000 AXNT20 KNHC 061730 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 105 PM EST SAT DEC 06 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 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1715 UTC. ...THE ITCZ/THE MONSOON TROUGH... THE MONSOON TROUGH EXTENDS ACROSS AFRICA INTO THE E TROPICAL ATLC NEAR 11N15W TO 9N19W WHERE THE ITCZ BEGINS AND CONTINUES ALONG 5N30W TO 4N45W. ISOLATED MODERATE CONVECTION IS FROM 5N TO 10N BETWEEN 12W AND 18W. SCATTERED MODERATE AND ISOLATED STRONG CONVECTION IS WITHIN 100 NM OF A LINE FROM 2N31W TO 7N21W. ...DISCUSSION... GULF OF MEXICO... A NARROW UPPER TROUGH EXTENDS OVER THE TENNESSEE VALLEY AND ACROSS THE CENTRAL GULF THAT SUPPORTS A COLD FRONT THAT IS CROSSING TX AND ABOUT TO ENTER THE NW GULF. SCATTERED SHOWERS ARE WITHIN 50 NM AHEAD OF THE FRONT INCLUDING ALONG AND NW OF A LINE FROM 30N92W TO 27N93W. WEAKENING STEERING FLOW OVER THE N GULF IS RESULTING IS LIGHT AND VARIABLE WINDS. E TO NE WINDS OF 10 TO 15 KT COVER THE S GULF. LOW LEVEL MOISTURE SUPPORTS DISORGANIZED SHOWERS FROM 23N TO 28N BETWEEN 82W TO 89W. OVER THE NEXT 24 HOURS THE COLD FRONT WILL CROSS THE NORTHERN GULF WITH SCATTERED SHOWERS POSSIBLE ALONG AND AHEAD OF THE FRONT. CARIBBEAN SEA... A BROAD UPPER RIDGE EXTENDS FROM THE E PACIFIC NORTHWARD ACROSS THE SW CARIBBEAN TO CUBA. THIS RIDGE CONTINUES TO DOMINATE THE CARIBBEAN. DRY AIR ALOFT AND SUBSIDENCE COVERS THE NW AND CENTRAL CARIBBEAN N OF 15N. THE MONSOON TROUGH OVER PANAMA CONTINUES TO PRODUCE SCATTERED MODERATE CONVECTION TO 13N BETWEEN 74W AND 84W. OVER THE EASTERN CARIBBEAN...A SURFACE TROUGH OVER THE CENTRAL ATLANTIC EXTENDS SOUTHWARD OVER THE VIRGIN ISLANDS TO 15N64W. SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS ARE WITHIN 200 NM OF THIS TROUGH. OVER THE NEXT 24 HOURS THE SURFACE TROUGH WILL LIFT NE OF THE EASTERN BASIN. CONVECTION WILL CONTINUE OVER THE SW BASIN. HISPANIOLA... NORTHEASTERLY FLOW AROUND A LARGE AREA OF LOW PRESSURE IN THE CENTRAL ATLANTIC PERSISTS ACROSS THE ISLAND TODAY. OTHER THAN ISOLATED SHOWERS DUE TO UPSLOPE WINDS...DRY CONDITIONS ARE EXPECTED OVER THE ISLAND THROUGH SUNDAY. ATLANTIC OCEAN... AN UPPER RIDGE IS OVER THE FAR WESTERN ATLANTIC. UNDERNEATH THIS RIDGE...A WEAKENING STATIONARY FRONT REMAINS FROM 31N79W TO THE FL COAST NEAR 30N81W. DISSIPATING FOG AND ISOLATED SHOWERS ARE WITHIN 50 NM OF THIS FRONT. DOWNSTREAM OF THE RIDGE IS A CUTOFF UPPER LOW CENTERED NEAR 24N60W. THIS LOW HAS BECOME STACKED NEARLY VERTICALLY WITH A SURFACE LOW CENTERED NEAR 26N60W. A SURFACE TROUGH EXTENDS THROUGH THE SURFACE LOW FROM 31N59W TO 18N62W AND OVER THE E CARIBBEAN. SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS ARE WITHIN 100 NM OF THE TROUGH AXIS. A BROAD AREA OF SCATTERED MODERATE CONVECTION IS FROM 15N TO 31N BETWEEN 48W AND 59W. FARTHER EAST...A WEAK SURFACE TROUGH EXTENDS FROM 21N46W TO 17N46W. THIS TROUGH IS MOVING TOWARD THE LARGER SYSTEM IN THE CENTRAL ATLANTIC AND WILL LIKELY BE ABSORBED SOON. NO DEEP CONVECTION IS ASSOCIATED WITH THIS TROUGH. IN THE EASTERN ATLANTIC...AN UPPER TROUGH EXTENDS N TO S ALONG 31W. A BROAD AREA OF CLOUD COVER AND EMBEDDED SHOWERS IS EAST OF THE TROUGH AXIS FROM 10N TO 23N BETWEEN THE AFRICAN COAST AND 27W. THE LOW IN THE CENTRAL ATLANTIC WILL BE MOSTLY STATIONARY THROUGH TONIGHT BEFORE BEGINNING TO TRACK NE ON SUNDAY. CONVECTION WILL CONTINUE WITHIN SEVERAL HUNDRED MILES OF THIS LOW. A COLD FRONT WILL ENTER THE W ATLANTIC FROM THE CONUS ON SUNDAY. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ LATTO