[Tropical] Tropical Weather Discussion

[EMWIN Server]

AXNT20 KNHC 180552
TWDAT

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
205 AM EDT THU JUN 18 2015

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 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH
0515 UTC.

...SPECIAL FEATURES...
A STRONG PRESSURE GRADIENT EXISTS BETWEEN A 1019 MB HIGH
CENTERED EAST OF THE BAHAMAS NEAR 26N70W AND LOWER PRESSURE
FOCUSED ON A 1005 MB LOW CENTERED ACROSS NORTHERN COLOMBIA NEAR
10N75W THAT IS RESULTING IN NEAR GALE FORCE E-NE WINDS THIS
EVENING WITHIN CLOSE PROXIMITY TO THE COAST OF COLOMBIA. THIS
WIND FIELD IS FORECAST TO INCREASE TO GALE FORCE OVERNIGHT AS
THE PRESSURE GRADIENT STRENGTHENS SLIGHTLY. SEE LATEST NWS HIGH
SEAS FORECAST UNDER AWIPS/WMO HEADERS MIAHSFAT2/FZNT02 KNHC FOR
MORE DETAILS.

...TROPICAL WAVES...
TROPICAL WAVE EXTENDS FROM 07N26W TO 15N25W MOVING W AT 15 KT.
THE WAVE COINCIDES WITH HIGHER MOISTURE VALUES ON TOTAL
PRECIPITABLE WATER IMAGERY BETWEEN 18W-31W. NO SIGNIFICANT DEEP
CONVECTION IS ASSOCIATED WITH THE WAVE AT THIS TIME.

TROPICAL WAVE EXTENDS FROM 06N64W TO 15N63W MOVING W AT 15-20
KT. THE WAVE COINCIDES WITH WEAK 700 MB TROUGHING BETWEEN 60W-
68W EMBEDDED WITHIN A LENGTHY EASTERLY JET STRETCHING FROM
12N36W TO 15N76W. NO SIGNIFICANT DEEP CONVECTION IS ASSOCIATED
WITH THE WAVE AT THIS TIME.

TROPICAL WAVE EXTENDS FROM 09N78N TO 18N78W MOVING W AT 15-20
KT. THE TOTAL PRECIPITABLE WATER IMAGERY SHOWS THE WAVE EMBEDDED
WITHIN INCREASED VALUES OF DEEP MOISTURE ACROSS THE WESTERN
CARIBBEAN SEA. NO SIGNIFICANT CONVECTION IS NOTED WITH THE WAVE
AT THIS TIME.

...ITCZ/MONSOON TROUGH...
THE MONSOON TROUGH EXTENDS FROM THE AFRICAN COAST NEAR 12N16W TO
10N23W. THE INTERTROPICAL CONVERGENCE ZONE AXIS EXTENDS FROM
08N30W TO 03N51W. SCATTERED MODERATE CONVECTION IS FROM 07N-10N
BETWEEN 12W-15W. ISOLATED MODERATE CONVECTION IS FROM 05N-09N
BETWEEN 27W-37W.

...DISCUSSION...

GULF OF MEXICO...
AN UPPER LEVEL LOW IS CENTERED OVER THE NORTHERN YUCATAN
PENINSULA NEAR 21N87W THAT IS PROVIDING MUCH OF THE GULF WITH
EAST-NORTHEASTERLY FLOW ALOFT WHICH ON WATER VAPOR IMAGERY
REMAINS RELATIVELY DRY AND STABLE ALOFT. AT THE SURFACE...
STABILITY PREVAILS AS WELL DUE TO SURFACE RIDGING ANCHORED BY A
1018 MB HIGH CENTERED IN THE NE GULF NEAR 28N85W. ONLY IN THE
FAR NW PORTION OF THE BASIN ARE A FEW SCATTERED SHOWERS AND
ISOLATED TSTMS OCCURRING N OF 26N W OF 95W. THIS ACTIVITY LIES
WITHIN AN AREA OF MODERATE TO FRESH SOUTHERLY FLOW ACROSS THE
WESTERN GULF...WHILE CLOSER TO THE HIGH CENTER GENTLE TO
OCCASIONAL MODERATE SE WINDS PREVAIL. THE SURFACE RIDGE AXIS IS
FORECAST TO REMAIN ALONG 28N FROM THE FLORIDA PENINSULA TO THE
SE TEXAS COAST THROUGH FRIDAY AND SHIFT SLIGHTLY NORTH INTO
SATURDAY.

CARIBBEAN SEA...
WITH AN UPPER LEVEL LOW CENTERED OVER THE NORTHERN YUCATAN
PENINSULA NEAR 21N87W...MUCH OF THE CARIBBEAN IS UNDER THE
INFLUENCE OF WEST-SOUTHWESTERLY FLOW STEMMING FROM THE LOW.
MIDDLE TO UPPER LEVEL MOISTURE REMAINS ENHANCED NEAREST TO THE
UPPER LEVEL FEATURE WITH POSSIBLE ISOLATED SHOWERS OCCURRING W
OF 78W THIS EVENING. LATE EVENING SHOWERS AND TSTM ACTIVITY
CONTINUES TO DIMINISH ACROSS PORTIONS OF CUBA WITH A FEW
ISOLATED SHOWERS AND TSTMS REMAINING ACROSS HISPANIOLA.
OTHERWISE...A PAIR OF TROPICAL WAVES ARE MOVING ACROSS THE
CENTRAL AND EASTERN CARIBBEAN...EACH INFLUENCED BY A DRY SAHARAN
AIR LAYER ALOFT PROVIDING FOR OVERALL STABLE CONDITIONS FOR THE
OVERNIGHT PERIOD. THE PRIMARY IMPACT WILL REMAIN THE STRONG TO
NEAR GALE TRADES GENERALLY S OF 18N BETWEEN 65W-83W. GIVEN THE
INCREASED PRESSURE GRADIENT ACROSS THE REGION...THESE TRADES ARE
EXPECTED TO PERSIST THROUGH THE UPCOMING WEEKEND INTO EARLY NEXT
WEEK.

...HISPANIOLA...
CURRENTLY...A FEW LINGERING ISOLATED SHOWERS AND TSTMS REMAIN
ACROSS THE ISLAND AND THIS ACTIVITY IS EXPECTED TO CONTINUE
DIMINISHING THROUGH THE OVERNIGHT HOURS. OTHERWISE...WESTERLY
FLOW ALOFT PREVAILS AND THIS WILL LIKELY PROVIDE AMPLE MIDDLE TO
UPPER LEVEL DYNAMICS FOR LATE AFTERNOON AND EARLY EVENING
SCATTERED SHOWERS AND TSTMS DUE TO DIFFLUENCE ALOFT AND PEAK
DAYTIME HEATING AND INSTABILITY IN THE LOWER LEVELS.

ATLANTIC OCEAN...
A 1019 MB HIGH IS CENTERED EAST OF THE BAHAMAS NEAR 26N70W. FAIR
SKIES ARE NOTED ACROSS MUCH OF THE SW NORTH ATLC THIS EVENING.
TO THE EAST OF THIS HIGH CENTER...AN UPPER LEVEL LOW IS NOTED ON
WATER VAPOR IMAGERY CENTERED NEAR 26N59W. MID-LEVEL MOISTURE AND
CLOUDINESS INCREASES IN THE VICINITY OF THE FEATURE BETWEEN 56W-
67W WITH ISOLATED SHOWERS POSSIBLE. THE REMAINDER OF THE CENTRAL
AND EASTERN ATLC FALL UNDER THE INFLUENCE OF SURFACE HIGH
PRESSURE AND RIDGING WITH OVERALL FAIR CONDITIONS PREVAILING.

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

$$
HUFFMAN
This weather bulletin was brought to you by:
www.nashvilleweather.net