000
WTPZ45 KNHC 080248
TCDEP5
 
TROPICAL STORM JOVA DISCUSSION NUMBER   9
NWS NATIONAL HURRICANE CENTER MIAMI FL       EP102011
800 PM PDT FRI OCT 07 2011

SATELLITE IMAGERY THIS EVENING SHOWS THAT JOVA REMAINS A SHEARED
SYSTEM...WITH THE LOW-LEVEL CENTER ON THE NORTHERN EDGE OF THE MAIN
CONVECTIVE MASS.  ANALYSES FROM THE SHIPS MODEL AND CIMSS AT THE
UNIVERSITY OF WISCONSIN ARE SHOWING ABOUT 10 KT OF NORTHEASTERLY
VERTICAL WIND SHEAR.  THE SATELLITE INTENSITY ESTIMATES AND THE
ORGANIZATION ARE UNCHANGED SINCE THE PREVIOUS ADVISORY...SO THE
INITIAL INTENSITY REMAINS 55 KT.

JOVA IS GRADUALLY TURNING NORTHWARD...WITH THE INITIAL MOTION NOW
350/7.  WATER VAPOR IMAGERY SHOWS A LARGE MID/UPPER-LEVEL TROUGH
COVERING THE PACIFIC NORTH OF 20N EAST OF 130W.  THE DYNAMICAL
MODELS FORECAST THIS FEATURE TO WEAKEN DURING THE NEXT 3-4 DAYS. 
HOWEVER...ENOUGH TROUGHING IS FORECAST TO REMAIN IN THE AREA TO
SLOWLY STEER JOVA IN A GENERAL NORTHEASTERLY DIRECTION.  THIS MOTION
SHOULD BRING THE CENTER NEAR OR OVER THE SOUTHWESTERN COAST OF
MEXICO IN 3-4 DAYS TIME.  THE TRACK GUIDANCE IS IN GOOD AGREEMENT
ON THE DIRECTION OF MOTION...ALTHOUGH THERE IS A SPREAD IN THE
FORWARD SPEED AND LANDFALL TIME BETWEEN THE FASTER GFS-BASED
GUIDANCE AND THE SLOWER ECMWF/UKMET/NOGAPS MODELS.  THE NEW
FORECAST TRACK IS SIMILAR TO THE PREVIOUS TRACK...WITH THE CENTER
NEAR THE COAST OF MEXICO AT 72 HOURS AND WELL INLAND AT 96 HOURS.

THE DYNAMICAL MODELS FORECAST THE CURRENT SHEAR TO ABATE DURING THE
NEXT 12-24 HOURS.  IF THIS VERIFIES...JOVA SHOULD START TO
STRENGTHEN...AND THE INTENSITY GUIDANCE SUGGESTS THE SYSTEM SHOULD
REACH HURRICANE STRENGTH IN 24 HOURS OR SO.  THIS IS REFLECTED IN
THE INTENSITY FORECAST.  AFTER THAT TIME...THERE IS SOME DIVERGENCE
IN THE INTENSITY FORECAST MODELS.  THE SHIPS AND LGEM MODELS
FORECAST JOVA TO REACH A PEAK INTENSITY OF 65-75 KT BEFORE
LANDFALL...WHILE THE HWRF AND GFDL FORECAST THE CYCLONE TO BECOME A
MAJOR HURRICANE.  THE SHIPS MODEL DIAGNOSTICS SHOW LIGHT SHEAR FROM
24-72 HOURS...SO IT IS UNCLEAR WHY SHIPS AND LGEM DO NOT SHOW MORE
STRENGTHENING.  THE NEW INTENSITY FORECAST IS SIMILAR TO THE
PREVIOUS FORECAST...CALLING FOR JOVA TO BECOME A MAJOR HURRICANE
BEFORE LANDFALL IN MEXICO.  AFTER LANDFALL...JOVA SHOULD QUICKLY
WEAKEN AND DISSIPATE OVER THE MOUNTAINS OF CENTRAL MEXICO.

FORECAST POSITIONS AND MAX WINDS
 
INIT  08/0300Z 15.3N 110.6W   55 KT  65 MPH
 12H  08/1200Z 15.9N 110.5W   60 KT  70 MPH
 24H  09/0000Z 16.4N 109.6W   70 KT  80 MPH
 36H  09/1200Z 16.9N 108.4W   80 KT  90 MPH
 48H  10/0000Z 17.4N 107.4W   90 KT 105 MPH
 72H  11/0000Z 19.0N 105.5W  105 KT 120 MPH
 96H  12/0000Z 21.5N 103.5W   30 KT  35 MPH...INLAND
120H  13/0000Z...DISSIPATED
 
$$
FORECASTER BEVEN