| HOME | ARCHIVES | FORECASTS | IMAGERY | ABOUT NHC | RECONNAISSANCE |

---

Atlantic Tropical Weather Discussion (Text)

000
AXNT20 KNHC 280559
TWDAT 

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
205 AM EDT MON JUL 28 2014

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
0545 UTC.

...TROPICAL WAVES...                                     

TROPICAL WAVE IS OVER THE CENTRAL ATLC WATERS WITH AXIS EXTENDING 
FROM 18N38W TO 9N36W MOVING W AT 10-15 KT DURING THE PAST 24 
HOURS. THE NORTHERN WAVE ENVIRONMENT CONTINUES EMBEDDED IN THE 
DRY SAHARAN AIR LAYER WHICH IS INHIBITING CONVECTION N OF 13N. 
SOUTH OF 13N...THE SSMI TPW IMAGERY SHOW THE WAVE IS IN A DEEP 
LAYER MOIST ENVIRONMENT WHICH ALONG UPPER-LEVEL DIFFLUENCE IS 
SUPPORTING SCATTERED MODERATE CONVECTION FROM 6N-13N BETWEEN 29W-
40W. GRADUAL DEVELOPMENT OF THIS WAVE IS POSSIBLE BY THE MIDDLE 
OF THE WEEK AS ENVIRONMENTAL CONDITIONS BECOME MORE FAVORABLE. 
SEE LATEST NHC TROPICAL WEATHER OUTLOOK UNDER AWIPS/WMO HEADERS 
MIATWOAT/ABNT20 KNHC FOR MORE DETAILS.

TROPICAL WAVE IS OVER THE WESTERN CARIBBEAN WITH AXIS EXTENDING 
FROM 19N81W TO 9N81W MOVING W AT 20-25 KT IN THE PAST 24 HOURS. 
THE WAVE IS ASSOCIATED WITH DEEP LAYER MOISTURE S OF 17N WHERE 
UPPER-LEVEL DIVERGENCE SUPPORT WIDELY SCATTERED MODERATE 
CONVECTION AND ISOLATED TSTMS W OF 75W. 

...ITCZ/MONSOON TROUGH...                                     

THE MONSOON TROUGH EXTENDS FROM THE COAST OF WEST AFRICA NEAR 
12N16W AND THEN CONTINUES ALONG 9N23W TO 9N33W. THE 
INTERTROPICAL CONVERGENCE ZONE AXIS EXTENDS FROM 8N39W TO 4N52W. 
SCATTERED MODERATE CONVECTION AND TSTMS ASSOCIATED WITH THE NEXT 
TROPICAL WAVE TO COME OFF THE AFRICAN COAST IS FROM 5N-12N E OF 
17W. THE OTHER AREA OF CONVECTION IS ASSOCIATED WITH THE TROPICAL 
WAVE OVER THE CENTRAL ATLC. SEE ABOVE FOR DETAILS.

...DISCUSSION...

GULF OF MEXICO...                                               

EXCEPT FOR THE FLORIDA PENINSULA AND EASTERN BAY OF 
CAMPECHE...MOSTLY DRY AIR IS ACROSS THE BASIN AT THE LOWER 
LEVELS AND UPPER LEVELS. ALOFT...THE SE PERIPHERY OF A RIDGE 
ANCHORED OVER TEXAS EXTENDS INTO THE GULF AND SUPPORT A 1020 MB 
HIGH NEAR 27N88W WHICH IS PROVIDING VARIABLE WINDS OF 5-15 KT 
BASIN-WIDE. AN UPPER-LEVEL CYCLONIC CIRCULATION IS OVER THE SW 
GULF SUPPORTING A SURFACE TROUGH ALONG 21N89W TO 16N93W WITH 
SCATTERED SHOWERS AND TSTMS S OF 20N E OF 94W. ELSEWHERE...AN 
OVERALL STABLE ENVIRONMENT SUPPORTS CLEAR SKIES. SURFACE RIDGING 
WILL PREVAIL ACROSS MUCH OF THE GULF THE NEXT TWO DAYS. A COLD 
FRONT WILL BE ENTERING THE NE GULF TUE MORNING AND THEN 
DISSIPATE AS A STATIONARY FRONT WED MORNING.

CARIBBEAN SEA...                                               

THE AXIS OF A TROPICAL WAVE IS ALONG 82W. THIS WAVE IS 
ASSOCIATED WITH DEEP LAYER MOISTURE WHICH IS ENHANCING 
CLOUDINESS ACROSS GREAT PORTIONS OF THE CENTRAL AND WESTERN 
BASIN. IN ADDITION...THE WAVE SUPPORTS WIDELY SCATTERED MODERATE 
CONVECTION OVER THE SW BASIN AS WELL AS TRADES OF 20-25 KT S OF 
17N BETWEEN 69W-81W. SEE TROPICAL WAVE SECTION FOR MORE DETAILS. 
A MID-UPPER LEVEL ANTICYCLONE ANCHORED OVER TEXAS EXTENDS A 
RIDGE AXIS SE ACROSS THE BAHAMAS. FARTHER EAST...AN UPPER-LEVEL 
LOW CENTERED NEAR 22N62W IS GENERATING DIFFLUENT FLOW ALOFT OVER 
THE NORTHERN CARIBBEAN TO SUPPORT ISOLATED SHOWERS OVER CUBA AND 
HISPANIOLA. CLEAR SKIES AND TRADES OF 10-15 KT DOMINATE 
ELSEWHERE ACROSS THE BASIN. THE TROPICAL WAVE WILL MOVE OUT OF 
THE BASIN MON NIGHT THROUGH TUE MORNING. 

...HISPANIOLA...                                                

CURRENTLY...A DIFFLUENT ENVIRONMENT GENERATED BY THE SE 
PERIPHERY OF A RIDGE ANCHORED OVER TEXAS AND AN UPPER LOW OVER 
THE SW N ATLC ENHANCES ISOLATED SHOWERS ACROSS THE ISLAND. 
EXCEPT FOR AFTERNOON/EARLY EVENING SHOWERS BEING ENHANCED BY 
DAYTIME HEATING...FAIR WEATHER CONDITIONS ARE FORECAST THROUGH 
EARLY WED.

ATLANTIC OCEAN...                                              

A MID-UPPER LEVEL LOW CENTERED NEAR 23N63W CONTINUES TO SUPPORT 
SHOWERS AND TSTMS FROM 20N-28N BETWEEN 56W-70W. OVER THE E 
ATLC...A MID-UPPER LEVEL LOW N OF THE AREA CONTINUE TO SUPPORT A 
FRONTAL BOUNDARY ANALYZED AS A DISSIPATING STATIONARY FRONT FROM 
30N29W SW TO 26N37W WITH NO CONVECTION ASSOCIATED WITH IT. THE 
REMAINDER BASIN IS FAIRLY DRY AND UNDER THE INFLUENCE OF SURFACE 
RIDGING ANCHORED BY A 1025 MB HIGH NEAR 32N54W AND A 1025 MB 
HIGH NEAR 34N43W. THESE TWO FACTORS SUPPORTS FAIR WEATHER 
ELSEWHERE IN THE BASIN. OTHERWISE...SEE ABOVE THE TROPICAL WAVES 
SECTION. SURFACE RIDGING WILL DOMINATE ACROSS THE CENTRAL AND 
EASTERN ATLC THE NEXT TWO DAYS. A FRONTAL BOUNDARY IS EXPECTED 
TO MOVE ACROSS THE SW N ATLC BY TUE NIGHT AND WED MORNING. 

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

$$
NR