[Tropical] Tropical Weather Discussion

[EMWIN Server]

AXNT20 KNHC 080006
TWDAT

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
805 PM EDT SUN JUL 07 2013

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.

...SPECIAL FEATURES...
A 1008 MB LOW IS EMBEDDED WITHIN THE ITCZ AXIS NEAR 09N43W.
UPPER LEVEL DIFFLUENCE FROM AN INVERTED TROUGH WITH AXIS NEAR
50W AND A RIDGE EXTENDING TO 48W IS SUPPORTING A CLUSTER OF
MODERATE CONVECTION FROM 05N-11N BETWEEN 44W-47W. THE FORMER
TROPICAL WAVE THAT WAS ASSOCIATED WITH THIS LOW IS CURRENTLY
ANALYZED AS A SURFACE TROUGH NEAR 340 NM EAST OF THE LESSER
ANTILLES. SEE THE ATLC SECTION BELOW FOR MORE INFORMATION ABOUT
IT. OTHERWISE...THE LOW IS EXPECTED TO MOVE W-NW WITH A HIGH
CHANCE OF BECOMING A TROPICAL CYCLONE WITHIN THE NEXT 48 HOURS.

...TROPICAL WAVES...
A TROPICAL WAVE CAME OFF THE WEST AFRICAN COAST THIS EARLY THIS
AFTERNOON. ITS AXIS CURRENTLY EXTENDS FROM 12N21W TO 05N23W AND
IS EMBEDDED WITHIN A MODERATE TO HIGH MOIST ENVIRONMENT WITHIN
THE MONSOON TROUGH AXIS. A SAL OUTBREAK SPREADS OVER THE EASTERN
ATLC AND ENGULFS THIS WAVE...HOWEVER THE DRY AIR IS DISTANT FROM
ITS ENVIRONMENT. SMALL CLUSTERS OF MODERATE CONVECTION SURROUNDS
THE WAVE AXIS FROM 04N-12N BETWEEN 20W-27W.

A TROPICAL WAVE CONTINUES TO MOVE ACROSS LA HISPANIOLA THIS
EVENING WITH AXIS FROM 24N68W TO 15N73W. THE WAVE IS EMBEDDED
WITHIN A MODERATE MOIST ENVIRONMENT AT THE LOWER LEVELS AS
DEPICTED BY TOTAL PRECIPITABLE WATER IMAGERY...SPECIALLY OUTSIDE
THE ISLAND. UPPER LEVEL DIFFLUENCE FROM A CYCLONIC CIRCULATION
OVER THE W ATLC NEAR 24N72W AND AN ANTICYCLONIC CIRCULATION OVER
THE EASTERN CARIBBEAN NEAR 13N65W IS ENHANCING SCATTERED SHOWERS
AND THUNDERSTORMS OVER HAITI...THE NORTHERN DOMINICAN REPUBLIC
AS WELL AS FROM 20N-24N BETWEEN 65W-70W.

...ITCZ/MONSOON TROUGH...
THE MONSOON TROUGH AXIS EXTENDS FROM THE WEST AFRICAN COAST NEAR
09N13W TO 07N23W 09N33W. THE INTERTROPICAL CONVERGENCE ZONE AXIS
EXTENDS FROM 09N33W TO 10N42W...IT RESUMES SW OF A 1008 MB LOW
ALONG 08N45W TO 03N51W. BESIDES THE CONVECTION ALREADY DISCUSSED
ASSOCIATED WITH THE LOW AND THE TROPICAL WAVE...A BIG CLUSTER OF
MODERATE TO ISOLATED STRONG CONVECTION WITH EMBEDDED
THUNDERSTORMS IS FROM 07N-15N E OF 19W.

...DISCUSSION...

GULF OF MEXICO...
RETURN FLOW SPREADS ACROSS THE ENTIRE GULF THIS EVENING WITH
WINDS RANGING FROM 10-15 KT E OF 90W AND 15-20 KT W OF THAT
LONGITUDE. THIS ANTICYCLONIC FLOW HAS BEEN BANKING HIGH LOWER
LEVELS MOISTURE TO THE NW GULF WHICH COMBINED WITH AN UPPER
LEVEL DIFFLUENT PATTERN CONTINUES TO ENHANCE RAINSHOWERS AND
ISOLATED THUNDERSTORMS. SCATTERED MODERATE CONVECTION IS
OBSERVED W OF A LINE FROM 30N88W TO 24N92W 18N95W...INCLUDING
SOUTHERN MISSISSIPPI AND SE LOUISIANA. DIFFLUENT FLOW IN THE
MIDDLE LEVELS IS ENHANCING SCATTERED SHOWERS AND THUNDERSTORMS
OVER THE CENTRAL GULF FROM 23N-27N BETWEEN 86W-88W AS WELL AS
WITHIN 50 NM OFF THE WESTERN COAST OF FLORIDA FROM 25N-29N. A
SURFACE TROUGH EXTENDS OVER THE WESTERN YUCATAN PENINSULA FROM
21N89W TO 18N91W IN THE BAY OF CAMPECHE TO INLAND SOUTHERN
MEXICO. A CLUSTER OF MODERATE CONVECTION IS ASSOCIATED WITH THIS
TROUGH WHICH EXTENDS 30 NM OFF THE YUCATAN COAST FROM 19N-21W.

SURFACE RIDGING WILL CONTINUE ACROSS MUCH OF THE GULF WITHIN THE
NEXT 48 HOURS WITH SOME TROUGHINESS LINGERING OVER THE BAY OF
CAMPECHE. RAINSHOWERS ACTIVITY IS EXPECTED TO CONTINUE ACROSS
THE NW GULF DURING MONDAY AND WILL SLIGHTLY DECREASE DURING
TUESDAY.

CARIBBEAN SEA...
A TROPICAL WAVE MOVES ACROSS LA HISPANIOLA THIS EVENING. THIS
WAVE IS EMBEDDED WITHIN A MODERATE MOIST ENVIRONMENT AT THE
LOWER LEVELS AND UPPER LEVEL DIFFLUENCE FROM A CYCLONIC
CIRCULATION OVER THE W ATLC NEAR 24N72W AND AN ANTICYCLONIC
CIRCULATION OVER THE EASTERN CARIBBEAN NEAR 13N65W IS ENHANCING
SCATTERED SHOWERS AND THUNDERSTORMS OVER HAITI...THE NORTHERN
DOMINICAN REPUBLIC AS WELL AS FROM 20N-24N BETWEEN 65W-70W.
UPPER LEVEL DIFFLUENCE OVER THE WESTERN CARIBBEAN FROM AN
INVERTED TROUGH S OF 20N W OF 80W AND THE CYCLONIC CIRCULATION
OVER THE W ATLC IS ENHANCING ISOLATED SHOWERS AND THUNDERSTORMS
N OF 18N W OF 80W. OVER THE SOUTHERN CARIBBEAN SCATTERED
MODERATE CONVECTION IS OCCURRING S OF 14N BETWEEN 77W-83W. THIS
CONVECTION IS ASSOCIATED WITH A 1009 MB LOW OVERLAID THE MONSOON
TROUGH AXIS ACROSS PANAMA. SIMILAR CONVECTION IS WITHIN 60 NM
OFF THE NORTHERN COAST OF COLOMBIA ASSOCIATED WITH A 1007 MB LOW
INLAND. A WEAKNESS IN THE MIDDLE LEVELS COMBINED WITH THE
TRAILING MOISTURE OF THE TROPICAL WAVE AND THE UPPER LEVEL
DIFFLUENCE OVER THE NE CARIBBEAN IS ENHANCING RAINSHOWERS ACROSS
THE VIRGIN ISLANDS FROM 17N-19N BETWEEN 63W-65W.
OTHERWISE...TRADEWINDS OF 15-20 KT SPREAD ACROSS THE BASIN.

A SURFACE TROUGH IS EXPECTED TO ENTER THE EASTERN CARIBBEAN
MONDAY MORNING WITH MINIMUM CONVECTIVE ACTIVITY ASSOCIATED WITH
IT. THE LOW CURRENTLY EMBEDDED WITHIN THE ITCZ IN THE ATLC IS
EXPECTED TO MOVE ACROSS THE LESSER ANTILLES BY TUESDAY MORNING
AND WINDS ARE EXPECTED TO INCREASE TO 25 KT OVER THE CENTRAL
CARIBBEAN. SEE THE SPECIAL FEATURES SECTION FOR MORE INFORMATION
REGARDING THIS LOW.

HISPANIOLA...
A TROPICAL WAVE MOVES ACROSS LA HISPANIOLA THIS EVENING. THIS
WAVE IS EMBEDDED WITHIN A MODERATE MOIST ENVIRONMENT AT THE
LOWER LEVELS AND UPPER LEVEL DIFFLUENCE FROM A CYCLONIC
CIRCULATION OVER THE W ATLC NEAR 24N72W AND AN ANTICYCLONIC
CIRCULATION OVER THE EASTERN CARIBBEAN NEAR 13N65W IS ENHANCING
SCATTERED SHOWERS AND THUNDERSTORMS OVER HAITI...THE NORTHERN
DOMINICAN REPUBLIC AS WELL AS FROM 20N-24N BETWEEN 65W-70W.

THE WAVE IS EXPECTED TO MOVE OFF HAITI TONIGHT AND CONTINUE A W-
NW TRACK TOWARD CUBA. RAINSHOWERS ARE EXPECTED TO CONTINUE TIL
TUESDAY MORNING AS AN UPPER LEVEL DIFFLUENT PATTERN IS EXPECTED
TO PERSIST OVER THE NORTH-CENTRAL CARIBBEAN. CONDITIONS WILL
IMPROVE TUESDAY AFTERNOON AS DRY AIR IS CARRIED OVER THE ISLAND
BY THE SURFACE TROUGH.

ATLANTIC OCEAN...
A NARROW UPPER LEVEL TROUGH IS SUPPORTING A SURFACE TROUGH
REMNANT OF A STATIONARY FRONT FROM 30N42W TO 27N49W 26N57W.
SCATTERED SHOWERS ASSOCIATED TO IT ARE N OF 27N BETWEEN 41W-47W.
A FORMER TROPICAL WAVE ASSOCIATED WITH THE LOW EMBEDDED WITHIN
THE ITCZ IS NOW BEING ANALYZED AS A SURFACE TROUGH ALONG 21N54W
TO 12N56W. THIS TROUGH LIES JUST WEST OF A SAL OUTBREAK AND
THERE IS NO CONVECTION ASSOCIATED WITH IT. OTHERWISE SURFACE
RIDGING AND FAIR WEATHER DOMINATE THE REMAINDER ATLC WATERS.

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

$$
RAMOS


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