ZCZC MIATCDEP3 ALL TTAA00 KNHC DDHHMM HURRICANE BLAS DISCUSSION NUMBER 7 NATIONAL WEATHER SERVICE MIAMI FL 8 PM PDT TUE JUN 23 1998 BLAS HAS INTENSIFIED CONSIDERABLY THIS EVENING. AN EYE HAS RECENTLY APPEARED IN SATELLITE IMAGERY AND THE INITIAL INTENSITY IS INCREASED TO 90 KNOTS IN AGREEMENT WITH THE LATEST DVORAK ESTIMATE FROM TAFB. WITH THE OUTFLOW AROUND BLAS WELL-ESTABLISHED AND WARM SST/S... CONTINUED STRENGTHENING IS FORECAST FOR AT LEAST ANOTHER 24 HOURS. WEAKENING IS EXPECTED AS IT ENCOUNTERS COOLER WATERS ONLY TOWARD THE END OF THE FORECAST PERIOD. THE SYSTEM REMAINS ON A WEST-NORTHWEST HEADING WITH THE INITIAL MOTION ESTIMATE OF 290/14 KNOTS. THE MID-TO UPPER LEVEL TROPOSPHERIC ANTICYCLONE POSITIONED OVER NORTHWESTERN MEXICO..PER LATEST WATER VAPOR IMAGERY... SHOULD KEEP BLAS ON THIS GENERAL COURSE THROUGH 72 HOURS. THIS IS SUPPORTED BY THE GLOBAL SPECTRAL MODEL 500 MB ENSEMBLE DATA. THE SHORT-WAVE TROUGH CURRENTLY OVER THE WESTERN U.S. COULD WEAKEN THE RIDGE ENOUGH TO SLOW THE FORWARD SPEED LATER IN THE FORECAST PERIOD. THE OFFICIAL FORECAST IS IN CLOSEST AGREEMENT WITH THE BAM GUIDANCE. GUINEY/MAYFIELD FORECAST POSITIONS AND MAX WINDS INITIAL 24/0300Z 13.1N 103.4W 90 KTS 12HR VT 24/1200Z 13.8N 105.5W 100 KTS 24HR VT 25/0000Z 14.8N 107.9W 115 KTS 36HR VT 25/1200Z 15.6N 110.1W 115 KTS 48HR VT 26/0000Z 16.5N 112.0W 100 KTS 72HR VT 27/0000Z 17.5N 115.5W 80 KTS NNNN