Tropical Storm ONE Advisory Fri Jul 24

MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/PROGNOSTIC REASONING FOR TYPHOON 01C (HALOLA) WARNING NR 53//
RMKS/
1. FOR METEOROLOGISTS.
2. 6 HOUR SUMMARY AND ANALYSIS.
   TYPHOON (TY) 01C (HALOLA), LOCATED APPROXIMATELY 413 NM EAST-
SOUTHEAST OF KADENA AB, HAS TRACKED WEST-NORTHWESTWARD AT 08 KNOTS
OVER THE PAST SIX HOURS. ANIMATED MULTISPECTRAL SATELLITE IMAGERY
DEPICTS A WEAKENING CONVECTIVE STRUCTURE, INDICATED BY WARMING CLOUD
TOPS IN ENHANCED INFRARED. THE SYSTEM CONTINUES TO MAINTAIN WELL
DEFINED SPIRAL BANDING, ALTHOUGH WATER VAPOR IMAGERY AND THE TOTAL
PRECIPITABLE WATER LOOP SHOWS DRY AIR WRAPPING IN TOWARDS THE CORE
OF THE CYCLONE. A 230626Z SSMIS 91 GHZ MICROWAVE IMAGE SHOWS A
BROADENING MICROWAVE EYE FEATURE WITH THE DEEPEST CORE CONVECTION
ALONG THE SOUTHEASTERN PERIPHERY. THE INITIAL POSITION IS BASED ON
THE AFOREMENTIONED IMAGERY AND SUPPORTED BY A PGTW AND RJTD
SATELLITE FIX. THE INITIAL INTENSITY IS HELD AT 90 KNOTS BASED ON A
CURRENT INTENSITY CONSENSUS OF T5.0 (90 KNOTS) FROM ALL AGENCIES.
UPPER LEVEL ANALYSIS SHOWS A DETERIORATING ENVIRONMENT WITH MODERATE
(15-20 KNOT) VERTICAL WIND SHEAR AND DRY AIR IMPACTING THE SYSTEM,
ALTHOUGH EXCELLENT EQUATORWARD OUTFLOW IS OFFSETTING SOME OF THE
EFFECTS. TY 01C CONTINUES TO TRACK ON A WESTWARD TRAJECTORY UNDER
THE STEERING INFLUENCE OF THE STRONG DEEP-LAYERED SUB-TROPICAL RIDGE
(STR) TO THE NORTH.
3. FORECAST REASONING.
   A. NO CHANGE TO THE FORECAST PHILOSOPHY SINCE THE PREVIOUS
PROGNOSTIC REASONING MESSAGE. THE WIND RADII HAVE BEEN INCREASED
BASED ON A 230118Z ASCAT PASS.
   B. TY HALOLA WILL CONTINUE TRACKING WESTWARD TO WEST-
NORTHWESTWARD UNDER THE STEERING INFLUENCE OF THE STR THROUGH TAU
36. TY 01C HAS THE POTENTIAL TO MAINTAIN INTENSITY OR EVEN SLIGHTLY
INTENSIFY OVER THE NEXT 12 TO 24 HOURS PRIOR TO ENVIRONMENTAL
CONDITIONS BECOMING INCREASINGLY UNFAVORABLE. AT THIS TIME VWS WILL
INCREASE TO ABOVE 25 KNOTS AND SEA SURFACE TEMPERATURES (SSTS) WILL
COOL SLIGHTLY. THESE FACTORS, IN ADDITION TO DECREASING DIFFLUENCE
ALOFT, WILL SERVE TO WEAKEN THE SYSTEM AS IT APPROACHES THE RYUKYU
ISLANDS. AFTER TAU 36, TY HALOLA WILL TURN POLEWARD AS IT ROUNDS THE
SOUTHWESTERN PERIPHERY OF THE STEERING STR AND BEGIN TO
ACCELERATE.
   C. IN THE EXTENDED TAUS, TY 01C WILL CONTINUE TO ACCELERATE
NORTHEASTWARD WHERE IT WILL ENCOUNTER HIGH (30-40 KNOT) VWS AND SSTS
BELOW 26 CELSIUS. THIS WILL CAUSE THE CYCLONE TO RAPIDLY WEAKEN,
LEADING TO ITS DISSIPATION BY THE END OF THE FORECAST PERIOD.
DYNAMIC MODEL GUIDANCE CONTINUES TO STRUGGLE WITH THE STRENGTH AND
POSITIONING OF THE STEERING STR, LEADING TO A WIDE SPREAD OF
SOLUTIONS BEYOND TAU 36. THIS CAUSES CONTINUED UNCERTAINTY IN THE
EXACT TIMING OF THE RE-CURVE AND LOW OVERALL CONFIDENCE IN THE JTWC
TRACK FORECAST.//
NNNN
NNNN