[Tropical] Tropical Weather Discussion

[EMWIN Server]

AXNT20 KNHC 070003
TWDAT

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
705 PM EST FRI NOV 06 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 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH
2315 UTC.

...TROPICAL WAVES...

A TROPICAL WAVE IS OVER THE CENTRAL ATLC WITH AXIS EXTENDING
FROM 17N41W TO 07N42W...MOVING W AT 15 TO 20 KT OVER THE PAST 24
HOURS. SSMI TPW INDICATES THE WAVE IS EMBEDDED WITHIN A SURGE OF
HIGH MOISTURE. SUBTLE 700 MB TROUGHING IS INDICATED IN MODEL
FIELDS BETWEEN 38W AND 45W. ISOLATED MODERATE CONVECTION IS FROM
07N TO 14N BETWEEN 40W AND 46W.

A TROPICAL WAVE IS OVER THE E CARIBBEAN WITH AXIS EXTENDING FROM
19N64W TO 10N66W...MOVING W AT 15 TO 20 KT OVER THE PAST 24
HOURS. SSMI TPW INDICATES THE WAVE IS EMBEDDED WITHIN THE
LEADING EDGE SURGE OF HIGH MOISTURE. A SHARP INVERTED TROUGH IS
EVIDENT AT 700 MB BETWEEN 59W AND 67W WITH A 850 MB MAXIMUM IN
VORTICITY NEAR 14N64W. SCATTERED MODERATE CONVECTION IS FROM 13N
TO 19N BETWEEN 59W AND 66W.

A TROPICAL WAVE IS OVER THE SW GULF OF MEXICO...S MEXICO...AND
THE E PACIFIC WITH AXIS EXTENDING FROM 25N93W TO A 1012 MB
SURFACE LOW NEAR 20N93W TO 13N94W...MOVING W AT AROUND 15 KT
OVER THE PAST 24 HOURS. SSMI TPW INDICATES THE WAVE IS EMBEDDED
WITHIN A VERY MOIST ENVIRONMENT. 700 MB TROUGHING IS INDICATED
BETWEEN 90W AND 97W. SCATTERED MODERATE CONVECTION IS FROM 22N
TO 27N BETWEEN 91W AND 97W.

...ITCZ/MONSOON TROUGH...

THE MONSOON TROUGH EXTENDS ACROSS AFRICA INTO THE E TROPICAL
ATLC NEAR 11N15W TO 10N21W...WHERE THE ITCZ BEGINS AND CONTINUES
TO 09N40W. THE ITCZ THEN RESUMES W OF A TROPICAL WAVE NEAR
08N43W TO 05N54W. SCATTERED MODERATE CONVECTION IS WITHIN 140 NM
OF EITHER SIDE OF THE ITCZ AXIS BETWEEN 24W AND 40W. SCATTERED
MODERATE AND ISOLATED STRONG CONVECTION ARE WITHIN 70 NM OF THE
ITCZ AXIS BETWEEN 43W AND 49W.

...DISCUSSION...

GULF OF MEXICO...

A TROPICAL WAVE IS OVER THE SW GULF OF MEXICO. PLEASE REFER TO
THE TROPICAL WAVES SECTION FOR MORE DETAILS. AN UPPER LEVEL
RIDGE AXIS EXTENDS FROM THE NW CARIBBEAN TO THE EASTERN GULF
WITH A BROAD AREA OF UPPER LEVEL DIFFLUENCE OVER THE CENTRAL
GULF. THIS DIFFLUENCE IS INTERACTING WITH A MOIST AIRMASS TO
SUPPORT SCATTERED SHOWERS AND THUNDERSTORMS S OF 26N BETWEEN 86W
AND 91W. A COLD FRONT IS NEAR THE TX GULF COAST SUPPORTING
ISOLATED THUNDERSTORMS WITHIN 50 NM OF THE FRONTAL BOUNDARY. A
SURFACE RIDGE AXIS EXTENDS FROM THE W ATLC TO N FL TO THE NW
GULF SUPPORTING MAINLY MODERATE EASTERLY SURFACE WINDS ACROSS
THE ENTIRE GULF BASIN. LOCALLY FRESH EASTERLY WINDS ARE OVER THE
SOUTHERN GULF NEAR CONVECTION AND THE TROPICAL WAVE. THE SURFACE
LOW IS FORECAST TO BREAK AWAY FROM THE TROPICAL WAVE AND MOVE NW
TO THE NW GULF TONIGHT AND SATURDAY AND INTERACT WITH AN UPPER
TROUGH OVER THE S CENTRAL US. THIS WILL SUPPORT ONGOING
CONVECTION OVER THE NW GULF THROUGH SATURDAY. MODELS ARE
INDICATING THIS AREA OF CONVECTION TO THEN MEANDER SLOWLY EAST
ACROSS THE NORTHERN GULF SATURDAY NIGHT AND SUNDAY.

CARIBBEAN SEA...

A BROAD UPPER RIDGE IS CENTERED OVER THE WESTERN CARIBBEAN AND
CENTRAL AMERICA. SSMI TPW SHOWS A VERY MOIST AIRMASS W OF 83W
WHICH IS INTERACTING WITH THE UPPER LEVEL DIFFLUENCE OF THE
RIDGE TO SUPPORT ISOLATED MODERATE CONVECTION W OF A LINE FROM
21N85W TO 11N86W. AN ELONGATED UPPER LEVEL TROUGH EXTENDS FROM
THE BAHAMAS TO HISPANIOLA TO THE SE CARIBBEAN. THE TROUGH
SUPPORTS THUNDERSTORMS MAINLY OVER AND NEAR THE LAND AREA OF THE
GREATER ANTILLES. THE SE PORTION OF THE TROUGH IS INTERACTING
WITH A TROPICAL WAVE TO SUPPORT CONVECTION OVER THE EASTERN
CARIBBEAN. PLEASE REFER TO THE TROPICAL WAVES SECTION FOR MORE
DETAILS. MAINLY MODERATE TO FRESH TRADE WINDS COVER THE
CARIBBEAN BASIN. OVER THE NEXT 24 HOURS CONVECTION ASSOCIATED
WITH THE TROPICAL WAVE OVER THE EASTERN CARIBBEAN IS FORECAST TO
MOVE NW TOWARD PUERTO RICO AND HISPANIOLA...EXTEND S OF THESE
LAND AREAS TO NEAR 15N.

...HISPANIOLA...

SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS COVER HISPANIOLA
THIS EVENING AS A MODERATELY MOIST AIRMASS INTERACTS WITH AN
UPPER TROUGH ACROSS THE REGION. A TROPICAL WAVE IS APPROACHING
HISPANIOLA FROM THE EAST. THIS WAVE WILL BRING AN INCREASE IN
SHOWER AND THUNDERSTORM ACTIVITY TO THE AREA BEGINNING SATURDAY
AFTERNOON AND PERSISTING THROUGH SUNDAY. DURING THAT TIME
PERIOD...LOCALLY HEAVY RAINFALL MAY BE POSSIBLE.

ATLANTIC OCEAN...

AN UPPER TROUGH EXTENDS FROM THE BAHAMAS TO HISPANIOLA TO THE
EASTERN CARIBBEAN. THIS TROUGH SUPPORTS SCATTERED SHOWERS AND
ISOLATED THUNDERSTORMS ACROSS THE MUCH OF THE BAHAMAS AND
OFFSHORE WATERS WITHIN 50 NM OF THE ISLANDS...INCLUDING THE
TURKS AND CAICOS. A LARGE UPPER TROUGH OVER THE N ATLC CONTINUES
TO SUPPORT A COLD FRONT THAT ENTERS THE AREA OF DISCUSSION NEAR
31N26W TO 25N38W TO 23N60W TO 27N70W. SHOWERS ARE WITHIN 100 NM
OF THE FRONT E OF 55W. SHOWERS AND ISOLATED THUNDERSTORMS ARE
WITHIN 100 NM S OF THE FRONT W OF 55W. A SURFACE TROUGH IS OVER
THE TROPICAL CENTRAL ATLC WITH AN AXIS THAT EXTENDS FROM 19N56W
TO 10N58W. SCATTERED MODERATE CONVECTION IS FROM 11N TO 20N
BETWEEN 51W AND 57W. OVER THE NEXT 24 HOURS CONVECTION WILL
CONTINUE NEAR THE SURFACE TROUGH OVER THE CENTRAL ATLC AS IT
MOVES NW. THE WESTERN PORTION OF THE COLD FRONT WILL DISSIPATE
WHILE THE EASTERN PORTION CONTINUES TO MOVE SE ACROSS THE
EASTERN ATLC.

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

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