je.st
news
Tropical Storm ALVIN Forecast Discussion Number 2
2013-05-15 22:36:44| National Hurricane Center (East Pacific)
Issued at 200 PM PDT WED MAY 15 2013 000 WTPZ41 KNHC 152036 TCDEP1 TROPICAL STORM ALVIN DISCUSSION NUMBER 2 NWS NATIONAL HURRICANE CENTER MIAMI FL EP012013 200 PM PDT WED MAY 15 2013 ASCAT DATA FROM AROUND 1612 UTC SHOWED THAT THE DEPRESSION HAD WINDS VERY NEAR THE THRESHOLD FOR A TROPICAL STORM. THE CLOUD PATTERN IN VISIBLE IMAGERY HAS BECOME MORE ORGANIZED SINCE THE TIME OF THAT PASS...AND IT IS LIKELY THAT THE SYSTEM HAS BECOME A TROPICAL STORM. THE INTENSITY IS BEING SET AT 35 KT. THE ASCAT PASS ALSO HELPED TO BETTER LOCATE THE LOW-LEVEL CENTER...AND THE INITIAL MOTION ESTIMATE IS NOW 290 DEGREES AT 11 KT. ALVIN IS ON THE SOUTHWESTERN PERIPHERY OF A MID-LEVEL RIDGE THAT EXTENDS SOUTHWESTWARD FROM MAINLAND MEXICO OVER THE PACIFIC...AND THIS FEATURE SHOULD CONTINUE TO STEER THE STORM WEST-NORTHWESTWARD FOR THE NEXT FEW DAYS. A MID-LEVEL TROUGH IS FORECAST TO AMPLIFY NEAR CALIFORNIA COAST IN 2 TO 3 DAYS...CREATING A WEAKNESS IN THE RIDGE. THERE IS A SIGNIFICANT SPLIT IN THE MODEL GUIDANCE WITH THE STRONGER GFS AND GFDL SHOWING A TURN TOWARD THE NORTH AND THE WEAKER ECMWF AND UKMET MODELS SHOWING A CONTINUED WESTWARD MOTION BY DAY 5. THE OFFICIAL FORECAST SOMEWHAT SPLITS THE DIFFERENCE BUT DOES FAVOR THE SCENARIO OF A STRONGER NORTHWESTWARD-TURNING STORM. MOST OF THE INTENSITY GUIDANCE SUPPORTS ALVIN REACHING HURRICANE STRENGTH IN A FEW DAYS. THE DYNAMICAL GFDL AND HWRF MODELS ARE THE MOST AGGRESSIVE...BUT EVEN THE SHIPS MODEL SHOWS ALVIN GETTING STRONGER THAN WE INDICATED IN THE PREVIOUS OFFICIAL FORECAST. ALVIN IS ABOUT TO MOVE OVER A WARM POOL OF WATER WITH SEA SURFACE TEMPERATURES AROUND 30.5C...AND VERTICAL SHEAR SHOULD BE MINIMAL FOR AT LEAST THE NEXT 3 DAYS. THE NHC INTENSITY FORECAST CONTINUES TO SHOW A STEADY INTENSIFICATION AND HAS BEEN BUMPED UP SLIGHTLY FROM THE PREVIOUS FORECAST THROUGH DAY 3. FASTER STRENGTHENING IS POSSIBLE...AND THE RAPID INTENSIFICATION INDEX NOW SHOWS A 1 IN 3 CHANCE OF A 30-KT INCREASE IN WINDS OVER THE NEXT 24 HOURS. WEAKENING SHOULD BE UNDERWAY IN 4 TO 5 DAYS MAINLY DUE TO STRONGER VERTICAL WIND SHEAR. FORECAST POSITIONS AND MAX WINDS INIT 15/2100Z 8.7N 105.1W 35 KT 40 MPH 12H 16/0600Z 9.3N 106.5W 40 KT 45 MPH 24H 16/1800Z 10.0N 108.2W 50 KT 60 MPH 36H 17/0600Z 10.6N 109.8W 60 KT 70 MPH 48H 17/1800Z 11.1N 111.4W 70 KT 80 MPH 72H 18/1800Z 12.5N 114.0W 75 KT 85 MPH 96H 19/1800Z 14.0N 116.0W 60 KT 70 MPH 120H 20/1800Z 15.5N 117.5W 40 KT 45 MPH $$ FORECASTER BERG
Tags: number
discussion
storm
tropical
Category:Transportation and Logistics
Latest from this category |
All news |
||||||||||||||||||
|
|||||||||||||||||||