je.st
news
Tropical Storm ALVIN Forecast Discussion Number 4
2013-05-16 10:56:51| National Hurricane Center (East Pacific)
Issued at 200 AM PDT THU MAY 16 2013 000 WTPZ41 KNHC 160856 TCDEP1 TROPICAL STORM ALVIN DISCUSSION NUMBER 4 NWS NATIONAL HURRICANE CENTER MIAMI FL EP012013 200 AM PDT THU MAY 16 2013 ALVIN CONTINUES TO SLOWLY STRENGTHEN WITH SATELLITE IMAGES SHOWING VERY DEEP CONVECTION RESEMBLING A CENTRAL DENSE OVERCAST. MICROWAVE PASSES...HOWEVER...SHOW A LESS ORGANIZED SYSTEM THAN A QUICK GLANCE WOULD SUGGEST...WITH THE LOW-LEVEL CENTER DISPLACED A FAIR DISTANCE WEST OF THE STRONGEST BURST. ASCAT AND SATELLITE ESTIMATES SUGGEST AN INTENSITY OF ABOUT 45 KT...SO THAT WILL BE THE INITIAL WIND SPEED. CURRENT WATER VAPOR IMAGES SHOW A LOT OF UPPER-LEVEL WESTERLY WINDS HEADED TOWARD THE CYCLONE...WITH SOME EVIDENCE OF THE FLOW ALREADY IMPINGING ON THE CENTER. THE FUTURE STRENGTH OF THE CYCLONE IS NOT AN EASY FORECAST THIS MORNING WITH CONSIDERABLY MORE SHEAR IN MOST OF THE MODEL FIELDS THAN YESTERDAY. ALTHOUGH ALL OF THE GUIDANCE CONTINUE TO SHOW SOME INTENSIFICATION...ONLY THE GFDL MODEL REALLY SHOWS ALVIN BECOMING ANY MORE THAN A LOW-END CATEGORY ONE HURRICANE. THE NEW NHC FORECAST IS ABOUT THE SAME AS THE PREVIOUS ONE FOR THE FIRST 24H...THEN IS REDUCED FOR THE REST OF THE FORECAST PERIOD TO ACCOUNT FOR THE LATEST MODEL CONSENSUS GUIDANCE. WEAKENING SHOULD COMMENCE IN ABOUT 3 DAYS DUE TO INCREASING WESTERLY SHEAR AND GRADUALLY DECREASING SSTS. A BEVY OF ASCAT AND OTHER MICROWAVE DATA SHOW THAT ALVIN IS MOVING A BIT SLOWER...290/9. THIS GENERAL MOTION SEEMS PROBABLE DURING THE NEXT COUPLE OF DAYS WHILE THE CYCLONE REMAINS SOUTH OF A MID-LEVEL RIDGE OVER MEXICO. AFTER THAT TIME...GLOBAL MODELS ARE GENERALLY SHOWING LESS OF AN INTERACTION BETWEEN A TROUGH OVER THE SOUTHWESTERN UNITED STATES AND ALVIN...WHICH RESULTS IN LESS OF A TURN TO THE NORTHWEST IN THE LONGER RANGE. THE OFFICIAL FORECAST HAS BEEN SHIFTED TO THE LEFT OF THE PREVIOUS ONE...FOLLOWING THE TREND OF THE GUIDANCE...BUT IS GENERALLY TO THE RIGHT OF THE MODEL CONSENSUS AFTER 24H. FORECAST POSITIONS AND MAX WINDS INIT 16/0900Z 9.1N 106.9W 45 KT 50 MPH 12H 16/1800Z 9.5N 108.2W 50 KT 60 MPH 24H 17/0600Z 10.2N 109.8W 60 KT 70 MPH 36H 17/1800Z 11.0N 111.5W 65 KT 75 MPH 48H 18/0600Z 11.6N 112.8W 65 KT 75 MPH 72H 19/0600Z 12.8N 115.2W 60 KT 70 MPH 96H 20/0600Z 14.0N 117.0W 40 KT 45 MPH 120H 21/0600Z 14.5N 118.5W 25 KT 30 MPH $$ FORECASTER BLAKE
Tags: number
discussion
storm
tropical
Category:Transportation and Logistics
Latest from this category |
All news |
||||||||||||||||||
|
|||||||||||||||||||