Issued at 1100 PM AST FRI SEP 13 2013
000
WTNT44 KNHC 140256
TCDAT4
TROPICAL STORM HUMBERTO DISCUSSION NUMBER 22
NWS NATIONAL HURRICANE CENTER MIAMI FL AL092013
1100 PM AST FRI SEP 13 2013
ALTHOUGH HUMBERTO HAS BEEN DEVOID OF DEEP CONVECTION FOR MORE THAN
10 HOURS...A 13/2307Z ASCAT-B OVERPASS INDICATED WINDS OF 37-38 KT
NORTH OF THE CENTER...WHILE MISSING THE EASTERN SEMICIRCLE WHERE
STRONGER WINDS COULD HAVE BEEN PRESENT. THEREFORE THE INTENSITY IS
ONLY LOWERED TO 40 KT AND THE SYSTEM IS BEING MAINTAINED AS A
TROPICAL CYCLONE FOR ONE MORE ADVISORY CYCLE. HOWEVER...INCREASING
VERTICAL WIND SHEAR IN EXCESS OF 40 KT ALONG WITH SUB-26C SSTS
SHOULD COMBINE TO CAUSE HUMBERTO TO DEGENERATE INTO A NON-CONVECTIVE
POST-TROPICAL CYCLONE WITHIN THE NEXT 6-12 HOURS. HUMBERTO IS THEN
FORECAST TO REMAIN A REMNANT LOW FOR ABOUT 60-72 HOURS...AT WHICH
TIME THE SHEAR IS FORECAST TO DECREASE SHARPLY WHILE THE SYSTEM IS
MOVING OVER 28C SSTS. THIS SHOULD ALLOW FOR REGENERATION BACK INTO
A TROPICAL CYCLONE BY DAY 3...WITH HUMBERTO POSSIBLY REGAINING
HURRICANE STRENGTH BY DAY 5. THE INTENSITY FORECAST CLOSELY FOLLOWS
THE STATISTICAL-DYNAMICAL MODELS AND THE TREND OF THE GLOBAL
MODELS...ESPECIALLY AT DAYS 3-5.
THE INITIAL MOTION ESTIMATE IS 270/08 KT. THERE REMAINS NO
SIGNIFICANT CHANGE TO THE PREVIOUS TRACK FORECAST OR SYNOPTIC
REASONING. HUMBERTO SHOULD BE STEERED WESTWARD TO WEST-
NORTHWESTWARD BY A STRONG RIDGE TO ITS NORTH...AND THEN GRADUALLY
RECURVE INTO THE MID-LATITUDE WESTERLIES BY DAYS 3/4 AS A STRONG
MID/UPPER-LEVEL TROUGH AND ASSOCIATED COLD FRONT MOVE OFF OF THE
U.S. EAST COAST. THE OFFICIAL FORECAST TRACK IS SIMILAR TO THE
PREVIOUS ADVISORY AND CLOSELY FOLLOWS THE MULTI-MODEL CONSENSUS
TVCA.
FORECAST POSITIONS AND MAX WINDS
INIT 14/0300Z 24.8N 33.0W 40 KT 45 MPH
12H 14/1200Z 25.4N 34.8W 35 KT 40 MPH...POST-TROPICAL
24H 15/0000Z 26.3N 37.2W 30 KT 35 MPH...POST-TROP/REMNT LOW
36H 15/1200Z 27.2N 39.3W 30 KT 35 MPH...POST-TROP/REMNT LOW
48H 16/0000Z 28.2N 41.1W 30 KT 35 MPH...POST-TROP/REMNT LOW
72H 17/0000Z 30.3N 43.7W 35 KT 40 MPH
96H 18/0000Z 32.6N 45.1W 50 KT 60 MPH
120H 19/0000Z 36.5N 43.5W 65 KT 75 MPH
$$
FORECASTER STEWART
Continue reading...
000
WTNT44 KNHC 140256
TCDAT4
TROPICAL STORM HUMBERTO DISCUSSION NUMBER 22
NWS NATIONAL HURRICANE CENTER MIAMI FL AL092013
1100 PM AST FRI SEP 13 2013
ALTHOUGH HUMBERTO HAS BEEN DEVOID OF DEEP CONVECTION FOR MORE THAN
10 HOURS...A 13/2307Z ASCAT-B OVERPASS INDICATED WINDS OF 37-38 KT
NORTH OF THE CENTER...WHILE MISSING THE EASTERN SEMICIRCLE WHERE
STRONGER WINDS COULD HAVE BEEN PRESENT. THEREFORE THE INTENSITY IS
ONLY LOWERED TO 40 KT AND THE SYSTEM IS BEING MAINTAINED AS A
TROPICAL CYCLONE FOR ONE MORE ADVISORY CYCLE. HOWEVER...INCREASING
VERTICAL WIND SHEAR IN EXCESS OF 40 KT ALONG WITH SUB-26C SSTS
SHOULD COMBINE TO CAUSE HUMBERTO TO DEGENERATE INTO A NON-CONVECTIVE
POST-TROPICAL CYCLONE WITHIN THE NEXT 6-12 HOURS. HUMBERTO IS THEN
FORECAST TO REMAIN A REMNANT LOW FOR ABOUT 60-72 HOURS...AT WHICH
TIME THE SHEAR IS FORECAST TO DECREASE SHARPLY WHILE THE SYSTEM IS
MOVING OVER 28C SSTS. THIS SHOULD ALLOW FOR REGENERATION BACK INTO
A TROPICAL CYCLONE BY DAY 3...WITH HUMBERTO POSSIBLY REGAINING
HURRICANE STRENGTH BY DAY 5. THE INTENSITY FORECAST CLOSELY FOLLOWS
THE STATISTICAL-DYNAMICAL MODELS AND THE TREND OF THE GLOBAL
MODELS...ESPECIALLY AT DAYS 3-5.
THE INITIAL MOTION ESTIMATE IS 270/08 KT. THERE REMAINS NO
SIGNIFICANT CHANGE TO THE PREVIOUS TRACK FORECAST OR SYNOPTIC
REASONING. HUMBERTO SHOULD BE STEERED WESTWARD TO WEST-
NORTHWESTWARD BY A STRONG RIDGE TO ITS NORTH...AND THEN GRADUALLY
RECURVE INTO THE MID-LATITUDE WESTERLIES BY DAYS 3/4 AS A STRONG
MID/UPPER-LEVEL TROUGH AND ASSOCIATED COLD FRONT MOVE OFF OF THE
U.S. EAST COAST. THE OFFICIAL FORECAST TRACK IS SIMILAR TO THE
PREVIOUS ADVISORY AND CLOSELY FOLLOWS THE MULTI-MODEL CONSENSUS
TVCA.
FORECAST POSITIONS AND MAX WINDS
INIT 14/0300Z 24.8N 33.0W 40 KT 45 MPH
12H 14/1200Z 25.4N 34.8W 35 KT 40 MPH...POST-TROPICAL
24H 15/0000Z 26.3N 37.2W 30 KT 35 MPH...POST-TROP/REMNT LOW
36H 15/1200Z 27.2N 39.3W 30 KT 35 MPH...POST-TROP/REMNT LOW
48H 16/0000Z 28.2N 41.1W 30 KT 35 MPH...POST-TROP/REMNT LOW
72H 17/0000Z 30.3N 43.7W 35 KT 40 MPH
96H 18/0000Z 32.6N 45.1W 50 KT 60 MPH
120H 19/0000Z 36.5N 43.5W 65 KT 75 MPH
$$
FORECASTER STEWART
Continue reading...