Tropical Weather Discussion
Issued by NWS

Current Version | Previous Version | Text Only | Print | Product List | Glossary Off
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50

000
AXNT20 KNHC 261035
TWDAT

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
805 AM EDT FRI JUN 26 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH
1015 UTC.

...SPECIAL FEATURES...

...GALE IN THE CARIBBEAN...
A GALE WARNING IS IN EFFECT FOR THE SW CARIBBEAN FROM 11.5N-16N
BETWEEN 70W-81W THROUGH THIS EVENING THEN REDUCING TO AN AREA
ALONG THE COAST OF COLOMBIA THROUGH SUN AFTERNOON. THESE WINDS
ARE GENERATED BY A TIGHT PRESSURE GRADIENT BETWEEN THE SURFACE
RIDGE OVER THE W ATLC AND THE LOWER PRESSURE OVER SOUTH AMERICA.
SEE LATEST NWS HIGH SEAS FORECAST UNDER AWIPS/WMO HEADERS
MIAHSFAT2/FZNT02 KNHC FOR MORE DETAILS.

...TROPICAL WAVES...

TROPICAL WAVE WAS INTRODUCED IN THE E TROPICAL ATLC ALONG 22W-
23W FROM 6N-13NMOVING W NEAR 15 KT. THE TOTAL PRECIPITABLE WATER
IMAGERY SHOWS THE WAVE ALONG THE LEADING EDGE OF A LOW AMPLITUDE
SURGE OF MODERATE MOISTURE. NO ASSOCIATED DEEP CONVECTION.

TROPICAL WAVE IN THE CENTRAL TROPICAL ATLC EXTENDS ALONG 42W-43W
FROM 6N-13N MOVING W 20-25 KT OVER THE PAST 24 HOURS. THE TOTAL
PRECIPITABLE WATER IMAGERY SHOWS THE WAVE ALONG THE LEADING EDGE
OF A LOW AMPLITUDE SURGE OF DEEP MOISTURE. CONVECTION ASSOCIATED
WITH THE ITCZ IS BEING ENHANCED BY THIS WAVE.

TROPICAL WAVE IN W TROPICAL ATLC EXTENDS ALONG 57W/58W FROM 8N-
19N MOVING W 15-20 KT OVER THE PAST 24 HOURS. THE TOTAL
PRECIPITABLE WATER IMAGERY SHOWS THE WAVE IS ALONG THE LEADING
EDGE A HIGH AMPLITUDE SURGE OF MODERATE/DEEP MOISTURE. NO
ASSOCIATED DEEP CONVECTION.

TROPICAL WAVE IN THE W CARIBBEAN EXTENDS ALONG 82W-83W S OF 16N
TO ACROSS PANAMA MOVING W NEAR 15 KT OVER THE PAST 24 HOURS. THE
TOTAL PRECIPITABLE WATER IMAGERY SHOWS THE WAVE IS EMBEDDED
WITHIN SURGE OF DEEP MOISTURE THAT COVERS THE CARIBBEAN W OF
80W. SCATTERED SHOWERS/THUNDERSTORMS ARE WITHIN 45 NM ALONG THE
COAST OF PANAMA W OF THE WAVE TO 81W.

...ITCZ/MONSOON TROUGH...

THE MONSOON TROUGH EXTENDS ACROSS AFRICA INTO THE TROPICAL ATLC
NEAR 12N16W TO E OF THE NEWLY INTRODUCED TROPICAL WAVE NEAR
9N21W. THE ITCZ BEGINS W OF THE WAVE NEAR 9N25W AND CONTINUES TO
E OF THE NEXT WAVE NEAR 8N41W THEN RESUMES W OF THE WAVE NEAR
7N44W ALONG 5N47W TO SOUTH AMERICA NEAR 6N54W. SCATTERED
MODERATE/ISOLATED STRONG CONVECTION IS WITHIN 90 NM N OF THE
ITCZ BETWEEN 38W-47W AND WITHIN 180 NM S OF THE ITCZ BETWEEN 39W-
43W.

...DISCUSSION...

GULF OF MEXICO...
AN UPPER RIDGE IS ANCHORED OVER THE NE GULF NEAR 29N84W COVERING
THE N GULF OF MEXICO TO CENTRAL LOUISIANA AND THE N FLORIDA
PENINSULA TO 85W. THE REMAINDER OF THE GULF IS UNDER A LARGE
UPPER LOW THAT IS CENTERED OVER THE W GULF NEAR 25N95W.
DIFFLUENT FLOW OVER THE N GULF IS GENERATING SCATTERED SHOWERS/
ISOLATED THUNDERSTORMS N OF 29N BETWEEN THE BIG BEND AREA OF
FLORIDA TO THE LOUISIANA/TEXAS BORDER. THE UPPER LOW IS
GENERATING CLUSTERS OF SCATTERED SHOWERS AND POSSIBLE ISOLATED
THUNDERSTORMS OVER THE SW GULF S OF 24N BETWEEN 88W-93W AND 20N-
22N W OF 95W TO INLAND OVER MEXICO. THIS IS LEAVING THE
REMAINDER OF THE GULF WITH MOSTLY CLEAR SKIES THIS MORNING. A
WEAK SURFACE RIDGE EXTENDS FROM THE W ATLC ACROSS FLORIDA
COVERING THE GULF WITH A WEAK 1019 MB HIGH NEAR 27N87W. SURFACE
RIDGE AXIS OVER THE N GULF WILL DRIFT S TO THE CENTRAL GULF
THROUGH THE WEEKEND. THE SURFACE TROUGH WILL MOVE W-NW ACROSS
THE SW GULF SAT THROUGH SUN.

CARIBBEAN SEA...
A WEAK UPPER RIDGE EXTENDS FROM NEAR 17N84W THROUGH THE YUCATAN
CHANNEL WHILE THE REMAINDER OF THE CARIBBEAN IS UNDER NEAR ZONAL
WESTERLY FLOW ALOFT. LINGERING MOISTURE COUPLED WITH THE
DIFFLUENT FLOW OVER THE NW CARIBBEAN ARE GENERATING SCATTERED
SHOWERS/ISOLATED THUNDERSTORMS S OF 21N W OF 84W TO INLAND OVER
GUATEMALA AND THE YUCATAN PENINSULA. THIS IS LEAVING THE
REMAINDER OF THE CARIBBEAN WITH CLEAR SKIES THIS MORNING. A
PERSISTENT W ATLC SURFACE RIDGE WILL MAINTAIN STRONG TO GALE
FORCE TRADE WINDS ACROSS THE S/CENTRAL CARIBBEAN THROUGH THE
WEEKEND. THE W CARIBBEAN TROPICAL WAVE WILL MOVE OVER CENTRAL
AMERICA TODAY. THE NEXT TROPICAL WAVE IS APPROACHING THE LESSER
ANTILLES AND WILL MOVE INTO THE E CARIBBEAN LATER THIS MORNING
CROSSING THE CENTRAL CARIBBEAN TONIGHT AND SAT THEN MOVE INTO
THE W CARIBBEAN SAT NIGHT AND SUN. A THIRD TROPICAL WAVE WILL
MOVE INTO THE E CARIBBEAN SAT EVENING THEN INTO THE CENTRAL
CARIBBEAN SUN NIGHT.

...HISPANIOLA...
SKIES REMAIN CLEAR ACROSS THE ISLAND THIS MORNING. AFTERNOON/
EVENING SHOWERS/THUNDERSTORMS ARE POSSIBLE FOR TODAY DUE TO
DAYTIME HEATING AND OROGRAPHIC LIFTING. THE FIRST OF NEXT
TROPICAL WAVES WILL APPROACH THE ISLAND FRI NIGHT/EARLY SAT WITH
A SECOND ON SUN EVENING. THIS WILL INCREASE THE MOISTURE AND
THUS INCREASE THE CHANCES OF MORE WIDESPREAD SHOWERS/
THUNDERSTORMS THROUGH THE REMAINDER OF THE WEEKEND.

ATLANTIC OCEAN...
BROAD BUT WEAK UPPER TROUGH COVERS THE W ATLC WITH A PAIR OF
UPPER LOWS...ONE OVER THE CENTRAL BAHAMAS NEAR 25N76W AND A
WEAKER ONE NEAR 27N68W. SCATTERED SHOWERS/ISOLATED THUNDERSTORMS
ARE FROM 23N-28N BETWEEN 72W-79W INCLUDING THE N BAHAMA ISLANDS
AND ARE ASSOCIATED WITH THE UPPER LOW. A BROAD E/W SURFACE RIDGE
DOMINATES THE ATLC BASIN WITH A 1029 MB HIGH NEAR 28N50W. THIS
SURFACE RIDGE EXTENDS W ACROSS FLORIDA INTO THE GULF OF MEXICO.
NOAA/NESDIS AEROSOL PRODUCT AND THE FIRST VISIBLE SATELLITE
IMAGERY INDICATES THAT A LARGE DENSE PLUMB OF AEROSOLS OR
SAHARAN DUST COVERS THE TROPICS S OF 27N E OF 58W. THE SURFACE
RIDGE WILL BEGIN SHIFT SLIGHTLY S THIS AFTERNOON THROUGH THE
WEEKEND.

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

$$
PAW



USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.