WTNT44 KNHC 021456 RRA

TCDAT4



HURRICANE MATTHEW DISCUSSION NUMBER  18

NWS NATIONAL HURRICANE CENTER MIAMI FL       AL142016

1100 AM EDT SUN OCT 02 2016



THE EYE OF MATTHEW HAS BECOME OBSCURED ON VISIBLE SATELLITE IMAGES,

WHICH IS OFTEN AN INDICATION OF WEAKENING.  MICROWAVE IMAGES SHOWED

A DISTINCT DRY SLOT OVER THE SOUTHWESTERN AND WESTERN PORTIONS OF

THE CIRCULATION.  ALSO THERE HAS BEEN A PERSISTENT, BUT

INEXPLICABLE, CLUSTER OF DEEP CONVECTION LOCATED A COUPLE OF DEGREES

TO THE EAST OF THE HURRICANE AND THE EFFECT OF THIS FEATURE ON

MATTHEW'S INTENSITY EVOLUTION IS UNKNOWN.  AN AIR FORCE HURRICANE

HUNTER AIRCRAFT INVESTIGATED THE NORTHEASTERN EYEWALL, THE STRONGEST

PART OF THE CIRCULATION, AND FOUND THAT THE WINDS HAD DECREASED

SOMEWHAT FROM EARLIER THIS MORNING.  THE INTENSITY IS SET TO 120 KT

FOR THIS ADVISORY.  THE VERTICAL SHEAR IS NOT FORECAST TO BECOME

MUCH STRONGER WHILE MATTHEW IS IN THE CARIBBEAN, SO THE HURRICANE

SHOULD REMAIN NEAR CATEGORY 4 STATUS FOR THE NEXT 36-48 HOURS.  ONCE

MATTHEW MOVES INTO THE ATLANTIC, SOME INCREASE IN SHEAR ALONG WITH

A DECREASE IN OCEANIC HEAT CONTENT SHOULD RESULT IN A LITTLE

WEAKENING.  HOWEVER, THERE IS SIGNIFICANT UNCERTAINTY IN THE 3-5 DAY

FORECAST INTENSITIES.



AFTER A NORTHWESTWARD MOTION, THE CENTER HAS MEANDERED WESTWARD

OVER THE PAST FEW HOURS.  MATTHEW IS EXPECTED TO TURN NORTHWARD AND

MOVE BETWEEN A MID-LEVEL RIDGE TO THE EAST AND A WEAK TROUGH OVER

THE GULF OF MEXICO FOR THE NEXT FEW DAYS.  LATER IN THE FORECAST

PERIOD, THE GLOBAL MODELS SHOW A SLIGHT BUILDING OF A RIDGE TO THE

NORTHEAST OF MATTHEW WHICH WOULD INDUCE A TURN TOWARD THE LEFT IN

3-5 DAYS.  THE TIMING AND MAGNITUDE OF THIS TURN IS STILL UNCERTAIN=