Atlantic Tropical Weather Discussion

000
AXNT20 KNHC 221745
TWDAT 

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
205 PM EDT WED MAY 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.

...TROPICAL WAVES...                                     
TROPICAL WAVE EXTENDS FROM 01N44W TO 06N42W MOVING W AT 10 KT. 
THE WAVE REMAINS ON THE WESTERN EXTENT OF THE ITCZ IN A BROAD 
AREA OF CYCLONIC TURNING BETWEEN 39W-47W. THIS AREA ALSO 
COINCIDES IN AN AREA OF MAXIMUM TOTAL PRECIPITABLE WATER. 
SCATTERED MODERATE CONVECTION IS WITHIN 120 NM EITHER SIDE OF 
A LINE FROM 06N38W TO 01N46W.

TROPICAL WAVE EXTENDS FROM 08N80W TO 13N78W MOVING W AT 10 TO 15 
KT. AS OF 22/1200 UTC...THE WAVE HAS BEEN RE-POSITIONED FARTHER 
WEST DUE TO FURTHER ANALYSIS OF THE MOVEMENT OF POTENTIAL 
VORTICITY OF THE GFS 315K THETA FIELDS AND LOCATION AND MOVEMENT 
OF GFS AND ECMWF 700 MB TROUGH AXES OVER THE PAST FEW DAYS. 
TOTAL PRECIPITABLE WATER IMAGERY INDICATES HIGHER VALUES OVER 
THE SW CARIBBEAN IN THE VICINITY OF THE WAVE AXIS WITH POSSIBLE 
SCATTERED MODERATE CONVECTION OCCURRING S OF 14N BETWEEN 71W-83W.

...ITCZ/MONSOON TROUGH...                                     
THE MONSOON TROUGH EXTENDS FROM THE AFRICAN COAST NEAR 15N17W TO 
08N22W. THE INTERTROPICAL CONVERGENCE ZONE AXIS EXTENDS FROM 
08N22W TO 04N30W TO 04N42W. WIDELY SCATTERED MODERATE CONVECTION 
IS FROM 02N-06N BETWEEN THE PRIME MERIDIAN AND 09W...AND FROM 
02N-09N BETWEEN 18W-23W.

...DISCUSSION...

GULF OF MEXICO...                                                
BROAD MIDDLE TO UPPER LEVEL RIDGING IS NOTED ACROSS THE GULF W 
OF 85W WITH A WEAK SHORTWAVE TROUGH AXIS PROGRESSING E-NE OVER 
THE LOWER MISSISSIPPI RIVER VALLEY THIS AFTERNOON. THIS 
SHORTWAVE TROUGH ALONG WITH A STATIONARY FRONT ANALYZED FROM 
31N93W TO ALONG THE TEXAS GULF COAST IS GENERATING SCATTERED 
SHOWERS AND WIDELY SCATTERED TSTMS N OF 29N BETWEEN 87W-94W. 
ANOTHER SHORTWAVE TROUGH EXTENDS FROM OVER SOUTHERN GEORGIA S-SE 
OVER THE LENGTH OF THE FLORIDA PENINSULA TO 24N77W. MOST OF THE 
ACTIVE WEATHER WITH THIS UPPER LEVEL FEATURE REMAINS ACROSS THE 
FLORIDA PENINSULA INTO THE SW NORTH ATLC WATERS. OTHERWISE... 
SURFACE RIDGING DOMINATES ACROSS THE BASIN WITH S-SE WINDS IN 
THE RANGE OF 5 TO 15 KT EXPECTED TO PERSIST THROUGH LATE 
THURSDAY.

CARIBBEAN SEA...                                           
MIDDLE TO UPPER LEVEL NORTHWEST FLOW ALOFT IS NOTED ON WATER 
VAPOR IMAGERY W OF 70W ON THE EASTERN PERIPHERY OF AN 
ANTICYCLONIC CIRCULATION CENTERED OVER NICARAGUA NEAR 13N85W. 
SKIES REMAIN MOSTLY CLEAR UNDER THIS UPPER LEVEL REGIME N OF 15N 
W OF 70W WITH E-SE TRADE WINDS PERSISTING IN THE RANGE OF 10 TO 
20 KT. THE EXCEPTION IS SCATTERED SHOWERS AND TSTMS ARE 
OCCURRING ACROSS THE SW CARIBBEAN S OF 15N BETWEEN 70W-83W AS 
THE MONSOON TROUGH IS ANALYZED ALONG 11N NORTH OF PANAMA AND 
ACROSS NORTHERN COSTA RICA. THE TROPICAL WAVE ALONG 79W IS ALSO 
INFLUENCING INCREASE MOISTURE AND PRECIPITATION OVER THE SW 
CARIBBEAN. EAST OF 72W...WEST-SOUTHWESTERLY MIDDLE TO UPPER 
LEVEL WINDS DOMINATE AND CONTINUE TO PROVIDE AN OVERALL 
DIFFLUENT ENVIRONMENT SUPPORTING SCATTERED SHOWERS AND TSTMS 
ACROSS THE EASTERN CARIBBEAN THAT REMAIN EMBEDDED WITHIN THE E-
SE TRADE WIND FLOW. OTHERWISE...EASTERLY TRADES ARE EXPECTED TO 
CONTINUE THROUGH MUCH OF THE REMAINDER OF THE WEEK WITH LITTLE 
CHANGE ON THE SYNOPTIC SCALE.

HISPANIOLA...                                                  
CURRENTLY AN MIDDLE TO UPPER LEVEL TROUGH EXTENDS FROM OVER THE 
FLORIDA PENINSULA AND FAR WESTERN SW NORTH ATLC WATERS SE TO 
OVER PORTIONS OF HISPANIOLA. DIFFLUENCE ALOFT REMAINS MAXIMIZED 
OVER THE ISLAND AND ADJACENT WATERS TO THE EAST WHILE E-SE TRADE 
WINDS PERSIST AT THE SURFACE. A WIDE SWATH OF TOTAL PRECIPITABLE 
WATER IS NOTED ON IMAGERY EXTENDING FROM OVER THE LESSER 
ANTILLES NORTHWEST TO BEYOND THE WINDWARD PASSAGE. WITH 
FAVORABLE UPPER LEVEL DYNAMICS AND PLENTY OF MOISTURE IN 
PLACE... THESE INGREDIENTS ALONG WITH PEAK DAYTIME HEATING AND 
INSTABILITY WILL PROVIDE FOR SCATTERED SHOWERS AND TSTMS THIS 
AFTERNOON AND EVENING.

ATLANTIC OCEAN...                                               
A MIDDLE TO UPPER LEVEL SHORTWAVE TROUGH REMAINS OVER THE 
FLORIDA PENINSULA AND FAR SW NORTH ATLC WATERS W OF 72W THAT 
CONTINUES TO SUPPORT SCATTERED SHOWERS AND TSTMS N OF 22N 
BETWEEN 70W-81W. THIS ACTIVITY IS OCCURRING ON THE WESTERN 
PERIPHERY OF A SURFACE RIDGE ANCHORED BY A 1026 MB HIGH CENTERED 
EAST OF BERMUDA NEAR 31N59W. FARTHER EAST...A CENTRAL ATLC UPPER 
LEVEL TROUGH REMAINS LARGELY NORTH OF THE DISCUSSION AREA WITH 
AXIS ALONG 42W. THE TROUGHING SUPPORTS A STATIONARY FRONT 
ANALYZED INTO THE DISCUSSION AREA NEAR 32N41W AND EXTENDS SW TO 
27N49W. WIDELY SCATTERED SHOWERS ARE OCCURRING OVER THE AREA N 
OF 28N BETWEEN 35W-43W. THE REMAINDER OF THE EASTERN ATLC IS 
UNDER THE INFLUENCE OF A SURFACE RIDGE ANCHORED BY A 1037 MB 
HIGH CENTERED WELL NORTH OF THE AZORES NEAR 50N23W.

NOTE...A GOES-E/GOES-13 ANOMALY OCCURRED LAST NIGHT PRIOR TO 
0400 UTC AND HAS IMPACTED THE FULL SUITE OF IMAGERY AVAILABLE 
FROM THIS SATELLITE...AND IS LIMITING CONFIDENCE IN SATELLITE 
INTERPRETATION ACROSS THE REGION BETWEEN APPROXIMATELY 60W AND 
100W. NESDIS ENGINEERS ARE WORKING ON RECOVERY EFFORTS AT THIS 
TIME. GOES-14 IS BEING ACTIVATED AND THE FIRST IMAGES ARE 
EXPECTED TO BECOME AVAILABLE AROUND 0500 UTC THU MAY 23. 

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

$$
HUFFMAN