Subject: Pacific-NW: Subj/prognostic Reasoning For Tropical Storm 01w Warning Nr 04//

From: SIU Weather Processor <[email-masked]>
Date: Sun, 13 Jan 2008 20:46:10 -0600

WDPN31 PGTW 140300
MSGID/GENADMIN/NAVPACMETOCCEN PEARL HARBOR HI/JTWC//
SUBJ/PROGNOSTIC REASONING FOR TROPICAL STORM 01W WARNING NR 04//
RMKS/
1. FOR METEOROLOGISTS.
2. 12 HOUR SUMMARY AND ANALYSIS.
   A. TROPICAL STORM (TS) 01W (NONAME) HAS CONSOLIDATED IN THE
CENTRAL SOUTH CHINA SEA OVER THE PAST 12 HOURS. THE STORM TRACKED
WEST THAN WEST-SOUTHWESTWARD STEERED BY THE SUBTROPICAL RIDGE WHICH
BUILT IN TO THE NORTH AND WEST. STRATOCUMULUS CLOUDS ON METSAT
IMAGERY INDICATED COLD AIR HAD BEGUN TO WRAP INTO THE OUTER
WESTERN AND SOUTHEASTERN PERIPHERY OF THE STORM.
   B. THE WARNING POSITION IS BASED ON ANIMATED MULTISPECTRAL
IMAGERY AND A 140006Z SSMI MICROWAVE IMAGE. THE INTENSITY HAS
INCREASED SLIGHTLY FROM THE LAST WARNING AND THE INITIAL IN-
TENSITY IS BASED ON DVORAK ESTIMATES OF 2.5 FROM PGTW. UPPER
LEVEL ANALYSIS INDICATES THE SYSTEM REMAINS IN A REGION OF GOOD
UPPER LEVEL DIFFLUENCE AND LIGHT TO MODERATE WIND SHEAR. SYNOP-
TICALLY, A COLD, DRY AIR SURGE EXTENDED FURTHER SOUTH OVER THE
SOUTH CHINA SEA AND IS NOW WRAPPING IN TOWARD THE LOW LEVEL
CIRCULATION CENTER (LLCC).
 3. FORECAST REASONING
   A. FORECAST PHILOSOPHY HAS NOT DEVIATED SIGNIFICANTLY SINCE
THE LAST PROGNOSTIC REASON WITH THE EXCEPTION OF A SHIFT TO A
LATER DISSIPATION TIME.
   B. THE SUBTROPICAL RIDGE WILL CONTINUE TO STEER THE SYSTEM
SOUTHWESTWARD AS IT BUILDS TO THE NORTH AND WEST OF THE SYSTEM.
THE STORM HAS MOST LIKELY REACHED ITS MAXIMUM INTENSITY, AND WILL
WEAKEN DUE TO DRIER AIR ENTRAINMENT AND LOWER OCEAN HEAT CONTENT.
BY TAU 36, THE STORM IS EXPECTED TO HAVE COMPLETELY DISSIPATED.
THE CONSENSUS MODEL AIDS REMAIN IN GOOD AGREEMENT WITH THE CON-
TINUED EXCEPTION OF WBAR. WBAR FORECASTS A HIGHLY UNLIKELY SCENARIO
IN WHICH THE STORM WOULD TRACK DIRECTLY INTO THE COLD NORTHEASTERLY
FLOW.
FORECAST TEAM: ALPHA//

+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
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.