000 AXNT20 KNHC 072353 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 805 PM EDT WED 07 APR 2004 TROPICAL WEATHER DISCUSSION FOR NORTH AMERICA...CENTRAL AMERICA...GULF OF MEXICO...CARIBBEAN SEA...AND ATLANTIC OCEAN TO THE AFRICAN COAST FROM THE EQUATOR TO 32N INCLUDING NORTHERN SECTIONS OF SOUTH AMERICA. THE FOLLOWING INFORMATION IS BASED ON SATELLITE IMAGERY...WEATHER OBSERVATIONS...RADAR...AND METEOROLOGICAL ANALYSIS. THE TROPICAL ANALYSIS AND FORECAST BRANCH OF THE NATIONAL HURRICANE CENTER/TROPICAL PREDICTION CENTER IS CONSIDERING CHANGING THE FORMAT OF THIS PRODUCT. A SUMMARY OF THE PROPOSED CHANGES AND AN EXAMPLE ARE POSTED AT THE FOLLOWING WEB ADDRESS: WWW.NHC.NOAA.GOV/NEWTWDFORMAT.SHTML (ALL LOWER CASE). THE EVALUATION PERIOD WILL END APRIL 30 2004. DURING THIS PERIOD WE ENCOURAGE YOUR COMMENTS OR SUGGESTIONS FOR IMPROVEMENTS. A LINK TO A FEEDBACK FORM IS AVAILABLE ON THE WEB SITE GIVEN ABOVE. YOUR FEEDBACK WILL HELP US TO DETERMINE PRODUCT QUALITY...IF MODIFICATIONS ARE NEEDED...AND WHETHER THE PROPOSED CHANGES WILL BE ADOPTED. IN QUESTION 8 OF THE SURVEY...PLEASE STATE THAT YOU ARE A USER OF THE ATLANTIC TROPICAL WEATHER DISCUSSION...AND WHETHER YOU PREFER THE OLD OR THE PROPOSED NEW VERSION. BASED ON 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 2315 UTC. SPECIAL FEATURES... NONE. TROPICAL WAVES/ITCZ... AXIS OF ITCZ-RELATED CLOUDS/CONVECTION IS CENTERED ALONG 8N1W 2N35W EQ. SCATTERED STRONG CONVECTION OVER W AFRICA FROM 5N-10N BETWEEN 1W-10W. SCATTERED MODERATE CONVECTION S OF 4N BETWEEN 30W-50W. MIDDLE/UPPER LEVEL SYNOPTIC FEATURES... GULF OF MEXICO... STRONG SHORTWAVE TROUGH MOVING EWD OVER THE S UNITED STATES CLIPS THE N PORTION OF THE GLFMEX PRODUCING AN AREA OF SHOWERS/THUNDERSTORMS OVER THE NE GLFMEX SPREADING EWD TOWARD N FLORIDA. FURTHER W...MID/UPPER LEVEL TROUGH IS DIGGING SWD OVER THE SW UNITED STATES AND E PACIFIC WITH ATTENDANT 120 KT SUBTROPICAL JET EXTENDING ACROSS CENTRAL MEXICO AND THE N GULF COAST TO CUBA. COPIOUS MID/UPPER LEVEL MOISTURE ACCOMPANIES THE JET AND CONTINUES TO SPILL EWD INTO THE GLFMEX. WATER VAPOR IMAGERY SHOWS THE SW UNITED STATES TROUGH IS AMPLIFYING AS IT PROGRESSES EWD ALLOWING RIDGING TO DEVELOP OVER MEXICO. THIS RIDGE WILL EVENTUALLY MOVE EWD INTO THE GLFMEX DURING THE NEXT 24-36 HRS PUSHING THE SUBTROPICAL JET AND THE BULK OF THE UPPER DYNAMICS/LIFT JUST N OF THE AREA OVER THE S UNITED STATES. CARIBBEAN... FAIRLY STATIONARY PATTERN CONTINUES OVER THE CARIBBEAN WITH A BROAD/FLAT RIDGE REMAINING OVER S AMERICA 5N/6N. SUBTROPICAL JET CONTINUES TO FLOW AROUND THE N PERIPHERY OF THE RIDGE KEEPING MOST OF THE UPSTREAM MOISTURE ADVECTION N OF THE AREA. THE ONE EXCEPTION LIES OVER THE NW CARIBBEAN WHERE THE JET AND ASSOCIATED MOISTURE CLIPS THE AREA NW OF A LINE FROM BELIZE TO E CUBA. MID/UPPER LEVEL SUBSIDENCE PREVAILS ELSEWHERE WITH SHOWERS/THUNDERSTORMS REMAINING ISOLATED AND PRIMARILY CONFINED TO AFTERNOON ACTIVITY OVER LAND. ATLANTIC... NEAR ZONAL FLOW CONTINUES ACROSS MUCH OF THE W ATLC WITH A SERIES OF SHORTWAVES CLIPPING THE AREA N OF 25N. THE FIRST OF THESE SHORTWAVES IS MOVING ACROSS THE SE UNITED STATES CASTING MID/UPPER LEVEL CLOUDINESS OVER THE ATLC W OF 70W. FURTHER E...A MUCH MORE ACTIVE DISTURBANCE...LOCATED ALONG 32N55 25N70W...IS PRODUCING INCREASING SHOWERS/THUNDERSTORMS ALONG A PERSISTENT SURFACE TROUGH FROM 31N45W TO 20N60W. MODERATE SUBSIDENCE ON THE BACKSIDE OF THE SHORTWAVE COVERS THE AREA TO 70W. MID/UPPER LEVEL RIDGE OVER THE CENTRAL ATLC EXTENDS NWD FROM A ANTICYCLONE NEAR 7N55W TO BEYOND 31N35W. FURTHER E...TROUGH OVER THE E ATLC EXTENDS SWD FROM THE CANARY ISLANDS TO 12N40W. ATTENDANT JET EXTENDS FROM THE CAPE VERDE ISLANDS NEWD INTO W AFRICA. MODERATE SUBSIDENCE WITH THIS FEATURE EXTENDS WELL INTO THE TROPICAL ATLC N OF THE ITCZ. TROUGH ALSO SPLITS A RIDGE EXTENDING WEST FROM AFRICA ALONG 10N E OF 20W. RIDGE RESUMES W OF 35W WITH A ANTICYCLONE NEAR 7N55W. SURFACE SYNOPTIC FEATURES... TROUGH OVER THE NW GLFMEX EXTENDS FROM LOUISIANA TO TAMPICO MEXICO. NO SIGNIFICANT CLOUDS/CONVECTION. 1018 MB HIGH IS LOCATED OVER THE W ATLC JUST NE OF THE BAHAMAS NEAR 28N73W WITH RIDGE AXIS EXTENDING SW ACROSS S FLORIDA INTO THE CENTRAL GLFMEX NEAR 25N92W. TROUGH OVER THE CENTRAL ATLC ENTERS THE AREA NEAR 31N45W SW ALONG 25N54W TO 20N60W. SCATTERED MODERATE CONVECTION N OF 24N BETWEEN 43W-52W. 1020 MB HIGH IS LOCATED OVER THE E ATLC NEAR 28N34W WITH RIDGE AXIS EXTENDING SW TO 19N50W. SIGNIFICANT CLOUDS/CONVECTION... GULF OF MEXICO... WIDELY SCATTERED TO LOCALLY SCATTERED MODERATE CONVECTION OVER THE NE GLFMEX E OF 85W TO THE COAST OF FLORIDA AND ELSEWHERE N OF 28N E OF 91W. STRONGEST AND MOST NUMEROUS ACTIVITY IS CURRENTLY ALONG THE COAST OF FLORIDA WEST APALACHICOLA. CARIBBEAN SEA... NONE SIGNIFICANT. TROPICAL ATLANTIC.. SEE ITCZ. SUBTROPICAL ATLANTIC... SCATTERED MODERATE CONVECTION N OF 24N BETWEEN 43W-52W. $$ RHOME