Action in the W. Pacific

[James]

Well, no sooner had Cyclone Arola dissipated in the Indian Ocean, something began to form in the W. Pacific. NRL has issued a Tropical Cyclone Formation Alert for Invest 93W. Just thought I'd mention it since it is the only tropical cyclone anywhere on Earth (even if it is in the formative stages).

http://www.nrlmry.navy.mil/tc-bin/tc_home2.cgi?YEAR=2004&MO=NOV&BASIN=WPAC&STORM_NAME=93W.INVEST&PROD=latest1km&PHOT=yes&DISPLAY=Latest&ARCHIVE=active&TYPE=ssmi&SIZE=thumb&NAV=tc&CURRENT=20041113.2001.goes9.x.ir1km_bw.93WINVEST.20kts-1004mb-108N-1343E.jpg&DIR=/data/www/tropical_cyclones/tc04/WPAC/93W.INVEST/ssmi/latest1km&STYLE=tables&CURRENT_ATCF=wp932004.04111306.gif&ATCF_NAME=wp932004&DIR=/data/www/tropical_cyclones/tc04/WPAC/93W.INVEST/ssmi/latest1km

[cycloneye]

132000
MSGID/GENADMIN/NAVPACMETOCCEN PEARL HARBOR HI/JTWC//
SUBJ/TROPICAL CYCLONE FORMATION ALERT 132000Z NOV 04//
RMKS/
1. FORMATION OF A SIGNIFICANT TROPICAL CYCLONE IS POSSIBLE WITHIN 200
NM EITHER SIDE OF A LINE FROM 10.7N8 135.0E9 TO 11.8N0 128.0E1 WITHIN
THE NEXT 12 TO 24 HOURS. AVAILABLE DATA DOES NOT JUSTIFY ISSUANCE OF
NUMBERED TROPICAL CYCLONE WARNINGS AT THIS TIME. WINDS IN THE AREA
ARE ESTIMATED TO BE 20 TO 25 KNOTS. METSAT IMAGERY AT 131730Z5
INDICATES THAT A CIRCULATION CENTER IS LOCATED NEAR 10.8N9 134.3E1.
THE SYSTEM IS MOVING WESTWARD AT 07 KNOTS.
2. REMARKS: AN AREA OF CONVECTION NEAR 10.8N9 134.3E1, APPROXIMATELY
205 NM NORTH OF PALAU, HAS PERSISTED OVER THE PAST 12 HOURS. RECENT
ANIMATED ENHANCED INFRARED SATELLITE IMAGERY REVEALS DEEP CONVECTION
CONTINUES TO CONSOLIDATE AROUND THE LOW-LEVEL CIRCULATION
CENTER (LLCC), AND ANIMATED ENHANCED WATER VAPOR IMAGERY SHOWS AN
INCREASE IN OVERALL RADIAL OUTFLOW. THE STRONGEST CONVECTION HAS
REMAINED IN THE SOUTHWEST QUADRANT AND IS LEADING THE LLCC. UPPER
LEVEL ANALYSIS INDICATES THE SYSTEM IS IN AN ENVIRONMENT OF LOW TO
MODERATE VERTICAL WIND SHEAR, AND STREAMLINE ANALYSIS REVEALS A POINT
SOURCE WHICH IS PROMOTING FAVORABLE UPPER LEVEL DIVERGENCE. MAXIMUM
SURFACE WINDS ARE ESTIMATED AT 20 TO 25 KNOTS. MINIMUM SEA LEVEL
PRESSURE IS ESTIMATED TO BE NEAR 1004 MB. DUE TO THE RAPID INCREASE
IN DEEP CONVECTION AND RADIAL OUTFLOW, THE POTENTIAL FOR THE DEVELOP-
MENT OF A SIGNIFICANT TROPICAL CYCLONE WITHIN THE NEXT 24 HOURS IS
GOOD.
3. THIS ALERT WILL BE REISSUED, UPGRADED TO WARNING OR CANCELLED BY
142000Z7.//

Looks like the next cyclone in the tropics.

[James]

Hey, I was just wondering, when they say 'significant' , how strong do they mean it could get? Do they mean it could get to a Tropical Storm, or a full blown Typhoon?

As a point of interest, if it becomes named it will be known as 'Muifa'.

[P.K.]

Don't these tropical cyclone formation alerts always say they could be significant? I'd have thought it just means it could reach or exceed TS status, but then I'm not sure.

[James]

Well, they do usually seem to say 'significant', but I was just wondering what sort of strength they actually meant by that. I suppose that isn't of huge importance, because we've seen many times weak storms have terrible effects.

[P.K.]

The large amount of rain produced by TDs can be very bad some times.

[James]

I agree. There are plenty of examples, I'm sure.

[cycloneye]

I think by significant they mean Tropical Depression.

[P.K.]

Thanks, I meant TD when I typed TS a few posts ago.

[Aslkahuna]

It is considered a significant Tropical Cyclone if there are advisories being issued on it. That would mean anything of Tropical Depression intensity or higher. The system is at 134E, it could become a minimal typhoon before reaching the Philippines or it could track through the Visayas as a TD/TS and enter the lower South China Sea and become a Typhoon as it passes south of Viet Nam. Or it could turn north and bomb out as it tracks east of the Philippines-those are the three main possible scenarios at this point.

Steve

[James]

Thanks for clarifying that guys! Stupid question, I know, but I was just curious.