Tropical Storm ONE Advisory Sun Jul 19

MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/PROGNOSTIC REASONING FOR TROPICAL DEPRESSION 01C (HALOLA)
WARNING NR 38//
RMKS/
1. FOR METEOROLOGISTS.
2. 6 HOUR SUMMARY AND ANALYSIS.
   TROPICAL DEPRESSION (TD) 01C (HALOLA), LOCATED APPROXIMATELY 584
NM EAST-SOUTHEAST OF IWO TO, HAS TRACKED NORTHWESTWARD AT 11 KNOTS
OVER THE PAST SIX HOURS. ANIMATED ENHANCED INFRARED SATELLITE
IMAGERY DEPICTS PERSISTENT DEEP CENTRAL CONVECTION PARTIALLY
OBSCURING A BETTER DEFINED LOW LEVEL CIRCULATION CENTER (LLCC) WITH
SHALLOW CURVED BANDING WRAPPING INTO THE CENTER. A SERIES OF
MICROWAVE IMAGES, INCLUDING A 190800Z WINDSAT AND A 190850Z SSMIS,
SHOW WELL-DEFINED SHALLOW CURVED BANDING WRAPPING INTO THE LLCC WITH
THE DEEP CENTRAL CONVECTION SHEARED SLIGHTLY TO THE NORTHEAST DUE TO
LOW TO MODERATE (10-15 KNOT) SOUTHWESTERLY VERTICAL WIND SHEAR
(VWS). THE INITIAL POSITION IS BASED ON THE ABOVE IMAGERY AND
SUPPORTED BY A PGTW AND RJTD SATELLITE FIX WITH GOOD CONFIDENCE.
DVORAK INTENSITY ESTIMATES HAVE STARTED TO RISE DUE TO THE INCREASE
OF CENTRAL CONVECTION; HOWEVER, THE INITIAL INTENSITY IS HELD AT 30
KNOTS BASED ON THOSE ESTIMATES RANGING FROM 25 TO 30 KNOTS. ANIMATED
WATER VAPOR IMAGERY DEPICTS THE TUTT CELL MOVING TO THE NORTH
ALLOWING THE MOISTURE FIELD AND OUTFLOW ASSOCIATED WITH THE CYCLONE
TO EXPAND AND BECOME MORE SYMMETRIC. TD 01C IS TRACKING ALONG THE
SOUTHERN PERIPHERY OF THE DEEP-LAYERED STR.
3. FORECAST REASONING.
   A. THERE IS NO CHANGE TO THE FORECAST PHILOSOPHY SINCE THE
PREVIOUS PROGNOSTIC REASONING MESSAGE.
   B. TD HALOLA WILL TRACK WESTWARD TO WEST-NORTHWESTWARD UNDER THE
STEERING INFLUENCE OF THE DEEP-LAYERED STR THROUGH TAU 72. TD 01C
WILL SLOWLY INTENSIFY OVER THE NEXT 12 TO 24 HOURS AS IT CONTINUES
TO RE-ORGANIZE WITH INCREASED DIVERGENCE ALOFT AND LOW VWS. BEYOND
TAU 24, TD HALOLA IS FORECAST TO GAIN A STRONG EQUATORWARD OUTFLOW
CHANNEL AND ENCOUNTER REDUCED VWS, CONTINUING THE INTENSIFICATION.
DYNAMIC GUIDANCE REMAINS IN TIGHT AGREEMENT THROUGH TAU 48; HOWEVER,
THERE IS A CONTINUED SPREAD AT TAU 72 WHICH HAS VARIED FROM 100 TO
175NM.
   C. IN THE EXTENDED TAUS, EXPECT A MORE NORTHWESTWARD TRACK AS THE
SYSTEM APPROACHES THE WESTERN PERIPHERY OF THE STEERING STR. THIS
REGION WILL PROVIDE A POLEWARD OUTFLOW CHANNEL DOWNSTREAM FROM THE
STEERING STR; FURTHERING THE INTENSIFICATION TREND. TD HALOLA WILL
ENCOUNTER COOLER SEA SURFACE TEMPERATURES TOWARDS THE END OF THE
FORECAST PERIOD; HOWEVER, THE INCREASED POLEWARD OUTFLOW SHOULD
ALLOW THE CYCLONE TO MAINTAIN INTENSITY THROUGH THE END OF THE
FORECAST PERIOD. DYNAMIC MODEL GUIDANCE FANS OUT AFTER TAU 72, DUE
TO DIFFERENCES IN THE TIMING AND SPEED OF THE RE-CURVE. OVERALL
CONFIDENCE IN THE JTWC FORECAST TRACK IS LOW DUE TO THE
AFOREMENTIONED UNCERTAINTY IN THE RE-CURVE PHASE. IN ADDITION, LOW
CONFIDENCE REMAINS IN THE NEAR TERM INTENSITY FORECAST AS TD HALOLA
ATTEMPTS TO RE-ORGANIZE AFTER THE COMPLEX INTERACTION WITH THE TUTT
CELL.//
NNNN
NNNN