[Tropical] Tropical Weather Discussion

[EMWIN Server]

AXNT20 KNHC 290549
TWDAT

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
205 AM EDT TUE OCT 29 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 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH
0515 UTC.

...TROPICAL WAVES...
TROPICAL WAVE IS ON THE EASTERN CARIBBEAN WITH AXIS EXTENDING
FROM 17N64W TO 07N59W AND MOVING W NEAR 15 KT. WAVE IS EMBEDDED
WITHIN A MODERATE TO HIGH MOIST ENVIRONMENT AS DEPICTED ON THE
SSMI TOTAL PRECIPITABLE WATER IMAGERY. RAINSHOWERS HAS BEEN
REPORTED IN THE LESSER ANTILLES AS WELL AS IN THE VIRGIN
ISLANDS. HOWEVER...STRONG WESTERLY-NORTHWESTERLY SHEAR IN THIS
REGION OF THE BASIN IS HINDERING DEEP CONVECTION.

...THE ITCZ/THE MONSOON TROUGH...
THE MONSOON TROUGH AXIS EXTENDS ACROSS AFRICA INTO THE E
TROPICAL ATLC NEAR 16N16W AND CONTINUES TO 14N19W. SCATTEROMETER
DATA SUGGEST THERE IS A BREAK BETWEEN THIS AXIS AND THE
ITCZ...WHICH EXTENDS ALONG 06N21W TO 08N40W 05N53W. NUMEROUS
MODERATE CONVECTION IS FROM 07N-10N BETWEEN 28W-35W. SCATTERED
MODERATE CONVECTION IS FROM 06N-18N BETWEEN 17W-27W AND WITHIN
140 NM SOUTH OF THE ITCZ AXIS BETWEEN 37W-44W.

...DISCUSSION...

THE GULF OF MEXICO...
SURFACE RIDGING DOMINATES ACROSS THE GULF WATERS ANCHORED BY A
1025 MB HIGH OVER THE WEST ATLC NEAR 37N70W. SURFACE RIDGING IS
BEING REINFORCED BY A MIDDLE TO UPPER LEVEL RIDGE CENTERED OVER
THE WESTERN BASIN. SSMI TOTAL PRECIPITABLE WATER AND WATER VAPOR
IMAGERY SHOW VERY DRY AIR ACROSS THE GULF WHICH IS SUPPRESSING
CONVECTION...THUS SUPPORTING FAIR WEATHER. IN THE BAY OF
CAMPECHE...A SURFACE TROUGH IS BEING ANALYZED FROM 22N92W TO
13N92W IN THE E PACIFIC. ISOLATED SHOWERS ARE EAST OF THE AXIS S
OF 20N. SURFACE RIDGING IS FORECAST TO PERSIST THROUGH FRIDAY
AFTERNOON. A LOW PRESSURE SYSTEM IS EXPECTED TO DEVELOP OVER THE
SOUTHERN PLAINS WITH A COLD FRONT REACHING THE TEXAS COAST
FRIDAY NIGHT.

CARIBBEAN SEA...
DIFFLUENT FLOW ALOFT FROM A MIDDLE TO UPPER LEVEL TROUGH IN THE
N WESTERN ATLC AND THE RIDGE OVER THE GULF OF MEXICO WHICH
EXTENDS TO THE WESTERN CARIBBEAN SEA IS SUPPORTING ISOLATED
SHOWERS N OF 13N W OF 77W...INCLUDING JAMAICA. IN THE SOUTHERN
BASIN...THE MONSOON TROUGH AXIS EXTENDS FROM SOUTHERN COSTA RICA
TO NORTHERN COLOMBIA AND IS ENHANCING ISOLATED SHOWERS AND TSTMS
SW OF A LINE FROM 14N82W TO 10N78W. IN THE CENTRAL
BASIN...SUBSIDENCE OF VERY DRY AIR SUPPORTS FAIR WEATHER BETWEEN
68W-78W. A TROPICAL WAVE IS ON THE EASTERN CARIBBEAN WITH AXIS
EXTENDING FROM 17N64W TO 07N59W. THE WAVE IS EMBEDDED WITHIN A
MODERATE TO HIGH MOIST ENVIRONMENT AS DEPICTED ON THE SSMI TOTAL
PRECIPITABLE WATER IMAGERY. RAINSHOWERS HAS BEEN REPORTED IN THE
LESSER ANTILLES AS WELL AS IN THE VIRGIN ISLANDS.
HOWEVER...STRONG WESTERLY-NORTHWESTERLY SHEAR IN THIS REGION OF
THE BASIN IS HINDERING DEEP CONVECTION. THE TROPICAL WAVE WILL
CONTINUE A WESTWARD TRACK TO PASS CLOSE TO SOUTHERN PUERTO RICO
TODAY AND THROUGH HISPANIOLA FROM THURSDAY AFTERNOON.

HISPANIOLA...
A MIDDLE TO UPPER LEVEL TROUGH IN THE N WEST ATLC SUPPORTS A
STATIONARY FRONT THAT TRANSITIONS TO A COLD FRONT FROM NE OF THE
CENTRAL BAHAMAS TO CENTRAL CUBA. ISOLATED SHOWERS ASSOCIATED
WITH THIS FRONTAL BOUNDARY EXTENDS ISLANDWIDE AND ACROSS THE
WINDWARD PASSAGE. A MOIST AIRMASS IS EXPECTED TO MOVE ACROSS THE
ISLAND FROM TUESDAY AFTERNOON THROUGH EARLY THURSDAY WHEN A
TROPICAL WAVE IS EXPECTED TO START MOVING ACROSS THE ISLAND.
SHOWERS ARE EXPECTED THROUGH THIS PERIOD.

ATLANTIC OCEAN...
A MIDDLE TO UPPER LEVEL TROUGH IN THE N WEST ATLC SUPPORTS A
STATIONARY FRONT FROM 30N58W TO 25N73W WHERE IT TRANSITIONS TO A
COLD FRONT ACROSS THE CENTRAL BAHAMAS TO CENTRAL CUBA. SCATTERED
MODERATE CONVECTION IS ON THE SOUTHERN BAHAMAS AS WELL AS FROM
23N-36N BETWEEN 60W-71W. THE REMAINDER OF THE ATLC IS DOMINATED
BY A SURFACE RIDGE THAT IS ANCHORED BY A STRONG 1032 MB HIGH N
OF THE DISCUSSION AREA NEAR 40N23W. THE PORTION OF THE FRONT
THAT IS STATIONARY IS EXPECTED TO TRANSITION TO A COLD FRONT
WITH A SHEAR LINE EXTENDING ACROSS THE BAHAMAS THROUGH THURSDAY
AFTERNOON.

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

$$
NR


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