOULD BEGIN TO OVERTAKE KIRK IN 2-3 DAYS...RESULTING IN
EXTRATROPICAL TRANSITION JUST AROUND 72 HOURS AND ABSORPTION IN 96
HOURS.  THE NHC INTENSITY FORECAST IS NEARLY IDENTICAL TO THE
PREVIOUS ONE...AND IS SLIGHTLY HIGHER THAN THE SHIPS/LGEM INTENSITY
AIDS.
 
THE INITIAL MOTION ESTIMATE HAS VEERED A HAIR TO THE RIGHT AND IS
335/10. THE TRACK FORECAST IS CLEAR-CUT. KIRK HAS REACHED THE
WESTERN END OF SUBTROPICAL RIDGE TO THE EAST AND SHOULD UNDERGO
RECURVATURE IN THE NEXT 24 HOURS. THE CYCLONE SHOULD THEN GRADUALLY
BECOME EMBEDDED IN MID-LATITUDE WESTERLIES...AND ACCELERATE AT WARP
SPEED WITH THE APPROACH OF A POTENT MID-LATITUDE SHORTWAVE OVER THE
CANADIAN MARITIME PROVINCES IN 36-48 HOURS. THE NEW TRACK FORECAST
IS VIRTUALLY UNCHANGED FROM THE PREVIOUS ONE...GIVEN THE EXCELLENT
AGREEMENT IN THE NUMERICAL MODEL GUIDANCE.
 
  
FORECAST POSITIONS AND MAX WINDS
 
INIT  31/0300Z 29.0N  50.7W   85 KT 100 MPH
 12H  31/1200Z 30.5N  50.8W   90 KT 105 MPH
 24H  01/0000Z 33.0N  50.0W   95 KT 110 MPH
 36H  01/1200Z 35.8N  47.9W   95 KT 110 MPH
 48H  02/0000Z 38.7N  44.5W   85 KT 100 MPH
 72H  03/0000Z 46.2N  34.3W   65 KT  75 MPH...POST-TROP/EXTRATROP
 96H  04/0000Z 52.0N  20.0W   45 KT  50 MPH...POST-TROP/EXTRATROP
120H  05/0000Z...DISSIPATED
 
$$
FORECASTER KIMBERLAIN
 

WTNT41 KNHC 310307
TCDAT1
 
HURRICANE KIRK DISCUSSION NUMBER  10...CORRECTED
NWS NATIONAL HURRICANE CENTER MIAMI FL       AL112012
1100 PM AST THU AUG 30 2012
 
CORRECTED TO CHANGE STATUS AT 120 HOURS TO ABSORBED BY FRONTAL ZONE

KIRK CONTINUES TO MAINTAIN AN IMPRESSIVE CLOUD PATTERN...WITH A
SYMMETRIC CENTRAL DENSE OVERCAST COMPRISED OF COLD CLOUD TOP
TEMPERATURES.  ALTHOUGH THE EARLIER RAPID INTENSIFICATION PHASE
SEEMS TO HAVE LEVELED OFF...THE EYE HAS WARMED FURTHER AND BECOME
BETTER DEFINED IN THE LAST FEW HOURS. DVORAK INTENSITY ESTIMATES
ARE A CONSENSUS 4.5 FROM TAFB AND SAB...BUT THE LATEST ADT VALUES
HAVE BEEN RUNNING CLOSER TO T5.0. THE INITIAL INTENSITY ESTIMATE IS
RAISED TO 85 KT IN AGREEMENT WITH A BLEND OF THESE DATA SOURCES.
KIRK HAS ANOTHER DAY OR SO TRAVERSING WARM WATERS IN A RELATIVELY
LOW SHEAR ENVIRONMENT. THE CYCLONE ALSO HAS A WELL-ESTABLISHED
OUTFLOW SINK TO THE EAST AND IS FORECAST TO APPROACH A JET TO THE
NORTHWEST...WHICH COULD SERVE AS AN ADDITIONAL OUTFLOW CHANNEL.
THESE FACTORS...ALONG WITH THE STATISTICAL-DYNAMICAL GUIDANCE...
SUGGESTS A PEAK INTENSITY OCCURRING AROUND OR JUST AFTER THE POINT
OF RECURVATURE. A SHARP INCREASE IN SHEAR AND A TRACK OVER RAPIDLY
DECREASING SEA SURFACE TEMPERATURES BEYOND 48 HOURS SHOULD RESULT
IN STEADY OR EVEN RAPID WEAKENING. A QUICK-MOVING FRONTAL ZONE
SHOULD BEGIN TO OVERTAKE KIRK IN 2-3 DAYS...RESULTING IN
EXTRATROPICAL TRANSITION JUST AROUND 72 HOURS AND ABSORPTION IN 96
HOURS.  THE NHC INTENSITY FORECAST IS NEARLY IDENTICAL TO THE
PREVIOUS ONE...AND IS SLIGHTLY HIGHER THAN THE SHIPS/LGEM INTENSITY
AIDS.
 
THE INITIAL MOTION ESTIMATE HAS VEERED A HAIR TO THE RIGHT AND IS
335/10. THE TRACK FORECAST IS CLEAR-CUT. KIRK HAS REACHED THE
WESTERN END OF SUBTROPICAL RIDGE TO THE EAST AND SHOULD UNDERGO
RECURVATURE IN THE NEXT 24 HOURS. THE CYCLONE SHOULD THEN GRADUALLY
BECOME EMBEDDED IN MID-LATITUDE WESTERLIES...AND ACCELERATE AT WARP
SPEED WITH THE APPROACH OF A POTENT MID-LATITUDE SHORTWAVE OVER THE
CANADIAN MARITIME PROVINCES IN 36-48 HOURS. THE NEW TRACK FORECAST
IS VIRTUALLY UNCHANGED FROM THE PREVIOUS ONE...GIVEN THE EXCELLENT
AGREEMENT IN THE NUMERICAL MODEL GUIDANCE.
 
  
FORECAST POSITIONS AND MAX WINDS
 
INIT  31/0300Z 29.0N  50.7W   85 KT 100 MPH
 12H  31/1200Z 30.5N  50.8W   90 KT 105 MPH
 24H  01/0000Z 33.0N  50.0W   95 KT 110 MPH
 36H  01/1200Z 35.8N  47.9W   95 KT 110 MPH
 48H  02/0000Z 38.7N  44.5W   85 KT 100 MPH
 72H  03/0000Z 46.2N  34.3W   65 KT  75 MPH...POST-TROP/EXTRATROP
 96H  04/0000Z 52.0N  20.0W   45 KT  50 MPH...POST-TROP/EXTRATROP
120H  05/0000Z...ABSORBED BY FRONTAL ZONE
 
$$
FORECASTER KIMBERLAIN
 

WTNT41 KNHC 310847
TCDAT1
 
HURRICANE KIRK DISCUSSION NUMBER  11
NWS NATIONAL HURRICANE CENTER MIAMI FL       AL112012
500 AM AST FRI AUG 31 2012
 
KIRK IS A SMALL-SIZE HURRICANE WITH A DISTINCT EYE SURROUNDED BY A
RING OF VERY DEEP CONVECTION.  BOTH OBJECTIVE AND SUBJECTIVE
T-NUMBERS WERE 5.0 AT 0600 UTC ON THE DVORAK SCALE GIVING AN
INITIAL INTENSITY OF 90 KNOTS. SINCE THAT TIME...THE CLOUD
PATTERN HAS IMPROVED...AND THE OBJECTIVE NUMBERS HAVE INCREASED.
THIS MEANS THAT THE WINDS COULD BE A LITTLE BIT HIGHER. HOWEVER...I
WOULD RATHER WAIT FOR THE PERSISTENCE OF THESE HIGHER T-NUMBERS
BEFORE ADJUSTING THE INTENSITY UPWARD...IF NECESSARY.  ALTHOUGH THE
SHEAR IS EXPECTED TO REMAIN LOW...KIRK ONLY HAS A 24-HOUR WINDOW TO
STRENGTHEN FURTHER BEFORE IT REACHES SEA SURFACE TEMPERATURES LOWER
THAN 27 DEGREES CELSIUS. THE HURRICANE SHOULD THEN BEGIN TO WEAKEN
AND LOSE TROPICAL CHARACTERISTICS. KIRK IS FORECAST TO BECOME
ABSORBED BY A FRONTAL SYSTEM IN ABOUT 4 DAYS OR EARLIER.

THE HURRICANE IS MOVING TOWARD THE NORTH-NORTHWEST OR 345 DEGREES AT
10 KNOTS...AND SOON IT SHOULD RECURVE AS IT BECOMES EMBEDDED WITHIN
THE SOUTHWESTERLY FLOW AHEAD OF AN AMPLIFYING MID-LATITUDE TROUGH.
KIRK SHOULD THEN MOVE NORTHEASTWARD AND ACCELERATE AS INDICATED BY
MOST OF THE TIGHTLY CLUSTERED TRACK GUIDANCE. SINCE THE STEERING
FLOW AROUND KIRK IS WELL ESTABLISHED...THERE IS HIGH CONFIDENCE IN
THE TRACK FORECAST.
 
 
FORECAST POSITIONS AND MAX WINDS
 
INIT  31/0900Z 30.1N  50.9W   90 KT 105 MPH
 12H  31/1800Z 31.7N  50.9W   95 KT 110 MPH
 24H  01/0600Z 34.5N  49.0W   90 KT 105 MPH
 36H  01/1800Z 37.5N  46.0W   85 KT 100 MPH
 48H  02/0600Z 41.0N  42.5W   75 KT  85 MPH
 72H  03/0600Z 50.5N  29.0W   60 KT  70 MPH...POST-TROP/EXTRATROP
 96H  04/0600Z...ABSORBED BY A FRONTAL ZONE
 
$$
FORECASTER AVILA
 

WTNT41 KNHC 311448
TCDAT1
 
HURRICANE KIRK DISCUSSION NUMBER  12
NWS NATIONAL HURRICANE CENTER MIAMI FL       AL112012
1100 AM AST FRI AUG 31 2012
 
A 1202 UTC SSMIS PASS SHOWED THAT THE SMALL EYE OF KIRK IS STILL
THERE...EVEN THOUGH IT IS NO LONGER APPARENT IN GEOSTATIONARY
IMAGERY. THE INITIAL INTENSITY REMAINS 90 KT BASED ON DVORAK
CI-NUMBERS FROM TAFB AND SAB. WHILE THE GUIDANCE AND THE OFFICIAL
FORECAST NO LONGER SHOW MUCH INTENSIFICATION...IT IS POSSIBLE THAT
KIRK COULD STRENGTHEN A BIT BEFORE THE CYCLONE REACHES COOLER
WATERS AFTER ABOUT 24 HOURS. THE NEW NHC FORECAST HAS BEEN ADJUSTED
DOWNWARD BUT ONLY SHOWS GRADUAL WEAKENING AND KEEPS KIRK AS A
HURRICANE THROUGH 48 HOURS...IN AGREEMENT WITH THE LATEST IVCN
CONSENSUS AID AND THE LGEM. KIRK SHOULD BECOME EXTRATROPICAL BY 72
HOURS AND BE ABSORBED BY A FRONT BY 96 HOURS...ALTHOUGH THIS COULD
OCCUR A BIT SOONER.
 
KIRK IS NOW MOVING A TAD EAST OF NORTH WITH AN INITIAL MOTION
ESTIMATE OF 005/11. THE CYCLONE SHOULD CONTINUE RECURVING AS IT
MOVES AROUND THE WEST SIDE OF THE SUBTROPICAL RIDGE AND THEN
ACCELERATE NORTHEASTWARD ON FRIDAY AHEAD OF A MID-LATITUDE TROUGH.
THE TRACK MODEL GUIDANCE REMAINS IN GOOD AGREEMENT ON THIS
SCENARIO...AND THE NEW NHC TRACK IS CLOSE TO THE PREVIOUS ONE BUT A
BIT SLOWER...TRENDING TOWARD THE LATEST TVCA MULTI-MODEL CONSENSUS.
 
FORECAST POSITIONS AND MAX WINDS
 
INIT  31/1500Z 31.2N  50.8W   90 KT 105 MPH
 12H  01/0000Z 33.1N  50.1W   90 KT 105 MPH
 24H  01/1200Z 35.7N  47.9W   85 KT 100 MPH
 36H  02/0000Z 38.9N  44.4W   80 KT  90 MPH
 48H  02/1200Z 43.0N  39.8W   75 KT  85 MPH
 72H  03/1200Z 53.0N  23.0W   55 KT  65 MPH...POST-TROP/EXTRATROP
 96H  04/1200Z...ABSORBED
 
$$
FORECASTER BRENNAN
 

WTNT41 KNHC 312035
TCDAT1
 
HURRICANE KIRK DISCUSSION NUMBER  13
NWS NATIONAL HURRICANE CENTER MIAMI FL       AL112012
500 PM AST FRI AUG 31 2012
 
KIRK HAS BECOME A LITTLE RAGGED LOOKING IN SATELLITE IMAGERY THIS
AFTERNOON...WITH THE COLDEST CLOUD TOPS NOW DISPLACED TO THE EAST
OF THE CENTER. THIS MAY BE DUE TO SOME UPPER-LEVEL SOUTHWESTERLY
FLOW IMPINGING ON KIRK FROM A MID/UPPER-LEVEL TROUGH SITUATED TO
THE WEST OF THE CYCLONE. A BLEND OF DVORAK CI-NUMBERS FROM TAFB AND
SAB RESULTS IN AN INITIAL INTENSITY OF 80 KT FOR THIS ADVISORY. IT
APPEARS THAT KIRK HAS LIKELY PEAKED IN INTENSITY...ALTHOUGH MOST OF
THE INTENSITY GUIDANCE SUGGESTS ONLY SLOW WEAKENING FOR THE NEXT
DAY OR SO WHILE THE CYCLONE REMAINS OVER RELATIVELY WARM WATERS.
AFTER THAT TIME THE WEAKENING SHOULD BE A LITTLE FASTER BEFORE KIRK
IS ABSORBED BY A FRONT IN ABOUT 72 HOURS. KIRK WILL LIKELY BECOME
POST-TROPICAL BETWEEN THE 48 AND 72 HOUR FORECAST TIMES...BUT THAT
IS NOT SHOWN EXPLICITLY HERE. 

THE INITIAL MOTION ESTIMATE IS 010/11...AS KIRK IS NOW ROUNDING THE
NORTHWEST SIDE OF THE SUBTROPICAL RIDGE. THE GUIDANCE IS IN GOOD
AGREEMENT SHOWING KIRK RECURVING INTO THE MID-LATITUDE FLOW IN THE
NEXT DAY OR SO...AND THE NEW NHC TRACK FORECAST IS LARGELY AN UPDATE
OF THE PREVIOUS ONLY AND IS CLOSE TO THE LATEST MULTI-MODEL
CONSENSUS UNTIL THE CYCLONE IS ABSORBED. 
 
FORECAST POSITIONS AND MAX WINDS
 
INIT  31/2100Z 32.2N  50.2W   80 KT  90 MPH
 12H  01/0600Z 34.3N  49.0W   75 KT  85 MPH
 24H  01/1800Z 37.3N  46.1W   75 KT  85 MPH
 36H  02/0600Z 41.2N  42.1W   70 KT  80 MPH
 48H  02/1800Z 46.0N  36.2W   65 KT  75 MPH
 72H  03/1800Z...ABSORBED
 
$$
FORECASTER BRENNAN
 

WTNT41 KNHC 010237
TCDAT1
 
HURRICANE KIRK DISCUSSION NUMBER  14
NWS NATIONAL HURRICANE CENTER MIAMI FL       AL112012
1100 PM AST FRI AUG 31 2012
 
THE APPEARANCE OF KIRK ON CONVENTIONAL SATELLITE IMAGES HAS BECOME A
LITTLE MORE RAGGED DURING THE LAST SEVERAL HOURS. MICROWAVE
IMAGES...HOWEVER...INDICATE THAT THE STRUCTURE OF THE COMPACT
HURRICANE IS WELL ORGANIZED WITH A PARTIAL EYEWALL STILL INTACT. AN
AVERAGE OF THE LATEST T- AND CI-NUMBERS FROM TAFB...SAB...AND
UW-CIMSS IS THE BASIS FOR LOWERING THE INITIAL INTENSITY TO 70 KT.
KIRK IS FORECAST TO MOVE OVER COOLER WATER DURING THE NEXT DAY OR
SO BUT BECAUSE THE SHEAR IS EXPECTED TO REMAIN RELATIVELY
LOW...ONLY SLOW WEAKENING IS FORECAST DURING THAT TIME PERIOD.
TRANSITION TO AN EXTRATROPICAL CYCLONE IS NOW FORECAST TO OCCUR BY
DAY 2...WHEN KIRK IS EXPECTED TO BE OVER SEA SURFACE TEMPERATURES
WELL BELOW 20C AND IN STRONG SOUTHWESTERLY SHEAR. NEARLY ALL OF THE
MODELS SHOW KIRK BECOMING ABSORBED BY A LARGE-SCALE TROUGH OR
DISSIPATING WITHIN A FEW DAYS.

KIRK IS MOVING TO THE NORTH-NORTHEAST AT A LITTLE FASTER
PACE...015/14...AS IT IS BECOMING MORE EMBEDDED IN THE FLOW TO THE
EAST OF A TROUGH. A TURN TO THE NORTHEAST WITH AN INCREASE IN
FORWARD SPEED IS FORECAST UNTIL KIRK DISSIPATES OR BECOMES ABSORBED. 
THE OFFICIAL FORECAST IS A LITTLE TO THE LEFT OF THE PREVIOUS ONE
AND VERY NEAR THE MULTI-MODEL CONSENSUS...TVCA.

FORECAST POSITIONS AND MAX WINDS
 
INIT  01/0300Z 33.9N  49.5W   70 KT  80 MPH
 12H  01/1200Z 36.1N  47.8W   65 KT  75 MPH
 24H  02/0000Z 39.4N  44.4W   65 KT  75 MPH
 36H  02/1200Z 43.7N  39.6W   60 KT  70 MPH
 48H  03/0000Z 48.1N  33.7W   55 KT  65 MPH...POST-TROP/EXTRATROP
 72H  04/0000Z...ABSORBED
 
$$
FORECASTER CANGIALOSI
 

WTNT41 KNHC 010846
TCDAT1
 
HURRICANE KIRK DISCUSSION NUMBER  15
NWS NATIONAL HURRICANE CENTER MIAMI FL       AL112012
500 AM AST SAT SEP 01 2012
 
MICROWAVE DATA INDICATED THAT THE CENTER OF KIRK WAS EMBEDDED WITHIN
AN AREA OF DEEP CONVECTION. CURRENT SATELLITE IMAGES SUGGEST THAT
THE CENTER IS STILL LOCATED WITHIN THE CONVECTION. BOTH SUBJECTIVE
AND OBJECTIVE SATELLITE INTENSITY ESTIMATES SUPPORT AN INITIAL
INTENSITY OF 65 KNOTS. KIRK WILL BE MOVING OVER COOLER SEA SURFACE
TEMPERATURES AND STRONG SHEAR IN ABOUT A DAY.  MOST LIKELY...THE
CYCLONE WILL BECOME POST-TROPICAL IN 36 HOURS OR LESS BEFORE IT IS
ABSORBED BY A FRONTAL SYSTEM.  

THE HURRICANE IS MOVING TOWARD THE NORTHEAST OR 035 DEGREES AT 20
KNOTS...EMBEDDED IN THE SOUTHWEST FLOW AHEAD OF A LARGE
MIDDLE-LEVEL TROUGH.  THE CYCLONE WILL CONTINUE ON THE SAME GENERAL
TRACK WITH AN INCREASE IN FORWARD SPEED AS THE TROUGH TO THE WEST
AMPLIFIES. MODELS ARE IN VERY GOOD AGREEMENT...AND THE NHC FORECAST
IS VERY CLOSE TO THE CONSENSUS.
  
 
FORECAST POSITIONS AND MAX WINDS
 
INIT  01/0900Z 35.3N  48.2W   65 KT  75 MPH
 12H  01/1800Z 37.7N  46.0W   60 KT  70 MPH
 24H  02/0600Z 41.5N  42.0W   50 KT  60 MPH
 36H  02/1800Z 46.0N  36.0W   40 KT  45 MPH...POST-TROP/EXTRATROP
 48H  03/0600Z...ABSORBED BY A FRONTAL SYSTEM
 
$$
FORECASTER AVILA
 

WTNT41 KNHC 011444
TCDAT1
 
TROPICAL STORM KIRK DISCUSSION NUMBER  16
NWS NATIONAL HURRICANE CENTER MIAMI FL       AL112012
1100 AM AST SAT SEP 01 2012
 
SATELLITE IMAGERY SHOWS THAT THE CLOUD PATTERN OF KIRK IS BECOMING
ELONGATED TOWARD THE NORTHEAST...WHILE RECENT MICROWAVE IMAGERY
SHOWS THE LOW-LEVEL CENTER IS LOCATED NORTHWEST OF THE CLODEST
CLOUD TOPS. THIS IS LIKELY DUE TO STRONG SOUTHWESTERLY UPPER-LEVEL
FLOW BEGINNING TO IMPINGE ON THE CYCLONE. THE INITIAL INTENSITY IS
DECREASED TO 60 KT FOR THIS ADVISORY...TRENDING TOWARD THE LATEST
DVORAK CI-NUMBER FROM SAB. INCREASING SHEAR AND RAPIDLY COOLING
SSTS ALONG THE TRACK IN THE NEXT DAY OR SO SHOULD CONTRIBUTE TO
FURTHER WEAKENING AS THE CYCLONE BECOMES POST-TROPICAL IN ABOUT 36
HOURS. BY 48 HOURS...KIRK IS EXPECTED TO BE ABSORBED BY AN
APPROACHING FRONT OVER THE NORTH ATLANTIC.

THE INITIAL MOTION ESTIMATE IS 035/22...A LITTLE FASTER THAN BEFORE.
THE NEW NHC TRACK IS A LITTLE TO THE LEFT OF THE PREVIOUS ONE DUE TO
THE INITIAL POSITION. OTHERWISE...THERE IS LITTLE CHANGE TO THE
FORECAST REASONING AND THE OFFICIAL FORECAST IS CLOSE TO THE
MULTI-MODEL CONSENSUS SHOWING A NORTHEASTWARD MOTION AT AN
INCREASING FORWARD SPEED UNTIL THE CYCLONE IS ABSORBED.
 
THE INITIAL 34-KT AND 50-KT WIND RADII WERE ADJUSTED BASED ON A 1238
UTC ASCAT PASS. 
 
FORECAST POSITIONS AND MAX WINDS
 
INIT  01/1500Z 37.4N  46.5W   60 KT  70 MPH
 12H  02/0000Z 40.0N  43.8W   55 KT  65 MPH
 24H  02/1200Z 44.3N  39.0W   50 KT  60 MPH
 36H  03/0000Z 49.5N  32.0W   40 KT  45 MPH...POST-TROP/EXTRATROP
 48H  03/1200Z...ABSORBED
 
$$
FORECASTER BRENNAN
 

WTNT41 KNHC 012037
TCDAT1
 
TROPICAL STORM KIRK DISCUSSION NUMBER  17
NWS NATIONAL HURRICANE CENTER MIAMI FL       AL112012
500 PM AST SAT SEP 01 2012

THE SATELLITE PRESENTATION OF KIRK CONTINUES TO DETERIORATE. CLOUD
TOP TEMPERATURES HAVE WARMED AND THE CONVECTIVE OVERCAST CONTINUES
TO ELONGATE NORTHEASTWARD AS SOUTHWESTERLY UPPER-LEVEL WINDS AFFECT
THE CYCLONE. THE INITIAL INTENSITY OF 55 KT IS CLOSE TO THE LATEST
ADT ESTIMATE FROM UW-CIMSS AND THE DVORAK FINAL-T NUMBER FROM TAFB.
AS KIRK MOVES OVER COOL WATERS AND THE SHEAR INCREASES MARKEDLY...
THE CYCLONE IS EXPECTED TO BECOME POST-TROPICAL IN ABOUT 24 HOURS.
KIRK SHOULD BE ABSORBED BY A FRONT BY 36 HOURS.

THE INITIAL MOTION ESTIMATE IS 035/25...AS KIRK CONTINUES TO
ACCELERATE NORTHEASTWARD AHEAD OF A MID-LATITUDE TROUGH. THE NEW
NHC FORECAST IS LARGELY AN UPDATE OF THE PREVIOUS ONE AND IS A
LITTLE FASTER BY 24 HOURS...TRENDING TOWARD THE LATEST MULTI-MODEL
CONSENSUS. 
 
FORECAST POSITIONS AND MAX WINDS
 
INIT  01/2100Z 39.5N  44.3W   55 KT  65 MPH
 12H  02/0600Z 42.4N  41.1W   55 KT  65 MPH
 24H  02/1800Z 47.6N  34.7W   45 KT  50 MPH...POST-TROPICAL
 36H  03/0600Z...ABSORBED
 
$$
FORECASTER BRENNAN
 

WTNT41 KNHC 020255
TCDAT1
 
TROPICAL STORM KIRK DISCUSSION NUMBER  18
NWS NATIONAL HURRICANE CENTER MIAMI FL       AL112012
1100 PM AST SAT SEP 01 2012
 
DEEP CONVECTION ASSOCIATED WITH KIRK HAS BEEN STEADILY SHRINKING
OVER THE PAST SEVERAL HOURS AND NOW ONLY CONSISTS OF A FEW PATCHES.
AN AVERAGE OF THE LATEST CI-NUMBERS FROM TAFB...SAB...AND UW-CIMSS
SUPPORT LOWERING THE INITIAL WIND SPEED TO 50 KT...AND THAT COULD
BE GENEROUS. KIRK IS FORECAST TO BECOME A POST-TROPICAL CYCLONE ON
SUNDAY AS IT MOVES OVER WATERS COLDER THAN 20C AND INTO
SOUTHWESTERLY SHEAR OF MORE THAN 30 KT. THE SMALL CYCLONE IS
EXPECTED TO BE ABSORBED SUNDAY NIGHT BY A COLD FRONT THAT IS
CURRENTLY SITUATED ABOUT 500 N MI TO ITS NORTHWEST. THE INTENSITY
AND WIND RADII FORECASTS CLOSELY FOLLOW THE GUIDANCE PROVIDED BY
THE NOAA OCEAN PREDICTION CENTER.
 
THE TROPICAL STORM IS MOVING QUICKLY NORTHEASTWARD AT ABOUT 25 KT AS
IT IS WELL EMBEDDED IN THE STRONG FLOW TO THE EAST OF A TROUGH.
A CONTINUED NORTHEASTWARD MOTION WITH AN INCREASE IN FORWARD SPEED
IS EXPECTED UNTIL KIRK IS ABSORBED BY THE AFOREMENTIONED FRONT.
 
FORECAST POSITIONS AND MAX WINDS
 
INIT  02/0300Z 41.2N  41.8W   50 KT  60 MPH
 12H  02/1200Z 44.5N  38.0W   40 KT  45 MPH...POST-TROPICAL
 24H  03/0000Z 50.0N  30.2W   40 KT  45 MPH...POST-TROPICAL
 36H  03/1200Z...DISSIPATED
 
$$
FORECASTER CANGIALOSI
 

WTNT41 KNHC 020845
TCDAT1
 
TROPICAL STORM KIRK DISCUSSION NUMBER  19
NWS NATIONAL HURRICANE CENTER MIAMI FL       AL112012
500 AM AST SUN SEP 02 2012
 
KIRK HAS BEEN ACCELERATING OVER THE PAST SEVERAL HOURS AS IT
CONTINUES ITS TREK ACROSS THE FAR NORTH ATLANTIC. THE INITIAL
MOTION ESTIMATE IS NOW 045/28 KT. CONTINUED ACCELERATION TOWARD 
THE NORTHEAST IS EXPECTED FOR THE NEXT 36 HOURS NOW THAT THE CYCLONE
IS CAUGHT UP IN DEEP SOUTHWESTERLY FLOW AHEAD OF A DEEPENING
MID-TROPOSPHERIC TROUGH THAT IS MOVING EASTWARD ACROSS THE CANADIAN
MARITIMES REGION. SINCE KIRK REMAINS ON TRACK...THE OFFICIAL
FORECAST IS JUST AN EXTENSION OF THE PREVIOUS ADVISORY TRACK AND IS
VERY CLOSE TO THE TV15 AND TVCA CONSENSUS MODELS.

A SMALL FLARE UP OF DEEP CONVECTION HAS DEVELOPED OVER THE CENTER OF
KIRK DURING THE PAST 6 HOURS...WHICH HAS HELPED KIRK TO CLING ON TO
TROPICAL CYCLONE STATUS.  HOWEVER...THIS WILL LIKELY BE A
SHORT-LIVED RESPITE...AND WEAKENING SHOULD RESUME LATER TODAY AS
THE CYCLONE MOVES OVER SUB-20C SSTS IN 6-12 HOURS. DEGENERATION
INTO A POST-TROPICAL REMNANT LOW IS EXPECTED TO OCCUR BY 12
HOURS...AND THE LOW IS FORECAST TO BE ABSORBED BY A FRONTAL SYSTEM
BY 36 HOURS...IF NOT SOONER. THE INTENSITY AND WIND RADII FORECASTS
CLOSELY FOLLOW THE GUIDANCE PROVIDED BY THE NOAA OCEAN PREDICTION
CENTER.
 
FORECAST POSITIONS AND MAX WINDS
 
INIT  02/0900Z 43.5N  39.2W   45 KT  50 MPH
 12H  02/1800Z 47.4N  34.1W   40 KT  45 MPH...POST-TROPICAL
 24H  03/0600Z 53.0N  25.0W   40 KT  45 MPH...POST-TROPICAL
 36H  03/1800Z...ABSORBED BY FRONTAL SYSTEM
 
$$
FORECASTER STEWART
 

WTNT41 KNHC 021450
TCDAT1
 
TROPICAL STORM KIRK DISCUSSION NUMBER  20
NWS NATIONAL HURRICANE CENTER MIAMI FL       AL112012
1100 AM AST SUN SEP 02 2012

KIRK IS NOT EXPECTED TO LIVE LONG AND PROSPER. VISIBLE SATELLITE
IMAGES AND A 1214 UTC ASCAT PASS INDICATE THAT THE SYSTEM STILL HAS
A CLOSED CIRCULATION BUT IT IS BECOMING ELONGATED. MAXIMUM
RELIABLE WINDS IN THE ASCAT PASS WERE AROUND 45 KT SO THE INITIAL
WIND SPEED IS HELD AT THAT VALUE. KIRK WILL LIKELY BECOME
POST-TROPICAL LATER TODAY OR DISSIPATE JUST BEFORE IT MERGES WITH A
FRONT THAT IS CURRENTLY LOCATED ABOUT 200 N MI TO ITS WEST. 

CONVENTIONAL SATELLITE AND MICROWAVE DATA INDICATE THAT KIRK HAS
BEEN MOVING A LITTLE TO THE LEFT OF THE PREVIOUS TRACK...WITH THE
LATEST INITIAL MOTION ESTIMATE BEING A VERY FAST 035/32. AN EVEN
FASTER NORTHEASTWARD MOTION IS FORECAST UNTIL THE CYCLONE BECOMES
ABSORBED BY THE FRONT TONIGHT OR EARLY MONDAY.

THE 34-KT WIND RADII WERE MODIFIED BASED ON THE AFOREMENTIONED ASCAT
PASS.
 
FORECAST POSITIONS AND MAX WINDS
 
INIT  02/1500Z 46.2N  36.5W   45 KT  50 MPH
 12H  03/0000Z 51.1N  30.1W   45 KT  50 MPH...POST-TROPICAL
 24H  03/1200Z...DISSIPATED
 
$$
FORECASTER CANGIALOSI
 

