000 AXNT20 KNHC 221124 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 705 AM EST THU FEB 22 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 7N12W 2N23W 1N34W EQ40W CROSSING THE EQUATOR NEAR 46W AND INTO NE BRAZIL. CLUSTERS OF SCATTERED MODERATE CONVECTION ARE WITHIN 90 NM EITHER SIDE OF THE AXIS BETWEEN 18W-21W AND FROM THE EQ TO 4N BETWEEN 48W-51W. ...DISCUSSION... GULF OF MEXICO... WEAK HIGH PRES RIDGING IS THE OVERALL THEME ACROSS THE W ATLC AND GULF WITH A 1022 MB HIGH CENTERED NEAR 29N91W. THERE ARE TWO VERY WEAK SFC TROUGHS ANALYZED IN THE REGION. ONE OF THESE EXTENDS FROM THE ATLC ACROSS S/CENTRAL FL TO 26N86W. THE OTHER IS ALONG THE MEXICAN GULF COAST FROM 18N-23N. NEITHER OF THESE LOW LEVEL TROUGHS ARE PRODUCING ANY NOTABLE WEATHER. ALOFT...THE FLOW IS RATHER ZONAL TO WNW...SANDWICHED BETWEEN A SPRAWLING RIDGE CENTERED OVER S MEXICO AND TROUGHING ALONG AND OFFSHORE OF THE U.S. EAST COAST. WV IMAGES SHOW A GOOD AMOUNT OF DRY AIR ACROSS THE ENTIRE AREA...ESPECIALLY N OF 27N AND S OF 22N CLOSER TO THE UPPER CONFLUENT ZONES. ESSENTIALLY THIS PATTERN...BOTH THE SFC AND ALOFT...IS LEADING TO FAIR AND MILD WEATHER ACROSS THE REGION WITH LIGHT WINDS. OVER THE NEXT COUPLE OF DAYS...THE SFC PATTERN IS EXPECTED TO TIGHTEN UP AS STRONG CANADIAN HIGH PRES RIDGING EXTENDS WELL S INTO THE AREA. AS THIS HIGH SLIDES E...SLY RETURN FLOW IS EXPECTED TO INCREASE IN THE W GULF BEGINNING LATE FRI IN RESPONSE TO THE NEXT COLD FRONT FORECAST TO PUSH OFF THE TX COAST ON SAT. CARIBBEAN SEA... A RELATIVELY TIGHT PRES GRAD...BETWEEN HIGH PRES LOCATED IN THE SW ATLC AND LOW PRES OVER S AMERICA...IS PRODUCING MODERATE TO STRONG TRADES ACROSS THE CENTRAL CARIB. TYPICAL PATCHES OF LOW LEVEL MOISTURE WITH EMBEDDED SHOWERS DRIVEN BY THE TRADES ARE AFFECTING THE AREA...PARTICULARLY THE E CARIBBEAN AND OVER THE ISLAND OF HISPANIOLA. THE MID AND UPPER LEVEL PATTERN IS DOMINATED BY A STRONG RIDGE CENTERED OVER S MEXICO. NEARLY ALL OF THE REGION LIES ON THE E SIDE...DOWNWARD BRANCH...OF THE RIDGE ENHANCING AN ABUNDANCE OF EXTREMELY DRY/STABLE AIR. THIS STRONG CAP IS SUPPLYING THE AREA WITH FAIR WEATHER...PREVENTING THE LOW LEVEL MOISTURE PATCHES OF ACQUIRING MUCH DEPTH. OVER THE NEXT COUPLE OF DAYS...NWP MODELS SHOW LITTLE CHANGE IN THE OVERALL PATTERN SO SIMILAR TRADES/WX CONDITIONS ARE ANTICIPATED. ATLANTIC OCEAN... THE SFC PATTERN IS DOMINATED BY A LARGE FLAT RIDGE STRETCHED ACROSS THE ENTIRE BASIN. THERE ARE TWO EMBEDDED HIGH CENTERS...THE STRONGER IS 1025 MB LOCATED 250 NM OR SO W OF THE CANARY ISLANDS. THE OTHER IS 1020 MB LOCATED BETWEEN BERMUDA AND HISPANIOLA NEAR 25N67W. THIS STRETCHED RIDGE IS FURTHER S THAN NORMAL AND IS PRODUCING FAIR WEATHER ACROSS THE MAJORITY OF THE DISCUSSION AREA. THE MID AND UPPER LEVEL PATTERN IS A LITTLE MORE COMPLEX. STRONG ZONAL FLOW ALOFT COVERS MOST OF THE AREA W OF 50W. AN UPPER DIFFLUENCE ZONE IS GENERATING A SWATH OF MOISTURE CONFINED N OF 28N BETWEEN 42W-73W. THIS SWATH IS QUICKLY PUSHING E BEING REPLACED BY MUCH DRIER AIR ALOFT. AN UPPER LEVEL TROUGH DIPS TO A BASE NEAR 31N41W HELPING TO FURTHER LIFT THE MOISTURE MOSTLY N OF 32N BETWEEN 30W-40W. THIS UPPER TROUGH SUPPORTS A WEAK STATIONARY OR SLOW MOVING WARM FRONT ALONG 30N32W 32N40W 26N51W 21N62W. THE FRONT IS SLOWLY BECOMING DIFFUSE ONLY DEFINED BY BROKEN MULTILAYERED CLOUDS AND A WIND SHIFT. IN THE TROPICAL ATLC...A WEAK UPPER TROUGH HAS DEVELOPED ROUGHLY ALONG 20N48W 10N58W. E OF THE TROUGH AXIS...SWLY FLOW IS ADVECTING SOME HIGH LEVEL MOISTURE NWD BETWEEN 41W-47W S OF 19N. THIS MOISTURE THEN GETS SUPPRESSED S BY ANOTHER WEAK TROUGH ALONG 32W S OF 18N. IN THE SUBTROPICAL E ATLC...A STRONG UPPER LEVEL RIDGE IS IN CONTROL KEEPING CONDITIONS TRANQUIL. $$ CANGIALOSI