000 AXNT20 KNHC 181046 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 805 AM EDT SUN JUN 18 2006 TROPICAL WEATHER DISCUSSION FOR NORTH AMERICA...CENTRAL AMERICA...THE GULF OF MEXICO...THE CARIBBEAN SEA...NORTHEASTERN SECTIONS OF SOUTH AMERICA...AND THE 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1015 UTC. ...TROPICAL WAVES... TROPICAL WAVE IS ALONG 21W S OF 15N MOVING W 15-20 KT. BROAD MID LEVEL CIRCULATION IS OBSERVED ON VISIBLE SATELLITE IMAGERY. NO ASSOCIATED CONVECTION. TROPICAL WAVE IS ALONG 49W S OF 16N MOVING W 15-20 KT. BROAD LOW/MID LEVEL CURVATURE SIGNATURE IS OBSERVED ON VISIBLE SATELLITE IMAGERY. SCATTERED MODERATE/STRONG CONVECTION IS FROM 11N-14N BETWEEN 47W-52W. TROPICAL WAVE IS ALONG 66W/67W S OF 21N MOVING W 10-15 KT. WAVE SIGNATURE CURVATURE REMAINS WEAK AS IT CROSSES THE E CARIBBEAN. WAVE IS BENEATH THE WESTERN EDGE OF AN UPPER RIDGE. NO ASSOCIATED SHOWERS OR CONVECTION. ...ITCZ... ITCZ AXIS IS CENTERED ALONG 11N14W 3N30W 12N47W 6N50W 7N60W.CLUSTERS OF SCATTERED MODERATE/ISOLATED STRONG CONVECTION ARE FROM 2N TO THE COAST OF SW AFRICA E OF 13W ACROSS THE PRIME MERIDIAN AND WITHIN 200 NM OF THE AXIS FROM 20W-47W. CLUSTERS OF SCATTERED MODERATE CONVECTION ARE WITHIN 90 NM OF THE AXIS FROM 47W-57W. ...DISCUSSION... GULF OF MEXICO... MID/UPPER LEVEL TROUGH REMAINS OVER THE CENTRAL US INTO TEXAS AND THE NW GULF N OF 25N W OF 92W. THE DEEP LAYERED TROUGH THAT IS IN THE W ATLC INCLUDES THE E GULF N OF 22N E OF 86W. THIS LEAVES THE REMAINDER OF THE GULF UNDER AN UPPER HIGH LOCATED NEAR 22N91W WITH A SHARP RIDGE AXIS EXTENDING N OVER THE MISSISSIPPI VALLEY. GULF REMAINS QUIET THIS MORNING WITH THE EXCEPTION OF ISOLATED SHOWERS OVER THE SE GULF S OF 25N E OF 85W THROUGH THE STRAITS OF FLORIDA. CARIBBEAN SEA... THE CARIBBEAN IS DOMINATED BY TWO UPPER HIGHS...THE ONE OVER THE GULF OF MEXICO AND THE SECOND OVER THE W TROPICAL ATLC. BROAD UPPER TROUGH OVER THE W ATLC DIPS INTO THE CENTRAL CARIBBEAN N OF 16N FROM 70W-83W. ISOLATED SHOWERS ARE AT THE BASE OF THE UPPER TROUGH EXTENDING ACROSS THE N CARIBBEAN N OF 18N FROM HISPANIOLA THROUGH CUBA. DRY AIR CONTINUES TO DOMINATE MOST OF THE CARIBBEAN WITH THE EXCEPTION OF ISOLATED SHOWERS WITHIN 90 NM ALONG THE COAST OF CENTRAL AMERICA S OF 12N W OF 80W. ATLANTIC OCEAN... BROAD DEEP LAYERED TROUGH CONTINUES TO DIG S ACROSS THE W ATLC INTO THE GULF OF MEXICO AND THE N CENTRAL CARIBBEAN FROM W OF 60W. THE ASSOCIATED SURFACE TROUGH EXTENDS THROUGH 32N63W SW TO 26N71W. DESPITE THE INFLUX OF DRY AIR...SCATTERED SHOWERS ARE AT THE BASE OF THE UPPER TROUGH S OF 28N FROM 63W-83W INCLUDING PORTIONS OF THE FLORIDA PENINSULA. NARROW RIDGE AXIS IS BETWEEN THE W ATLC TROUGH AND A BROAD UPPER LOW CENTERED NEAR 30N35W WITH THE UPPER TROUGH EXTENDING S TO 21N35W. AT THE SURFACE...BROAD HIGH PRESSURE DOMINATES THE REMAINDER OF THE ATLC ANCHORED BY A 1033 MB HIGH WELL N OF THE REGION. THE DEEP TROPICS IS DOMINATED BY AN UPPER HIGH OVER THE W TROPICAL ATLC NEAR 15N48W AND A SECOND RIDGE EXTENDING OFF THE AFRICAN COAST ALONG 16N/17N E OF 30W. DIFFLUENCE ON THE W SIDE OF THE UPPER HIGH IN THE W TROPICAL ATLC IS GENERATING AN AREA OF OVERCAST CLOUDINESS WITH SCATTERED SHOWERS/ISOLATED THUNDERSTORMS FROM 18N-28N BETWEEN 54W-60W. IT APPEARS THAT ANOTHER THIN LAYER OF AFRICAN DUST IS MOVING ACROSS THE E ATLC S OF 20N E OF 40W THUS LIMITING SHOWER ACTIVITY ASSOCIATED WITH THE TROPICAL WAVE ALONG 21W. $$ WALLACE