[Tropical] Tropical Weather Discussion

[EMWIN Server]

AXNT20 KNHC 232348
TWDAT

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
805 PM EDT WED MAY 23 2012

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...

TROPICAL WAVE EXTENDS FROM 04N32W TO 12N31W MOVING W AT 15-20
KT. THE WAVE COINCIDES WITH A SURGE OF DEEP LAYER MOISTURE NOTED
IN TOTAL PRECIPITABLE WATER IMAGERY. THERE IS A LACK OF DEEP
CONVECTION IN THE VICINITY OF THE WAVE LIKELY DUE TO SAHARAN
DUST NORTH AND WEST OF THE WAVE AXIS.

TROPICAL WAVE EXTENDS FROM 06N54W TO 13N52W MOVING W AT 10-15
KT. OVER THE PAST 24 TO 36 HOURS...THE WAVE INTERACTED WITH AN
UPPER LEVEL TROUGH THAT IS NOW EAST OF THE WAVE AXIS. WHILE
LOWER TO MIDDLE LEVEL ENERGY ASSOCIATED WITH THE WAVE PEELED OFF
TO THE NORTHEAST...PARTIAL LEFTOVER ENERGY CONTINUES WESTWARD AS
SATELLITE IMAGERY SHOWS WIDELY SCATTERED SHOWERS AND ISOLATED
MODERATE CONVECTION REMAINING SOUTH OF 10N BETWEEN 49W-57W. SOME
OF THIS LOWER TO MIDDLE LEVEL MOISTURE IS FORECAST TO IMPACT NE
VENEZUELA AND THE WINDWARD ISLANDS OVER THE UPCOMING WEEKEND.

...ITCZ/MONSOON TROUGH...

THE MONSOON TROUGH EXTENDS FROM THE AFRICAN COAST NEAR 08N13W TO
04N16W TO 03N24W. THE INTERTROPICAL CONVERGENCE ZONE AXIS
EXTENDS FROM 02N33W TO THE EQUATOR NEAR 36W. SCATTERED STRONG
CONVECTION IS FROM 05N-10N BETWEEN 09W-16W. WIDELY SCATTERED
MODERATE CONVECTION IS FROM 03N-07N BETWEEN 18W-23W.

...DISCUSSION...

GULF OF MEXICO...
BROAD UPPER LEVEL TROUGHING IS NOTED ON WATER VAPOR IMAGERY THIS
EVENING ACROSS THE GULF BASIN WITH A MORE AMPLIFIED MIDDLE TO
UPPER LEVEL TROUGH AXIS EXTENDING FROM AN UPPER LEVEL LOW
CENTERED OVER NORTHERN ALABAMA TO A BASE NEAR 26N98W. WEST TO
SOUTHWESTERLY FLOW ALOFT DOMINATES EAST OF THIS TROUGH AXIS...
HOWEVER MUCH OF THIS FLOW IS COMPRISED OF VERY DRY AIR. WITH
VERY LITTLE MOISTURE IN PLACE CURRENTLY OR ADVECTION OF
SIGNIFICANT MOISTURE...AT THE SURFACE...A WEAK 1014 MB HIGH
CENTERED NEAR 27N88W HOLDS STRONG ACROSS THE BASIN AS SATELLITE
IMAGERY INDICATES VERY CLEAR SKIES. LIGHT ANTICYCLONIC WINDS
SURROUND THE HIGH WITH S-SE RETURN FLOW WINDS IN THE RANGE OF 10
TO 20 KT OBSERVED W OF 92W. THE SURFACE RIDGE IS EXPECTED TO
SLIDE NORTHWARD TO THE SE CONUS BY THE WEEKEND LEAVING MOSTLY
MODERATE E-SE WINDS THAT WILL PERSIST THROUGH EARLY MONDAY.

CARIBBEAN SEA...
A NARROW SWATH OF UPPER LEVEL DIFFLUENT FLOW ASSOCIATED WITH AN
UPPER LEVEL RIDGE AXIS EXTENDS FROM OVER NICARAGUA AND HONDURAS
NEAR 14N86W NE ACROSS CUBA AND INTO THE SW NORTH ATLC WATERS.
WITH AN UPPER LEVEL TROUGH SWEEPING ACROSS THE NW GULF OF MEXICO
WATERS...PLENTY OF MIDDLE TO UPPER LEVEL MOISTURE IS ADVECTING
NORTHEASTWARD. THIS ALONG WITH A SURFACE TROUGH ANALYZED FROM
WESTERN CUBA NEAR 23N82W TO A 1009 MB LOW CENTERED NEAR 21N83W
TO 16N86W IS PROVIDING FOCUS FOR SCATTERED SHOWERS AND TSTMS
MAINLY EAST OF THE SURFACE TROUGH AXIS WITHIN 180 NM EITHER SIDE
OF A LINE FROM 22N78W TO 13N86W OVER INTERIOR NICARAGUA. THIS
AREA OF ACTIVE CONVECTION AND WIDESPREAD RAINFALL HAS PERSISTED
FOR THE LAST FEW DAYS ACROSS CUBA AND THE LIKELIHOOD OF FLASH
FLOODING AND POTENTIAL MUDSLIDES REMAINS HIGH. THE SURFACE LOW
IS EXPECTED TO CONTINUE LIFTING NORTHEASTWARD OVER THE NEXT 24
TO 36 HOURS WITH SURFACE TROUGHING DAMPENING OUT OVER THE NW
CARIBBEAN AND YUCATAN CHANNEL BY THE WEEKEND. EAST-SOUTHEAST
TRADES CURRENTLY W OF 78W WILL GRADUALLY SLIDE WESTWARD BY
FRIDAY AS A HIGH PRESSURE RIDGE BUILDS IN FROM THE EAST-
NORTHEAST FROM THE CENTRAL ATLC. FARTHER EAST...LOW-LEVEL
MOISTURE IS ON THE INCREASE S OF 15N E OF 64W WITH ISOLATED
SHOWERS AND TSTMS OCCURRING ACROSS THE WINDWARD ISLANDS AND NE
VENEZUELA. AN APPROACHING TROPICAL WAVE ALONG 53W WILL HELP TO
PROMOTE HIGHER PRECIPITATION CHANCES OVER THE WEEKEND.

ATLANTIC OCEAN...
DIFFLUENCE ALOFT BETWEEN AN UPPER LEVEL TROUGH OVER THE EASTERN
CONUS AND AN UPPER LEVEL RIDGE EXTENDING FROM THE WESTERN
CARIBBEAN SEA TO AN UPPER LEVEL ANTICYCLONIC CIRCULATION NEAR
24N62W IS SUPPORTING A BROAD AREA OF SCATTERED SHOWERS AND
ISOLATED TSTMS ACROSS CENTRAL AND EASTERN CUBA STRETCHING NE
ACROSS MUCH OF THE SW NORTH ATLC FROM 21N-32N BETWEEN 68W-79W.
THE UPPER LEVEL RIDGE CIRCULATION SUPPORTS BROAD SURFACE RIDGING
ANCHORED BY A 1028 MB HIGH CENTERED NEAR 35N45W. HOWEVER...AN
UPPER LEVEL TROUGH OVER THE EASTERN NORTH ATLC EXTENDS SOUTHWARD
INTO THE DISCUSSION AREA AND SUPPORTS A STATIONARY FRONT
ANALYZED ALONG 32N22W TO 29N30W TO 28N40W TO 30N48W. ISOLATED
SHOWERS ARE OCCURRING WITHIN 75 NM EITHER SIDE OF THE FRONT. AN
UPPER LEVEL RIDGE COVERS THE EASTERN TROPICAL ATLC CENTERED NEAR
16N22W. VISIBLE SATELLITE IMAGERY ALONG WITH GOES-R DUST
ENHANCEMENT IMAGERY INDICATES THAT AN AREA OF SAHARAN DUST
EXTENDS FROM THE COAST OF AFRICA TO 50W WITH CLEARING AROUND THE
TROPICAL WAVE ALONG 32W.

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

$$
HUFFMAN




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