Subject: Pacific-NW: Subj/prognostic Reasoning For Typhoon 16w Warning Nr 19 Corrected//

From: SIU Weather Processor <[email-masked]>
Date: Tue, 26 Oct 2010 05:11:06 -0500

WDPN32 PGTW 260300 COR
MSGID/GENADMIN/NAVMARFCSTCEN PEARL HARBOR HI/JTWC//
SUBJ/PROGNOSTIC REASONING FOR TYPHOON 16W WARNING NR 19 CORRECTED//
RMKS/
1. FOR METEOROLOGISTS.
2. 12 HOUR SUMMARY AND ANALYSIS.
   A. TYPHOON (TY) 16W (CHABA), LOCATED APPROXIMATELY 430 NM SOUTH-
SOUTHEAST OF KADENA AIR BASE, JAPAN, HAS TRACKED NORTH-NORTHWESTWARD
AT 05 KNOTS DURING THE PAST SIX HOURS. ANIMATED MULTISPECTRAL
SATELLITE IMAGERY SHOWS DEEPENING CONVECTION OVER THE LOW LEVEL
CIRCULATION CENTER (LLCC). IMPROVED POLEWARD OUTFLOW DURING THE PAST
SIX HOURS IS RESPONSIBLE FOR MUCH OF THE INTENSIFICATION. A 252132Z
37 GHZ MICROWAVE PASS SHOWS A DEVELOPING MICROWAVE EYE AND
CONVECTIVE BANDING. INFRARED ANIMATION SHOWS A SHARP INCREASE IN
COLD TOPS OVER THE LLCC DURING THE PAST SIX HOURS. THE INITIAL
FORECAST INTENSITY IS BASED ON DVORAK ESTIMATES OF 65 KNOTS FROM
PGTW AND 77 KNOTS FROM RJTD. IN ADDITION TO IMPROVED POLEWARD
OUTFLOW, WELL-DEVELOPED EQUATORWARD OUTFLOW PERSISTS.
3. FORECAST REASONING.
   A. THERE ARE NO SIGNIFICANT CHANGES TO THE FORECAST PHILOSOPHY.
HOWEVER, TRACK SPEEDS AFTER TAU 72 HAVE BEEN INCREASED.
   B. TY CHABA WILL TRACK POLEWARD AROUND THE WESTERN PERIPHERY OF
THE DEEP LAYER SUBTROPICAL RIDGE THROUGH TAU 48. THE TY WILL
INTENSIFY AS A MID-LATITUDE TROUGH, CURRENTLY MOVING OVER THE SEA OF
JAPAN, ENHANCES POLEWARD OUTFLOW. GFDN, FORMERLY AN OUTLIER TO THE
WEST, HAS NOW JOINED THE PACK AND IS TRACKING THE SYSTEM TO THE EAST
OF OKINAWA.
   C. A COLD SURGE OVER THE WESTERN PACIFIC OCEAN HAS BROUGHT
MODIFIED CONTINENTAL POLAR AIR DEEP INTO THE THEATER. TY CHABA IS
EXPECTED TO RECURVE AND TRACK ALONG THE EAST COAST OF HONSHU, AFTER
TAU 72, WHILE UNDERGOING EXTRATROPICAL TRANSITION. DURING THE SAME
PERIOD THE TY WILL BE TRACKING OVER A REGION OF DECLINING OCEAN HEAT
CONTENT. NUMERICAL MODELS HAVE COME INTO BETTER AGREEMENT WITH THIS
SCENARIO, BUT NOGAPS AND EGRR APPEAR TO BE MISHANDLING THE TRACK
SOMEWHAT. THESE MODELS BOTH STEER THE TY OVER SHIKOKU AND INTO THE
SEA OF JAPAN, PUNCHING IT THROUGH A 100 KNOT POLAR FRONT JET. THE
FORECAST IS TO THE RIGHT AND FASTER THAN CONSENSUS, TO ACCOUNT FOR
THESE MODELS. CONSENSUS IS ALSO SLIGHTLY SLOWER, BUT VERY CLOSE TO
ECMWF. ECMWF HAS HANDLED THE TY'S TRACK BEST AMONG THE OTHER MODELS.
4. JUSTIFICATION FOR CORRECTION: CORRECTED FOR NUMEROUS SPELLING,
GRAMMATICAL AND SYNTAX ERRORS.//

+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
To unsubscribe from WX-TROPL send e-mail to [email-masked] with
"unsub wx-tropl" in the body of your message. For help with WX-TROPL
write to [email-masked]. For more information on tropical weather products, see the NHC Homepage at http://www.nhc.noaa.gov.