Issued at 1100 PM AST WED SEP 26 2012
000
WTNT44 KNHC 270249
TCDAT4
TROPICAL STORM NADINE DISCUSSION NUMBER 58
NWS NATIONAL HURRICANE CENTER MIAMI FL AL142012
1100 PM AST WED SEP 26 2012
THE SATELLITE PRESENTATION OF NADINE HAS NOT CHANGED MUCH OVER THE
PAST SEVERAL HOURS. DEEP CONVECTION REMAINS LIMITED TO A BAND
CURVING AROUND THE EASTERN SEMICIRCLE OF THE TROPICAL CYCLONE.
SATELLITE INTENSITY ESTIMATES FROM TAFB AND SAB...AS WELL AS
DROPSONDE DATA FROM THE NASA GLOBAL HAWK...SUPPORT HOLDING THE
INITIAL INTENSITY AT 45 KT. WHILE DRY AIR CONTINUES TO SURROUND
NADINE...THE TROPICAL STORM IS MOVING INTO AN AREA OF WARMER SEA
SURFACE TEMPERATURES...AND THE VERTICAL WIND SHEAR IS EXPECTED TO
REMAIN LIGHT ENOUGH TO ALLOW FOR SOME SLOW STRENGTHENING OVER THE
NEXT 36-48 HOURS. AFTER THAT...STRONGER SHEAR AND COOLER SEA
SURFACE TEMPERATURES SHOULD TO LEAD TO WEAKENING. THE NHC FORECAST
FOLLOWS THE LGEM MODEL AND IS CLOSE TO THE PREVIOUS ADVISORY.
NADINE CONTINUES TO MOVE TO THE SOUTHWEST AROUND A DEEP LAYER RIDGE
LOCATED OVER THE CENTRAL ATLANTIC...AND THE LONG-TERM MOTION
ESTIMATE IS 220/5. THE DYNAMICAL MODEL GUIDANCE REMAINS IN GOOD
AGREEMENT THAT NADINE WILL MOVE AROUND THE PERIPHERY OF THE RIDGE
FOR THE NEXT SEVERAL DAYS. BY DAY 4...THE RIDGE IS EXPECTED TO MOVE
AWAY FROM THE TROPICAL CYCLONE...WHICH SHOULD RESULT IN FAIRLY WEAK
ENVIRONMENTAL STEERING CONDITIONS. THE MODEL SPREAD INCREASES
SUBSTANTIALLY AT THIS POINT...WITH THE GFS CONTINUING TO SUGGEST A
SLOW EASTWARD MOTION WHILE THE ECMWF SHOWS A TURN TOWARD THE
WEST OR SOUTHWEST. THE OFFICIAL FORECAST SPLITS THESE TWO
SOLUTIONS...AND LIES NEAR THE CONSENSUS MODELS IV15 AND FSSE.
THE WIND RADII WERE ADJUSTED BASED ON A 2338 ASCAT PASS.
FORECAST POSITIONS AND MAX WINDS
INIT 27/0300Z 29.5N 31.4W 45 KT 50 MPH
12H 27/1200Z 28.8N 32.2W 45 KT 50 MPH
24H 28/0000Z 28.6N 33.6W 50 KT 60 MPH
36H 28/1200Z 29.1N 34.8W 50 KT 60 MPH
48H 29/0000Z 30.0N 35.8W 55 KT 65 MPH
72H 30/0000Z 33.0N 36.8W 50 KT 60 MPH
96H 01/0000Z 35.5N 37.5W 50 KT 60 MPH
120H 02/0000Z 36.0N 37.5W 45 KT 50 MPH
$$
FORECASTER AVILA/ZELINSKY
Continue reading...
000
WTNT44 KNHC 270249
TCDAT4
TROPICAL STORM NADINE DISCUSSION NUMBER 58
NWS NATIONAL HURRICANE CENTER MIAMI FL AL142012
1100 PM AST WED SEP 26 2012
THE SATELLITE PRESENTATION OF NADINE HAS NOT CHANGED MUCH OVER THE
PAST SEVERAL HOURS. DEEP CONVECTION REMAINS LIMITED TO A BAND
CURVING AROUND THE EASTERN SEMICIRCLE OF THE TROPICAL CYCLONE.
SATELLITE INTENSITY ESTIMATES FROM TAFB AND SAB...AS WELL AS
DROPSONDE DATA FROM THE NASA GLOBAL HAWK...SUPPORT HOLDING THE
INITIAL INTENSITY AT 45 KT. WHILE DRY AIR CONTINUES TO SURROUND
NADINE...THE TROPICAL STORM IS MOVING INTO AN AREA OF WARMER SEA
SURFACE TEMPERATURES...AND THE VERTICAL WIND SHEAR IS EXPECTED TO
REMAIN LIGHT ENOUGH TO ALLOW FOR SOME SLOW STRENGTHENING OVER THE
NEXT 36-48 HOURS. AFTER THAT...STRONGER SHEAR AND COOLER SEA
SURFACE TEMPERATURES SHOULD TO LEAD TO WEAKENING. THE NHC FORECAST
FOLLOWS THE LGEM MODEL AND IS CLOSE TO THE PREVIOUS ADVISORY.
NADINE CONTINUES TO MOVE TO THE SOUTHWEST AROUND A DEEP LAYER RIDGE
LOCATED OVER THE CENTRAL ATLANTIC...AND THE LONG-TERM MOTION
ESTIMATE IS 220/5. THE DYNAMICAL MODEL GUIDANCE REMAINS IN GOOD
AGREEMENT THAT NADINE WILL MOVE AROUND THE PERIPHERY OF THE RIDGE
FOR THE NEXT SEVERAL DAYS. BY DAY 4...THE RIDGE IS EXPECTED TO MOVE
AWAY FROM THE TROPICAL CYCLONE...WHICH SHOULD RESULT IN FAIRLY WEAK
ENVIRONMENTAL STEERING CONDITIONS. THE MODEL SPREAD INCREASES
SUBSTANTIALLY AT THIS POINT...WITH THE GFS CONTINUING TO SUGGEST A
SLOW EASTWARD MOTION WHILE THE ECMWF SHOWS A TURN TOWARD THE
WEST OR SOUTHWEST. THE OFFICIAL FORECAST SPLITS THESE TWO
SOLUTIONS...AND LIES NEAR THE CONSENSUS MODELS IV15 AND FSSE.
THE WIND RADII WERE ADJUSTED BASED ON A 2338 ASCAT PASS.
FORECAST POSITIONS AND MAX WINDS
INIT 27/0300Z 29.5N 31.4W 45 KT 50 MPH
12H 27/1200Z 28.8N 32.2W 45 KT 50 MPH
24H 28/0000Z 28.6N 33.6W 50 KT 60 MPH
36H 28/1200Z 29.1N 34.8W 50 KT 60 MPH
48H 29/0000Z 30.0N 35.8W 55 KT 65 MPH
72H 30/0000Z 33.0N 36.8W 50 KT 60 MPH
96H 01/0000Z 35.5N 37.5W 50 KT 60 MPH
120H 02/0000Z 36.0N 37.5W 45 KT 50 MPH
$$
FORECASTER AVILA/ZELINSKY
Continue reading...