000 WTPZ42 KNHC 301443 TCDEP2 TROPICAL DEPRESSION SEVEN-E DISCUSSION NUMBER 1 NWS NATIONAL HURRICANE CENTER MIAMI FL EP072013 800 AM PDT TUE JUL 30 2013 INFRARED AND MICROWAVE SATELLITE IMAGERY INDICATE THAT THE SMALL AREA OF LOW PRESSURE EMBEDDED WITHIN THE INTERTROPICAL CONVERGENCE ZONE ABOUT 700 N MI SOUTH-SOUTHWEST OF THE SOUTHERN TIP OF THE BAJA CALIFORNIA PENINSULA QUICKLY BECAME MORE ORGANIZED OVERNIGHT...AND IT APPEARS THAT IT HAS BECOME A TROPICAL DEPRESSION. THE INITIAL INTENSITY IS BEING SET AT 25 KT BASED ON DVORAK ESTIMATES OF T2.0 FROM TAFB AND T1.0 FROM SAB. THE DEPRESSION IS BEING STEERED WEST-NORTHWESTWARD BY AN ANOMALOUSLY STRONG MID-LEVEL HIGH PRESSURE SYSTEM LOCATED OVER NORTHERN MEXICO...GIVING THE CYCLONE AN INITIAL MOTION OF 285/14 KT. THE HIGH IS EXPECTED TO STAY RATHER STRONG FOR ANOTHER DAY OR TWO AND THEN WEAKEN BEGINNING IN 72 HOURS. THE DEPRESSION IS ALSO FORECAST TO REACH THE WESTERN EDGE OF THE RIDGE IN ABOUT 72 HOURS...WHICH SHOULD CAUSE IT TO DECELERATE BUT MAINTAIN A WESTWARD TO WEST- NORTHWESTWARD TRAJECTORY BETWEEN DAYS 3 AND 5. THE TRACK GUIDANCE IS IN DECENT AGREEMENT ON THIS SCENARIO...ALTHOUGH THE ECMWF MODEL IS A LITTLE FASTER AND FARTHER SOUTH THAN THE OTHER DYNAMICAL MODELS DURING THE FIRST 4 DAYS OF THE FORECAST PERIOD. SINCE CYCLONES USUALLY HAVE A DIFFICULT TIME ESCAPING FROM THE ITCZ...THE NHC OFFICIAL FORECAST LEANS TOWARD THE ECMWF AND IS JUST A LITTLE SOUTHWEST OF THE MODEL CONSENSUS TVCE FOR MOST FORECAST TIME PERIODS. EXCEPT FOR THE FACT THAT THE DEPRESSION IS STILL EMBEDDED IN THE ITCZ...WHICH OFTEN INHIBITS SIGNIFICANT STRENGTHENING...THE ENVIRONMENT APPEARS CONDUCIVE FOR INTENSIFICATION. DEEP-LAYER SHEAR IS LIGHT...SEA SURFACE TEMPERATURES ARE ALMOST 29C...AND THERE IS PLENTY OF AVAILABLE MOISTURE. THE INTENSITY MODELS ALL INDICATE STRENGTHENING...AND IN FACT...THE SHIPS RAPID INTENSIFICATION INDEX IS INDICATING A 1 IN 3 CHANCE OF A 30-KT INCREASE IN WINDS DURING THE NEXT 24 HOURS. THE NHC INTENSITY FORECAST INDICATES STEADY STRENGTHENING...WITH THE SYSTEM HAVING THE POTENTIAL TO BECOME A HURRICANE IN A FEW DAYS. FORECAST POSITIONS AND MAX WINDS INIT 30/1500Z 12.2N 114.9W 25 KT 30 MPH 12H 31/0000Z 12.9N 116.7W 35 KT 40 MPH 24H 31/1200Z 13.6N 119.0W 45 KT 50 MPH 36H 01/0000Z 14.2N 121.2W 55 KT 65 MPH 48H 01/1200Z 14.8N 123.3W 60 KT 70 MPH 72H 02/1200Z 15.7N 127.0W 65 KT 75 MPH 96H 03/1200Z 16.5N 130.5W 55 KT 65 MPH 120H 04/1200Z 17.0N 133.5W 45 KT 50 MPH $$ FORECASTER BERG