000 AXNT20 KNHC 161130 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 705 AM EST FRI FEB 16 2007 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... METEOROLOGICAL ANALYSIS...WEATHER OBSERVATIONS...AND RADAR. BASED ON 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1115 UTC. ...THE ITCZ... ITCZ AXIS IS CENTERED ALONG 6N10W 3N25W 2N30W...CROSSING THE EQUATOR NEAR 35W...1S39W INTO NORTHEASTERN BRAZIL NEAR 2S45W. CLUSTERS OF SCATTERED MODERATE CONVECTION ARE WITHIN 90 NM EITHER SIDE OF THE AXIS BETWEEN 15W-28W. ISOLATED MODERATE IS WITHIN 120 NM N OF THE AXIS W OF 34W. ...DISCUSSION... THE GULF OF MEXICO... THE FRONTAL BOUNDARY THAT BROUGHT THE CONSIDERABLY COOLER AIRMASS TO THE REGION APPEARS TO BE ON THE MOVE ONCE AGAIN AFTER BEING QUASI-STATIONARY FOR THE PAST 12-24 HOURS. AS OF 09 UTC...THE COLD FRONT WAS ANALYZED FROM THE STRAITS OF FLORIDA ACROSS THE YUCATAN PENINSULA ALONG 24N81W 21N88W 19N91W. THE BOUNDARY IS BROKEN IN THE BAY OF CAMPECHE AND THEN CONTINUES STATIONARY NWD ALONG THE E SLOPES OF THE SIERRA MADRE MOUNTAINS TO 25N101W...CLEARLY DEFINED BY THICK LOW CLOUDS. A DENSE LOW TO MID LEVEL CLOUD DECK IS LINGERING BEHIND THE COLD FRONT WITHIN 240 NM. ISOLATED LIGHT SHOWERS ARE EMBEDDED IN THIS REGION AS INDICATED BY DOPPLER RADAR. THESE SHOWERS ARE A LITTLE MORE ORGANIZED IN CENTRAL FLORIDA. THIS AREA IS FAVORED FOR MORE PRECIP DUE TO A THIN LINE OF MOISTURE ALOFT WHICH IS ADVECTED FROM THE EPAC BY A SUBTROPICAL JET. THE JET LIES BETWEEN A DIGGING TROUGH OVER MUCH OF THE CENTRAL/ERN U.S. AND A STRONG RIDGE ANCHORED IN THE PAC S OF MEX. HOWEVER...THE BIG STORY IS THE STRONG NLY SFC WINDS WITH A GALE WARNING IN EFFECT S OF 23N W OF 90W. THESE STRONG WINDS ARE BEING GENERATED BY A TIGHT PRES GRADIENT THAT HAS SET UP BETWEEN THE FRONT AND A 1033 MB HIGH OVER NE TX. THE GALE FORCE WINDS ARE NOT EXPECTED TO LAST MUCH LONGER AS THE STRONG HIGH QUICKLY TRACKS SWD WEAKENING THE GRAD. NWP MODELS PREDICT STRONG NLY WINDS TO BUILD BACK THIS WEEKEND BEHIND THE NEXT COLD FRONT. THE CARIBBEAN SEA... A VERY BROAD STRONG UPPER LEVEL RIDGE STRETCHES ACROSS THE REGION SUPPLYING AN ABUNDANT AMOUNT OF DRY AIR/SUBSIDENT FLOW ALOFT SUPPRESSING ANY SIGNIFICANT TSTM ACTIVITY. THE DRIEST AIR IS S OF 15 E OF 75W WHERE UPPER CONFLUENCE IS STRONGEST BETWEEN TWO UPPER HIGHS EMBEDDED WITHIN THE BROAD RIDGE. BENEATH THE STRONG MID LEVEL CAP...SMALL PATCHES OF LOW-LEVEL MOISTURE ARE BEING STEERED BY MODERATE ELY TRADES E OF 80W. THESE WINDS LIGHTEN AND VEER TO THE S W OF THERE IN RESPONSE TO THE SLOW MOVING FRONTAL BOUNDARY IN THE S GULF. LOW TO MID LEVEL CLOUDS ARE BUILDING SWD WITH THE FRONT AND BEGINNING TO COVER PARTS OF THE YUCATAN PENINSULA AND CHANNEL. THIS FRONT IS EXPECTED TO PUSH INTO THE NW CARIB TODAY EVENTUALLY BECOMING DIFFUSE ON SAT. AS THE FRONT SAGS INTO THE REGION...LOW-LEVEL MOISTURE WILL BE ON THE INCREASE AND SFC WINDS WILL TURN TO THE N-NE AND RAMP UP AS THE PRES GRAD TIGHTENS. THE ATLANTIC OCEAN... A SLOW MOVING COLD FRONT ENTERS THE AREA NEAR 32N62W AND CONTINUES SW ALONG 28N70W 25N77W THEN ACROSS THE STRAITS OF FLA. WHILE DEEP MOISTURE APPEARS RATHER MINIMAL ALONG THE FRONT S OF 32N...FAIRLY DENSE LOW TO MID LEVEL CLOUDS...OVERRUNNING MOISTURE...EXISTS BEHIND THE BOUNDARY WITH EMBEDDED ISOLATED SHOWERS LIKELY. CURRENTLY THE NRN PART OF THE FRONT DOES NOT HAVE MUCH UPPER LEVEL SUPPORT WITH THE FLOW MAINLY ZONAL OR SWLY. HOWEVER...IT IS ON THE WAY AS A DIGGING TROUGH OVER THE ERN U.S. NEARS. THE SFC PATTERN ACROSS THE REMAINDER OF THE ATLC IS DOMINATED BY A 1026 MB HIGH PRES SYSTEM CENTERED NEAR 35N36W. THIS IS SUPPLYING MOSTLY FAIR WEATHER AND MODERATE TRADES ACROSS A GOOD PORTION OF THE CENTRAL AND E ATLC. THE MID AND UPPER LEVEL PATTERN IS PRETTY BENIGN ACROSS MOST OF THE DISCUSSION AREA WITH NW-WLY FLOW COMMON EXCEPT FOR THE NE CORNER WHERE THE SRN BRANCH OF AN UPPER TROUGH LIES FROM MADEIRA TOWARD THE CAPE VERDE ISLANDS. THIS TROUGH IS SUPPORTING A WEAK COLD FRONT WHICH STRETCHES FROM 32N13W TO 27N20W. UPPER LEVEL CONFLUENCE TO THE W OF THE TROUGH AXIS IS ENHANCING SUBSIDENCE FROM 24N-29N E OF 31W. OVER THE NEXT DAY OR TWO...GFS SHOWS THE SYNOPTIC SCALE MID-UPPER LEVEL PATTERN BECOMING MORE AMPLIFIED INTO A LARGE SCALE RIDGE/TROUGH. $$ CANGIALOSI