WPAC: Tropical Depression LEKIMA

Coredesat · #1 Postby **Coredesat** » Wed Sep 26, 2007 8:11 pm

Looking pretty decent:

B. TROPICAL DISTURBANCE SUMMARY:
(1) THE AREA OF CONVECTION PREVIOUSLY LOCATED NEAR 10.3N
141.2E, IS NOW LOCATED NEAR 14.4N 137.3E, APPROXIMATELY 415 NM WEST
OF GUAM. RECENT ANIMATED ENHANCED INFRARED SATELLITE IMAGERY
INDICATES FORMATIVE CONVECTIVE BANDING ALONG THE WESTERN AND EASTERN
PERIPHERY OF A BROAD AREA OF CYCLONIC TURNING. THERE IS STILL NO
DISCERNABLE LOW LEVEL CIRCULATION CENTER. UPPER LEVEL ANALYSIS
INDICATES THE DISTURBANCE IS IN A REGION OF FAVORABLE DIVERGENCE
ALOFT ON THE SOUTHWESTERN PERIPHERY OF A 200 MB ANTICYCLONE CENTERED
OVER THE MARIANAS. AS THIS ANTICYCLONE HAS MIGRATED WESTWARD OVER
THE PAST 12 HOURS, VERTICAL WIND SHEAR HAS DECREASED OVER THE CENTER
OF THE DISTURBANCE ALLOWING FOR CONVECTIVE DEVELOPMENT TO INCREASE.
MAXIMUM SUSTAINED SURFACE WINDS ARE ESTIMATED AT 15 TO 20 KNOTS.
MINIMUM SEA LEVEL PRESSURE IS ESTIMATED TO BE NEAR 1006 MB. THE
POTENTIAL FOR THE DEVELOPMENT OF A SIGNIFICANT TROPICAL CYCLONE
WITHIN THE NEXT 24 HOURS IS UPGRADED TO FAIR.

#2 Postby **RL3AO** » Thu Sep 27, 2007 7:40 pm

WTPN21 PGTW 271600 COR
MSGID/GENADMIN/NAVPACMETOCCEN PEARL HARBOR HI/JTWC//
SUBJ/TROPICAL CYCLONE FORMATION ALERT CORRECTED//
RMKS/
1. FORMATION OF A SIGNIFICANT TROPICAL CYCLONE IS POSSIBLE WITHIN
200 NM EITHER SIDE OF A LINE FROM 14.3N 131.5E TO 16.9N 121.8E
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 18 TO 22 KNOTS. METSAT IM-
AGERY AT 271200Z INDICATES THAT A CIRCULATION CENTER IS LOCATED
NEAR 14.3N 131.4E. THE SYSTEM IS MOVING WESTWARD AT 21 KNOTS.
2. REMARKS: THE AREA OF CONVECTION PREVIOUSLY LOCATED NEAR 14.0N
136.3E, IS NOW LOCATED NEAR 14.3N 131.4E, APPROXIMATELY 610 NM
EAST OF MANILA, PHILIPPINES. RECENT ANIMATED MULTISPECTRAL AND
INFRARED SATELLITE IMAGERY DEPICTS IMPROVED CONVECTIVE BANDING
INTO A DEVELOPING LOW LEVEL CIRCULATION CENTER (LLCC). A 271122Z
SSMIS MICROWAVE SATELLITE IMAGE INDICATES CONVECTIVE BANDS WRAP-
PING INTO THE LLCC FROM THE NORTH AND WEST WITH MINIMAL BANDING
FROM THE EAST. UPPER LEVEL ANALYSIS INDICATES THAT THE DISTURBANCE
CONTINUES TO BE IN A REGION OF FAVORABLE DIVERGENCE ALOFT ON THE
SOUTHWESTERN PERIPHERY OF A 200 MB ANTICYCLONE CENTERED OVER THE
MARIANA ISLANDS. VERTICAL WIND SHEAR HAS DECREASED OVER THE CENTER
OF THE DISTURBANCE ALLOWING FOR CONVECTIVE DEVELOPMENT TO INCREASE.
MAXIMUM SUSTAINED SURFACE WINDS ARE ESTIMATED AT 18 TO 22 KNOTS.
MINIMUM SEA LEVEL PRESSURE IS ESTIMATED TO BE NEAR 1003 MB. BASED
ON IMPROVED ORGANIZATION, THE POTENTIAL FOR THE DEVELOPMENT OF A
SIGNIFICANT TROPICAL CYCLONE WITHIN THE NEXT 24 HOURS IS UPGRADED
TO GOOD.
3. THIS ALERT WILL BE REISSUED, UPGRADED TO WARNING OR CANCELLED BY
281600Z.
4. JUSTIFICATION FOR CORRECTION: ADDED TROPICAL CYCLONE FORMATION
ALERT AREA DATA TO PARA 1 AND REMARKS SECTION TO PARA 2.//
NNNN

#3 Postby **HURAKAN** » Fri Sep 28, 2007 4:10 pm

FLORIDA NEEDS THIS!!!

Incredibly this is not a TC?!?!?

LOW PRESSURE AREA 1002 HPA NEAR 16N 124E WNW 10 KT.

#4 Postby **senorpepr** » Fri Sep 28, 2007 5:12 pm

FWIW, PAGASA has this as Tropical Storm Hanna (just upgraded from a tropical depression).

Severe Weather Bulletin Number SEVEN
Tropical Cyclone WARNING: Tropical Storm "HANNA"
Issued at 5:00 AM, Saturday, 29 September 2007 Tropical Storm "HANNA" has moved west northwestward and is now off the coast of Aurora.
Location of Center:
(as of 4:00 AM) 70 kms east of Casiguran, Aurora
Coordinates: 16.3°N, 122.8°E
Strength: Maximum sustained winds of 65 kph near the center
gustiness of up to 80 kph
Movement: west northwest at 20 kph
Forecast Positions / Outlook: Sunday morning:
220 kms west of Baguio
Monday morning:
695 kms west of Baguio

Signal No. 2
(60-100 kph winds)
In Luzon...
Isabela
Quirino
Aurora
Northern Quezon
Polillio Island
Camarines Norte
Camarines Sur
Catanduanes

Signal No. 1
(30-60 kph winds)
In Luzon...
Abra
Ilocos Norte
Ilocos Sur
La Union
Pangasinan
Zambales
Tarlac
Pampanga
Bataan
Cagayan
Kalinga
Mt. Province
Ifugao
Benguet
Nueva Vizcaya
Nueva Ecija
Bulacan
Rizal
Laguna
Cavite
Batangas
Rest of Quezon
Marinduque
Burias Island
Albay
Sorsogon
Metro Manila

Residents under Public Storm Warning Signals are alerted against big waves generated by this tropical cyclone.

Tropical Storm "HANNA" is expected to weaken upon landfall.

It will continue to enhance the Southwest Monsoon which will bring rains over Visayas and Mindanao. On the other hand, Luzon will continue to experience rains due to the approaching disturbance. Those living in low lying areas and near mountain slopes are advised to take all the necessary measures against possible flashfloods and landslides.

The public and the disaster coordinating councils concerned are advised to take appropriate actions and watch for the next bulletin to be issued at 11 AM today.

#5 Postby **HURAKAN** » Fri Sep 28, 2007 5:13 pm

Makes sense based on the organization of the cloud pattern. :uarrow:

#6 Postby **CrazyC83** » Fri Sep 28, 2007 5:21 pm

Wow, not often that PAGASA goes first...

The topic should IMO say Invest 98W (PAGASA TS Hanna), clarifying that it is officially still an Invest, but a TS has been recognized by one agency.

Coredesat · #7 Postby **Coredesat** » Fri Sep 28, 2007 6:04 pm

JTWC cancelled the TCFA:

(1) THE AREA OF CONVECTION PREVIOUSLY LOCATED NEAR 14.9N
129.1E, IS NOW LOCATED NEAR 14.0N 125.7E, APPROXIMATELY 280 NM
EAST OF CAVITE, PHILIPPINES. RECENT ANIMATED INFRARED SATELLITE IMAGERY
DEPICTS A BROAD AREA OF MONSOON DEPRESSION LIKE CHARACTER, WITH CON-
VECTION FLARING ALONG THE PERIPHERIES. A 280951Z QUIKSCAT HIGH
RESOLUTION PASS SHOWS A WEAK LOW LEVEL CIRCULATION CENTER WITH STRONG
WINDS AND CONVECTION DISPLACED APPROXIMATELY 2 DEGREES FROM THE CENTER.
MAXIMUM SUSTAINED SURFACE WINDS ARE ESTIMATED AT 10 TO 15 KNOTS. MINIMUM
SEA LEVEL PRESSURE IS ESTIMATED TO BE NEAR 1004 MB. SEE REF A (WTPN21
PGTW 281600) FOR FURTHER DETAILS. THE POTENTIAL FOR THE DEVELOPMENT OF A
SIGNIFICANT TROPICAL CYCLONE WITHIN THE NEXT 24 HOURS IS DOWNGRADED TO
POOR.

I think the JTWC and JMA are looking too far east:

Chacor · #8 Postby **Chacor** » Fri Sep 28, 2007 9:23 pm

TD:

TROPICAL DEPRESSION 1000 HPA AT 17N 122E WEST 10 KT.

Coredesat · #9 Postby **Coredesat** » Fri Sep 28, 2007 10:23 pm

294
TPPN10 PGTW 290318

A. TROPICAL DISTURBANCE E OF LUZON

B. 29/0230Z

C. 15.9N/5

D. 123.3E/9

E. FIVE/MTSAT

F. T1.5/1.5/W0.5/24HRS STT: D0.5/06HRS (28/2330Z)

G. IR/EIR/VIS/MSI LLCC

49A/PBO PTLY XPSD LLCC/ANMTN.

AMES

Chacor · #10 Postby **Chacor** » Sat Sep 29, 2007 2:45 am

WTPQ20 RJTD 290600
RSMC TROPICAL CYCLONE ADVISORY
NAME TD
ANALYSIS
PSTN 290600UTC 17.0N 121.0E FAIR
MOVE W SLOWLY
PRES 998HPA
MXWD 030KT
GUST 045KT
FORECAST
24HF 300600UTC 16.0N 116.0E 150NM 70%
MOVE W 12KT
PRES 994HPA
MXWD 035KT
GUST 050KT =

WTPQ30 RJTD 290600

RSMC TROPICAL CYCLONE PROGNOSTIC REASONING
REASONING NO. 1 FOR TD LOCATED AT 17.0N 121.0E
1.GENERAL COMMENTS
POSITION FORECAST IS MAINLY BASED ON NWP AND PERSISTENCY.
2.SYNOPTIC SITUATION
NOTHING PARTICULAR TO EXPLAIN.
3.MOTION FORECAST
POSITION ACCURACY AT 290600 UTC IS FAIR.
TD WILL ACCELERATE FOR THE NEXT 24 HOURS.
TD WILL MOVE WEST FOR THE NEXT 24 HOURS.
4.INTENSITY FORECAST
TD WILL BE GRADED UP TO TS WITHIN 24 HOURS.
TD WILL DEVELOP BECAUSE CLOUD TOP TEMPERATURE NEAR CYCLONE CENTER HAS BECOME COLDER AND CYCLONE WILL STAY IN HIGH SST AREA.
FI-NUMBER WILL BE 2.5 AFTER 24 HOURS.=

Coredesat · #11 Postby **Coredesat** » Sat Sep 29, 2007 3:53 am

WTPN21 PGTW 290900
MSGID/GENADMIN/NAVPACMETOCCEN PEARL HARBOR HI/JTWC//
SUBJ/TROPICAL CYCLONE FORMATION ALERT//
RMKS/
1. FORMATION OF A SIGNIFICANT TROPICAL CYCLONE IS POSSIBLE WITHIN
145 NM EITHER SIDE OF A LINE FROM 16.1N 120.4E TO 15.8N 113.5E
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 IM-
AGERY AT 290600Z INDICATES THAT A CIRCULATION CENTER IS LOCATED
NEAR 15.9N 119.3E. THE SYSTEM IS MOVING WEST-SOUTHWESTWARD AT 15
KNOTS.
2. REMARKS:
3. THIS ALERT WILL BE REISSUED, UPGRADED TO WARNING OR CANCELLED BY
300900Z.
//

#12 Postby **P.K.** » Sat Sep 29, 2007 4:59 am

PAGASA had this as a TS for most of yesterday although RSMC Tokyo only had it as a LPA. Note the 5kt increase on the 24 hour forecast.

WTPQ20 RJTD 290900
RSMC TROPICAL CYCLONE ADVISORY
NAME TD
ANALYSIS
PSTN 290900UTC 17.0N 119.7E FAIR
MOVE W 10KT
PRES 998HPA
MXWD 030KT
GUST 045KT
FORECAST
24HF 300900UTC 15.4N 115.6E 150NM 70%
MOVE WSW 11KT
PRES 992HPA
MXWD 040KT
GUST 060KT =

Chacor · #13 Postby **Chacor** » Sat Sep 29, 2007 5:11 am

The first TCFA was for 98W. However a 90W has just appeared on NRL and it appears the TCFA is for this new 90W, also in this area.

Chacor · #14 Postby **Chacor** » Sat Sep 29, 2007 5:13 am

Here's the explanation from the JTWC STWO:

98W:
THE AREA OF CONVECTION PREVIOUSLY LOCATED NEAR 15.6N
124.0E, IS NOW LOCATED NEAR 16.6N 122.4E, APPROXIMATELY 140 NM
NORTHEAST OF MANILA. RECENT ANIMATED MULTISPECTRAL SATELLITE IMAGERY
SHOWS THE LOW LEVEL CIRCULATION CENTER (LLCC) IS EXPOSED AND REMAINS
TO THE EAST OF LUZON. ANY DEEP CONVECTION THAT WAS PREVIOUSLY
ASSOCIATED WITH THIS AREA HAS MOVED ACROSS LUZON AND APPEARS TO BE
ASSOCIATED WITH A MID LEVEL CIRCULATION THAT IS DECOUPLED THE
REMNANT LLCC. MAXIMUM SUSTAINED SURFACE WINDS ARE ESTIMATED AT 10 TO
15 KNOTS. MINIMUM SEA LEVEL PRESSURE IS ESTIMATED TO BE NEAR 1002
MB. DUE TO THE LACK OF CONVECTION OVER THIS LLCC, THE POTENTIAL FOR
THE DEVELOPMENT OF A SIGNIFICANT TROPICAL CYCLONE WITHIN THE NEXT 24
HOURS IS DOWNGRADED TO POOR.

90W:
AN AREA OF CONVECTION HAS PERSISTED NEAR 15.9N 119.3E,
APPROXIMATELY 125 NM NORTHWEST OF MANILA. RECENT ANIMATED
MULTISPECTRAL SATELLITE IMAGERY INDICATES A WELL-DEFINED MID LEVEL
CIRCULATION HAS MOVED OVER LUZON AND INTO THE SOUTH CHINA SEA. A
290117Z ASCAT PASS AND RECENT SHIP OBSERVATIONS INDICATE A LLCC MAY
BE DEVELOPING BENEATH THE MID LEVEL, ALTHOUGH THIS CANNOT BE
CONFIRMED ON SATELLITE DUE TO CONTAMINATION. THE SHIP OBSERVATIONS
AND ASCAT INDICATE WINDS IN BETWEEN 20 AND 25 KTS. A 200 MB
ANTICYCLONE OVER LUZON IS CONTRIBUTING TO EXCELLENT DIFFLUENCE ALOFT
ALONG WITH DUAL OUTFLOW CHANNELS. DEEP CONVECTION HAS DECREASED
SLIGHTLY NEAR THE CENTER OF THE CIRCULATION, MOST LIKELY DUE TO
INTERACTING WITH LAND OVER THE PAST 06 HOURS. DEEP CONVECTIVE
BANDING IS DEVELOPING IN THE NORTHEASTERN AND SOUTHWESTERN QUADRANT
OF THE DISTURBANCE. MAXIMUM SUSTAINED SURFACE WINDS ARE ESTIMATED AT
20 TO 25 KNOTS. MINIMUM SEA LEVEL PRESSURE IS ESTIMATED TO BE NEAR
1002 MB. SEE REF A (WTPN21 PGTW 290900) FOR FURTHER DETAILS. THE
POTENTIAL FOR THE DEVELOPMENT OF A SIGNIFICANT TROPICAL CYCLONE
WITHIN THE NEXT 24 HOURS IS GOOD.

Chacor · #15 Postby **Chacor** » Sat Sep 29, 2007 8:04 am

PAGASA has downgraded TS Hanna to a TD.

T1.5 from JMA at 12z.

Chacor · #16 Postby **Chacor** » Sat Sep 29, 2007 8:14 am

Weakened.

WTPQ20 RJTD 291200
RSMC TROPICAL CYCLONE ADVISORY
NAME TD
ANALYSIS
PSTN 291200UTC 16.5N 118.5E POOR
MOVE W 15KT
PRES 1000HPA
MXWD 030KT
GUST 045KT
FORECAST
24HF 301200UTC 15.1N 115.8E 150NM 70%
MOVE NW SLOWLY
PRES 992HPA
MXWD 040KT
GUST 060KT =

#17 Postby **CrazyC83** » Sat Sep 29, 2007 9:57 am

Probably weakened due to landfall.

#18 Postby **HURAKAN** » Sat Sep 29, 2007 1:44 pm

Somehow this is now 90W:

Chacor · #19 Postby **Chacor** » Sat Sep 29, 2007 8:12 pm

T2.5 from JMA, so we've probably got an upgrade.

#20 Postby **CrazyC83** » Sat Sep 29, 2007 8:16 pm

Chacor wrote:T2.5 from JMA, so we've probably got an upgrade.

Talk about a slow-builder! If the JTWC does not recognize it, do we have 90W.(name)?

WPAC: Tropical Depression LEKIMA

WPAC: Tropical Depression LEKIMA

Re: JMA TD near Philippines: Discussion (98W/PAGASA TS)

Re:

Who is online