Tropical Depression NINE ZCZC MIATCDAT4 ALL TTAA00 KNHC DDHHMM TROPICAL DEPRESSION NINE DISCUSSION NUMBER 1 NWS NATIONAL HURRICANE CENTER MIAMI FL AL092012 500 AM AST TUE AUG 21 2012 THE LARGE LOW PRESSURE SYSTEM THAT HAS BEEN TRAVERSING THE CENTRAL TROPICAL ATLANTIC FOR THE PAST FEW DAYS HAS ACQUIRED ENOUGH ORGANIZED DEEP CONVECTION NEAR THE CENTER TO BE CLASSIFIED AS A TROPICAL DEPRESSION. THE INITIAL INTENSITY OF 30 KT IS BASED ON A SATELLITE INTENSITY ESTIMATE OF T2.0/30 KT FROM TAFB AND T1.5/25 KT FROM SAB. SINCE THE 0600 UTC SATELLITE CLASSIFICATIONS... CONVECTION HAS CONTINUED TO INCREASE WITH SOME CLOUD TOP TEMPERATURES COLDER THAN -80C NOTED JUST SOUTHWEST OF THE LOW-LEVEL CENTER. THE INITIAL MOTION ESTIMATE IS 270/17 KT. THE DEPRESSION IS LOCATED SOUTH OF A DEEP-LAYER SUBTROPICAL RIDGE THAT IS FORECAST TO REMAIN INTACT FOR THE NEXT FOUR DAYS...WHICH SHOULD KEEP THE CYCLONE MOVING IN A WESTWARD TO WEST-NORTHWESTWARD DIRECTION THROUGH 96 HOURS. BY DAY 5...HOWEVER...THE GLOBAL MODELS ARE FORECASTING A SHORTWAVE TROUGH TO DIG SOUTHWARD OVER THE SOUTHEASTERN U.S. AND THE GULF OF MEXICO...WHICH IS EXPECTED TO WEAKEN THE RIDGE ACROSS FLORIDA AND THE BAHAMAS. THIS SHOULD ALLOW THE CYCLONE TO TURN NORTHWESTWARD AND SLOW DOWN ACROSS THE NORTH-CENTRAL CARIBBEAN SEA. THE OFFICIAL FORECAST TRACK IS CLOSE TO THE MULTI-MODEL CONSENSUS TVCA...WHICH IS A COMPROMISE OF THE FASTER GFS MODEL AND SLOWER ECMWF MODEL. OTHER THAN SOME MODEST NORTHEASTERLY VERTICAL WIND SHEAR FOR THE NEXT 24 HOURS OR SO...ENVIRONMENTAL CONDITIONS ARE EXPECTED TO BE QUITE FAVORABLE FOR INTENSIFICATION TO OCCUR. DURING DAYS 2-3...THE VERTICAL SHEAR IS FORECAST TO BE THE WEAKEST AND WATER TEMPERATURES THE WARMEST...AND THAT IS WHEN THE MOST SIGNIFICANT STRENGTHENING SHOULD OCCUR. AT DAYS 4 AND 5...POSSIBLE INTERACTION WITH LAND MASSES OF HAITI AND CUBA...RESPECTIVELY...IS THE PRIMARY REASON FOR THE LEVELING OFF IN THE INTENSITY. THE OFFICIAL INTENSITY FORECAST CLOSELY FOLLOWS THE TREND OF...BUT IS LOWER THAN...THE SHIPS AND LGEM INTENSITY MODELS...ESPECIALLY AT DAYS 3 AND 4. AN AIR FORCE RESERVE RECONNAISSANCE AIRCRAFT WILL INVESTIGATE THE CYCLONE THIS AFTERNOON. FORECAST POSITIONS AND MAX WINDS INIT 21/0900Z 15.2N 51.2W 30 KT 35 MPH 12H 21/1800Z 15.3N 53.8W 35 KT 40 MPH 24H 22/0600Z 15.7N 57.2W 40 KT 45 MPH 36H 22/1800Z 16.0N 60.5W 50 KT 60 MPH 48H 23/0600Z 16.3N 63.6W 65 KT 75 MPH 72H 24/0600Z 16.9N 69.3W 80 KT 90 MPH 96H 25/0600Z 18.0N 74.0W 95 KT 110 MPH 120H 26/0600Z 20.0N 77.3W 95 KT 110 MPH $$ FORECASTER STEWART NNNN
Potężny Huragan Isaac uderzył w USA. Nawiedził miasto Nowy Orlean. Już co najmniej 36 osób nie żyje. W niedzielę 26 sierpnia po południu huragan uderzył we Florydę. Potem skręcił na zachód i przeszedł nad Nowym Orleanem. Miasto zostało zalane, a w okolicy ogłoszono stan klęski powodziowej. Ludzie zabili deskami swoje domy, a wielu opuściło miasto. Kiedy huragan uderzył, jego siła była mniejsza niż zapowiadano, jednak nadal była duża.