[Tropical] Tropical Weather Discussion

[EMWIN Server]

AXNT20 KNHC 221749
TWDAT

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
205 PM EDT MON APR 22 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 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH
1715 UTC.

...ITCZ/MONSOON TROUGH...

THE MONSOON TROUGH EXTENDS FROM THE AFRICAN COAST NEAR 07N12W TO
03N16W. THE INTERTROPICAL CONVERGENCE ZONE AXIS EXTENDS FROM
03N16W TO THE EQUATOR NEAR 25W TO 03N37W TO 02N51W. WIDELY
SCATTERED MODERATE CONVECTION IS FROM 01N-05N  BETWEEN 10W-24W.
ISOLATED MODERATE CONVECTION IS WITHIN 90 NM EITHER SIDE OF A
LINE FROM 03N29W TO 07N52W.

...DISCUSSION...

GULF OF MEXICO...
WATER VAPOR IMAGERY INDICATES GENERALLY WESTERLY MIDDLE TO UPPER
LEVEL FLOW IS OVER THE GULF BASIN THIS AFTERNOON AS WEAK
LONGWAVE MIDDLE TO UPPER LEVEL TROUGHING CONTINUES TO SHIFT
EASTWARD INTO THE SW NORTH ATLC. THIS UPPER LEVEL FEATURE
SUPPORTS SURFACE TROUGHING THAT EXTENDS ACROSS THE FLORIDA
PENINSULA INTO THE SE GULF WATERS GENERATING MULTILAYERED
CLOUDINESS AND ISOLATED SHOWERS ACROSS THE FLORIDA KEYS AND A
PORTION OF THE SE GULF S OF 25N E OF 86W. A SURFACE TROUGH IS
ALSO ANALYZED FROM 25N89W TO THE WESTERN YUCATAN PENINSULA COAST
NEAR 19N91W THAT COTNINUES TO LACK ANY SIGNIFICANT PRECIPITATION
OCCURRING WITHIN ITS VICINITY. THE REMAINDER OF THE NORTHERN AND
WESTERN GULF IS UNDER THE INFLUENCE OF A SURFACE RIDGE WITH AXIS
EXTENDING FROM THE CAROLINAS THROUGH THE MISSISSIPPI RIVER DELTA
REGION TO EAST-CENTRAL MEXICO NEAR 22N98W. MOSTLY FAIR
CONDITIONS EXIST UNDER SCATTERED TO BROKEN LOW-LEVEL CLOUDINESS.
THE SURFACE TROUGHING ACROSS THE SW NORTH ATLC AND SE GULF WILL
SLOWLY DRIFT EAST OF THE BASIN THROUGH EARLY TUESDAY...HOWEVER
THEREAFTER EAST-SOUTHEAST WINDS IN THE RANGE OF 10 TO 20 KT WILL
PREVAIL THROUGH EARLY WEDNESDAY AS THE NEXT WEAK COLD FRONT IS
FORECAST TO EMERGE OFF THE TEXAS AND LOUISIANA COAST MID-DAY
WEDNESDAY.

CARIBBEAN SEA...
OVERALL DRY AND STABLE AIR IN WEST-NORTHWESTERLY FLOW ALOFT
DOMINATES OVER MUCH OF THE CARIBBEAN THIS AFTERNOON KEEPING
CONDITIONS ACROSS THE BASIN FAIRLY TRANQUIL. SATELLITE AND TOTAL
PRECIPITABLE WATER IMAGERY INDICATE A SWATH OF LOWER LEVEL
MOISTURE AND CLOUDINESS EXTENDING FROM THE WINDWARD ISLANDS AND
SE CARIBBEAN NEAR 13N61W TO 14N70W TO 19N75W AND THE SOUTHERN
APPROACHES TO THE WINDWARD PASSAGE. ISOLATED LOW-TOPPED SHOWER
ARE POSSIBLE WITHIN 120 NM EITHER SIDE OF A LINE FROM THE
GRENADINES NEAR 13N61W TO 15N74W...AND N OF 15N BETWEEN 72W-
77W...INCLUDING WESTERN HISPANIOLA AND EASTERN JAMAICA. TRADE
WINDS REMAIN IN THE RANGE OF 10 TO 20 KT THIS AFTERNOON AND ARE
EXPECTED TO PERSIST IN THAT RANGE THROUGH MUCH OF THE WEEK.

ATLANTIC OCEAN...
A MIDDLE TO UPPER LEVEL LONGWAVE TROUGH IS OVER THE SW NORTH
ATLC THAT SUPPORTS A WEAK 1016 MB LOW CENTERED OFF THE FLORIDA
PENINSULA NEAR 29N80W. A WARM FRONT EXTENDS NE FROM THE LOW TO
31N78W WITH THE FRONT BECOMING STATIONARY BEYOND 32N77W. A
SURFACE TROUGH IS ANALYZED SOUTH FROM THE LOW CENTERED ACROSS
THE SOUTHERN PORTION OF THE FLORIDA PENINSULA TO NEAR 25N81W.
WITH A WARM AND STATIONARY FRONT IN PLACE AT THE SURFACE
GENERALLY EAST OF THE MIDDLE TO UPPER LEVEL TROUGHING...
SCATTERED SHOWERS AND TSTMS ARE OCCURRING N OF 27N BETWEEN 72W-
80W IN THE AREA OF MAXIMUM UPPER LEVEL DIFFLUENCE. WIDELY
SCATTERED SHOWERS AND ISOLATED TSTMS ARE OCCURRING FROM 23N-27N
BETWEEN 74W-80W AS THE BASE OF THE TROUGH BEGINS TO SWING N-NE
OVER THE NEXT 12 TO 24 HOURS. THE REMAINDER OF THE SW NORTH ATLC
BETWEEN 50W-72W IS UNDER THE INFLUENCE OF A MIDDLE TO UPPER
LEVEL ANTICYCLONIC CIRCULATION CENTERED NEAR 28N63W THAT
SUPPPORTS SURFACE RIDGING AND OVERALL FAIR CONDITIONS THIS
AFTERNOON. FARTHER EAST...A BROAD AND COMPLEX MIDDLE TO UPPER
LEVEL LOW IS CENTERED NEAR 31N38W THAT SUPPORTS A 1007 MB
SURFACE LOW CENTERED NEAR 29N37W. MOST PRECIPITATION GENERATED
BY THIS SYSTEM IS LOCATED WITHIN THE NE QUADRANT WITH WIDELY
SCATTERED SHOWERS AND ISOLATED TSTMS OCCURRING FROM 27N-34N
BETWEEN 27W-38W.

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

$$
HUFFMAN


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