000
AXNT20 KNHC 170000
TWDAT

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
805 PM EDT WED JUL 16 2014

TROPICAL WEATHER DISCUSSION FOR NORTH AMERICA...CENTRAL
AMERICA...GULF OF MEXICO...CARIBBEAN SEA...NORTHERN SECTIONS OF
SOUTH AMERICA...AND ATLANTIC OCEAN TO THE AFRICAN COAST FROM THE
EQUATOR TO 32N. THE FOLLOWING INFORMATION IS BASED ON SATELLITE
IMAGERY...WEATHER OBSERVATIONS...RADAR...AND METEOROLOGICAL
ANALYSIS.

BASED ON 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH
2345 UTC.

...TROPICAL WAVES...
TROPICAL WAVE HAS COME OFF THE WEST AFRICAN COAST EARLIER THIS
AFTERNOON. ITS AXIS EXTENDS FROM 16N17W TO 8N18W AND THE WAVE
ITSELF IS ASSOCIATED WITH HIGH LOW-LEVEL MOISTURE. SCATTERED
MODERATE CONVECTION IS FROM 12N-16N E OF 19W.

TROPICAL WAVE IS BETWEEN THE ITCZ AND THE MONSOON TROUGH WITH
AXIS EXTENDING FROM 14N29W TO 5N34W MOVING W AT 15 KT. MOST OF
THE WAVE IS IN A VERY MOIST ENVIRONMENT THAT IS FAVORING
SCATTERED SHOWERS FROM 4N-11N BETWEEN 30W-38W.

TROPICAL WAVE IS JUST N OF THE ITCZ WITH AXIS EXTENDING FROM
13N46W TO 6N48W MOVING W AT 15 KT. THE WAVE IS EMBEDDED IN THE
DRY ENVIRONMENT OF THE SAHARAN AIR LAYER WHICH IS HINDERING
CONVECTION AT THE TIME.

TROPICAL WAVE IS WITHIN 360 NM E OF THE LESSER ANTILLES WITH
AXIS EXTENDING FROM 19N52W TO 9N55W MOVING W AT 15 KT. SIMILAR
TO THE PRIOR WAVE...THE WAVE IS EMBEDDED IN THE DRY ENVIRONMENT
OF THE SAHARAN AIR LAYER WHICH IS HINDERING CONVECTION AT THE
TIME.

TROPICAL WAVE IS ON THE WESTERN CARIBBEAN WITH AXIS EXTENDING
FROM 21N82W TO 10N84W MOVING W AT 15 KT. THE WAVE IS EMBEDDED IN
A MODERATE MOIST ENVIRONMENT. THE WAVE IS ENHANCING SCATTERED
SHOWERS AND ISOLATED TSTMS N OF 19N W OF 80W. S OF THAT LATITUDE
STRONG DEEP LAYER ENVIRONMENTAL SHEAR IS INHIBITING CONVECTION.

...ITCZ/MONSOON TROUGH...
THE MONSOON TROUGH EXTENDS ACROSS AFRICA TO NORTHERN
SENEGAL...IT THEN RESUMES W OF A TROPICAL WAVE NEAR 10N19W TO
7N30W. THE ITCZ BEGINS NEAR 7N36W AND CONTINUES ALONG 5N47W TO
7N53W. IN ADDITION TO THE CONVECTION ASSOCIATED WITH THE
WAVES...SCATTERED MODERATE CONVECTION IS FROM 6N-9N BETWEEN 22W-
29W...FROM 5N-9N BETWEEN 49W-54W.

...DISCUSSION...

GULF OF MEXICO...
AN UPPER LEVEL TROUGH EXTENDS FROM MICHIGAN TO A BASE OVER THE
NE GULF COASTLINE. TROUGHINESS ALOFT IS SUPPORTING A STATIONARY
FRONT EXTENDING FROM N FLORIDA NEAR 30N84W SW TO 29N90W TO THE
SE COAST OF TEXAS NEAR 29N94W. A MID-LEVEL TROUGH SUPPORTS A PRE-
FRONTAL TROUGH EXTENDING FROM 30N82W TO 27N87W TO 27N91W. ALOFT
AND SOUTH OF THE NE GULF COASTLINE THERE IS A DIFFLUENT
ENVIRONMENT ACROSS THE EASTERN GULF THAT IS ENHANCING SCATTERED
HEAVY SHOWERS AND TSTMS AHEAD OF THE SURFACE TROUGH TO 24N.
OTHERWISE...A 1014 MB HIGH IS OVER THE WESTERN GULF NEAR 25N93W.
VARIABLE WINDS OF 10 KT ARE BASIN-WIDE. A TROPICAL WAVE
CURRENTLY OVER THE W CARIBBEAN WILL MOVE INTO THE BAY OF
CAMPECHE BY EARLY FRIDAY.

CARIBBEAN SEA...
A MID-LEVEL HIGH IS OVER THE NW CARIBBEAN WHICH ALONG A SHORT-
WAVE TROUGH OVER THE SW N ATLC IS CAUSING A DIFFLUENT
ENVIRONMENT OVER CUBA TO SUPPORT HEAVY SHOWERS AND TSTMS ISLAND-
WIDE. SOUTH OF CUBA A TROPICAL WAVE WITH AXIS ALONG 84W IS
ENHANCING SCATTERED SHOWERS AND ISOLATED TSTMS N OF 19N W OF
80W. SEE TROPICAL WAVES SECTION FOR MORE DETAILS. HIGH PRESSURE
IS OVER THE EASTERN CARIBBEAN WHICH IS SUPPORTING A TIGHTER
PRESSURE GRADIENT OVER THE SOUTHERN-CENTRAL CARIBBEAN. THIS IS
GENERATING A MODERATE TO FRESH BREEZE S OF 16N BETWEEN 64W-78W.
OTHERWISE...STRONG DEEP LAYER ENVIRONMENTAL SHEAR IS HINDERING
THE DEVELOPMENT OF CONVECTION. TROPICAL WAVE OVER THE W BASIN WILL
MOVE OUT OF THE AREA OF DISCUSSION THU MORNING WHILE A NEW WAVE
MOVE ACROSS THE EASTERN CARIBBEAN.

...HISPANIOLA...
AN UPPER-LEVEL LOW OVER THE SW N ATLC EXTENDS A TROUGH SOUTHWARD
ACROSS THE ISLAND TO SUPPORT ISOLATED SHOWERS ISLAND-WIDE.
SHOWERS ARE EXPECTED TO CEASE BY THU MORNING.

ATLANTIC OCEAN...
A MID-LEVEL SHORT-WAVE TROUGH IS OVER THE SW N ATLC AS WELL AS
UPPER-LEVEL DIFFLUENCE. THIS ENVIRONMENT ALONG WITH ABUNDANT
MOISTURE IN THE REGION ARE SUPPORTING HEAVY SHOWERS AND TSTMS N
OF 23N W OF 74W. FARTHER EAST...AN UPPER-LEVEL CYCLONE CENTERED
NEAR 27N71W SUPPORTS AN AREA OF SCATTERED MODERATE CONVECTION
AND TSTMS N OF 20N BETWEEN 63W-71W. OTHERWISE...THE CENTRAL AND
EASTERN ATLC ARE UNDER THE INFLUENCE OF A SURFACE RIDGE ANCHORED
BY A 1031 MB HIGH CENTERED NEAR 34N52W. THERE IS A WEAKNESS IN
THE RIDGE ANALYZED AS A SURFACE TROUGH FROM 30N35W SW TO 27N42W
TO 27N48W BUT WITH NO CONVECTION ASSOCIATED WITH IT.

FOR ADDITIONAL INFORMATION PLEASE VISIT
HTTP://WWW.HURRICANES.GOV/MARINE

$$
NR