[Tropical] Tropical Weather Discussion

[EMWIN Server]

AXNT20 KNHC 091805
TWDAT

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
205 PM EDT SAT AUG 09 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 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH
1745 UTC.

...TROPICAL WAVES...

TROPICAL WAVE IS WITHIN 650 NM EAST OF THE LESSER ANTILLES WITH
AXIS EXTENDING FROM 21N48W TO 9N50W MOVING W AT 20 KT. METEOSAT
PSEUDO NATURAL AND SAL TRACKING IMAGERY SHOW THE PRESENCE OF
DUST AND DRY AIR IN THE WAVE ENVIRONMENT WHICH CONTINUE TO
INHIBIT CONVECTION N OF 12N. SCATTERED SHOWERS ARE IN THE
SOUTHERN WAVE ENVIRONMENT JUST WEST OF THE ITCZ FROM 9N-
11N...COINCIDING WITH DEEP LAYER MOISTURE AND A ZONE OF MIDDLE
TO UPPER LEVEL DIFFLUENCE.

TROPICAL WAVE IS ACROSS THE CENTRAL CARIBBEAN WITH AXIS
EXTENDING FROM 19N70W TO 11N70W MOVING W AT 15 KT. THE WAVE IS
ASSOCIATED WITH DEEP LAYER MOISTURE N OF 15N WHICH ALONG UPPER
LEVEL DIVERGENCE PROVIDED BY AN ELONGATED ANTICYCLONE SUPPORT
SCATTERED MODERATE CONVECTION AND TSTMS FROM 15N-20N BETWEEN 69W-
73W...INCLUDING THE DOMINICAN REPUBLIC AND HAITI.

TROPICAL WAVE IS MOVING ACROSS THE YUCATAN PENINSULA...GUATEMALA
AND E PACIFIC WATERS. THE WAVE AXIS EXTENDS FROM 20N88W TO
10N90W AND IS MOVING W AT 15 KT. A BROAD MID-UPPER LEVEL
INVERTED TROUGH SUPPORT THIS WAVE AS WELL AS SCATTERED MODERATE
CONVECTION AND ISOLATED TSTMS OVER THE NW CARIBBEAN W OF
80W...INCLUDING THE EASTERN YUCATAN PENINSULA AND BELIZE.

...ITCZ/MONSOON TROUGH...

THE MONSOON TROUGH EXTENDS FROM THE WEST COAST OF AFRICA NEAR
15N16W TO 11N29W TO 10N40W. THE ITCZ BEGINS NEAR 10N40W AND
CONTINUES TO 10N48W. SCATTERED MODERATE CONVECTION AND ISOLATED
TSTMS ARE FROM 5N-14N E OF 21W.

...DISCUSSION...

THE GULF OF MEXICO...

AN ELONGATED MIDDLE-LEVEL ANTICYCLONE EXTENDING FROM THE CENTRAL
PLAINS SE INTO THE CENTRAL AND WESTERN GULF SUPPORT SURFACE
RIDGING ACROSS THE BASIN WHICH IS BEING ANCHORED BY A 1018 MB
HIGH NEAR 27N90W. ANTICYCLONIC WIND OF 5-10 KT ASSOCIATED WITH
THIS HIGH IS ADVECTING LOW LEVEL MODERATE MOISTURE INTO THE
BASIN FROM THE CARIBBEAN AS WELL AS THE SW N ATLC WHICH IS
FUELING ISOLATED MODERATE CONVECTION AND TSTMS N OF 22N E OF
93W. A MID-UPPER LEVEL LOW CENTERED INLAND NE MEXICO CONTINUE TO
SUPPORT SCATTERED MODERATE CONVECTION AND ISOLATED TSTMS OVER
THE FAR NW BASIN N OF 22N W OF 94W. A TROPICAL WAVE IS MOVING
ACROSS THE YUCATAN PENINSULA INTO THE E PAC WATERS AND SUPPORTS
ISOLATED SHOWERS ACROSS THE YUCATAN CHANNEL. SEE THE TROPICAL WAVES
SECTION ABOVE. OTHERWISE...SURFACE RIDGING WILL PREVAIL ACROSS
GREAT PORTIONS OF THE GULF DURING THE NEXT THREE DAYS. THE
NORTHERN PORTION OF THE TROPICAL WAVE IS FORECAST TO ENTER THE
BAY OF CAMPECHE SUN MORNING WHICH WILL BRING RAINSHOWERS TO THE
S-SW GULF THROUGH SUN NIGHT. ANOTHER WAVE IS EXPECTED TO ENTER
THE SOUTHERN GULF ON WED MORNING.

THE CARIBBEAN SEA...

A TROPICAL WAVE WITH AXIS CURRENTLY MOVING ACROSS THE YUCATAN
PENINSULA AND NORTHERN CENTRAL AMERICA CONTINUE TO SUPPORT
SCATTERED MODERATE CONVECTION AND ISOLATED TSTMS OVER THE NW
CARIBBEAN FROM 18N-22N W OF 81W. SCATTERED HEAVY SHOWERS AND
TSTMS ARE OVER THE SW CARIBBEAN S OF 14N W OF 79W BEING ENHANCED
BY THE MONSOON TROUGH AND BANKING OF LOW LEVEL MOISTURE FROM THE
COAST OF NORTHERN NICARAGUA TO CENTRAL PANAMA. A SECOND TROPICAL
WAVE IS MOVING ACROSS THE CENTRAL BASIN. THE WAVE IS SUPPORTING
SCATTERED HEAVY SHOWERS AND TSTMS N OF 16N BETWEEN 69W-74W
...INCLUDING HISPANIOLA. THE WAVE ALSO CONTINUE TO SUPPORT
SHOWERS AND TSTMS ACROSS WESTERN PUERTO RICO. SEE THE TROPICAL
WAVES SECTION FOR MORE DETAILS. A ZONE OF UPPER LEVEL DIFFLUENCE
IN THE SE CARIBBEAN COINCIDING WITH A PATCH OF DEEP LAYER
MOISTURE SUPPORT SCATTERED MODERATE CONVECTION FROM 11N-14N
BETWEEN 63W-68W. OTHERWISE...THE REMAINDER BASIN IS UNDER FAIR
WEATHER CONDITIONS BEING SUPPORTED BY AN OVERALL DEEP LAYER DRY
ENVIRONMENT. THE PASSAGE OF THE TROPICAL WAVE SUPPORTS TRADES OF 20
KT ACROSS THE CENTRAL AND EASTERN CARIBBEAN WHILE LIGHTER WINDS
OF 15 KT DOMINATE THE NW AND SW BASIN. ISOLATED HEAVY SHOWERS
AND TSTMS ASSOCIATED WITH THE TROPICAL WAVE WILL CONTINUE TO
AFFECT HISPANIOLA AND ADJACENT WATERS OVER THE REMAINDER
WEEKEND.

...HISPANIOLA...

ISOLATED HEAVY RAINSHOWERS AND TSTMS ARE ACROSS SOUTHERN
HISPANIOLA AND ADJACENT WATERS ASSOCIATED WITH A TROPICAL WAVE
MOVING ACROSS THE ISLAND AND THE CENTRAL CARIBBEAN. ISOLATED
SHOWERS ARE ACROSS THE REMAINDER ISLAND. SEE THE TROPICAL WAVES
SECTION FOR MORE DETAILS. SHOWER ACTIVITY ASSOCIATED WITH THE
WAVE IS EXPECTED TO CEASE BY EARLY SUNDAY MORNING.

THE ATLANTIC OCEAN...

A MIDDLE-UPPER LEVEL BROAD TROUGH OVER THE WESTERN ATLC
CONTINUES TO SUPPORT A SURFACE TROUGH EXTENDING FROM 30N58W TO
28N70W TO THE NORTHERN BAHAMAS NEAR 25N78W. ISOLATED SHOWERS AND
TSTMS ARE WITHIN 70 NM EITHER SIDE OF THE TROUGH AXIS. SCATTERED
MODERATE CONVECTION AND TSTMS ARE N OF 28N BETWEEN 77W-80W BEING
ENHANCED BY A ZONE OF MIDDLE LEVEL DIVERGENCE. OTHERWISE...A
SURFACE RIDGE ANCHORED BY A 1028 MB HIGH NEAR 33N38W DOMINATES
ELSEWHERE N OF 22N. FOR TROPICAL WAVES...SEE SECTION ABOVE.

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

$$
NR

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