WTPZ42 KNHC 120234 RRA

TCDEP2



TROPICAL STORM JOVA DISCUSSION NUMBER   1

NWS NATIONAL HURRICANE CENTER MIAMI FL       EP122017

900 PM MDT FRI AUG 11 2017



THE MID-LEVEL REMNANTS OF ATLANTIC HURRICANE FRANKLIN MOVED ACROSS

MEXICO DURING THE PAST DAY OR SO AND INDUCED A SURFACE CIRCULATION

EARLY THIS MORNING NEAR THE SOUTHWEST COAST OF MEXICO. WHILE EARLIER

IT WAS DIFFICULT TO SEE A WELL-DEFINED CENTER, SATELLITE IMAGES

SUGGEST THAT THE MULTIPLE SWIRLS SEEN IN VISIBLE IMAGERY DURING

MIDDAY HAVE CONSOLIDATED, WITH ENOUGH CONVECTION REMAINING TO

CLASSIFY THE SYSTEM AS A TROPICAL CYCLONE. THE INITIAL WIND SPEED IS

35 KT BASED ON DATA FROM SHIP WDF4764 AND A CENTRAL PRESSURE

ESTIMATE OF 1003 MB, MAKING THIS SYSTEM THE TENTH TROPICAL STORM OF

THE SEASON.  ALTHOUGH THIS IS THE FIRST TROPICAL STORM TO FORM IN

THE BASIN IN ABOUT 3 WEEKS, THE EASTERN PACIFIC IS STILL WAY AHEAD

OF SCHEDULE SINCE THE AVERAGE TENTH TROPICAL STORM FORMS ON AUGUST

31.



JOVA IS OVER VERY WARM WATER BUT IS MODERATELY SHEARED FROM THE

NORTHEAST DUE TO THE LARGE HIGH OVER MEXICO.   THE STORM HAS ABOUT A

DAY TO POTENTIALLY INTENSIFY BEFORE A COMBINATION OF COOLER WATERS

AND INCREASING NORTHEASTERLY SHEAR LIKELY START A WEAKENING TREND.

MOST OF GUIDANCE RESPOND TO THIS ENVIRONMENT BY SHOWING LITTLE

CHANGE TOMORROW, AND A SLOW WEAKENING STARTING BY SUNDAY.  JOVA IS

FORECAST TO BECOME A REMNANT LOW BY MONDAY DUE TO MARGINAL WATER

TEMPERATURES AND CONTINUED ENTRAINMENT OF DRY STABLE AIR.  THE

OFFICIAL FORECAST IS CLOSE TO A BLEND OF SHIPS/LGEM IN THE SHORT

TERM, AND THE INTENSITY CONSENSUS IN THE LONG TERM.



THE INITIAL MOTION IS 285/12.  A MID-LEVEL RIDGE BUILDING WESTWARD