WPAC: MEGI (1013/15W) - Tropical Depression

[Macrocane]

Cloud tops warming up a bit.

Yes, it seems like the period of rapid intensification has ended now it may intenisy a little more at a slower pace or suffer some weakening because of EWRC.

[supercane]

Does anyone has a map graphic that shows the city of Tugearo in northen Luzon, where our Storm2k friend Typhoon Hunter will chase Megi?

Tuguegarao City, from their website.

[GCANE]

Cloud tops warming up a bit.

http://www.ssd.noaa.gov/mtsat/flt/t2/flash-ft.html

Does it suggest weakening?

Usually does.

Rain-rate is high on the eyewall.

Maybe downdraft from the high-rain rate is limiting somewhat inflow of high theta-e air into the core.

Boundary layer air cools somewhat from a strong eyewall cell downdraft.

[oaba09]

From PAGASA:
AS OF 10:00 AM TODAY (SUNDAY, 17 OCTOBER 2010), TYPHOON “JUAN” WAS LOCATED AT 520 KM EAST OF APARRI, CAGAYAN (18.7°N, 127.0°E).

MAXIMUM SUSTAINED WINDS: 195 KPH NEAR THE CENTER
GUSTINESS: UP TO 230 KPH
FORECAST MOVEMENT: WESTWARD
SPEED: 22 KPH
ESTIMATED CENTRAL PRESSURE: 938 hPa

[Macrocane]

Does anyone know why some agencies are not using the central pressure found by the RECON?

[supercane]

WDPN31 PGTW 170300
MSGID/GENADMIN/NAVMARFCSTCEN PEARL HARBOR HI/JTWC//
SUBJ/PROGNOSTIC REASONING FOR SUPER TYPHOON 15W (MEGI) WARNING NR
17//
RMKS/
1. FOR METEOROLOGISTS.
2. 12 HOUR SUMMARY AND ANALYSIS.
A. SUPER TYPHOON (STY) 15W (MEGI), LOCATED APPROXIMATELY 450 NM
NORTHEAST OF MANILA, PHILIPPINES, HAS TRACKED WESTWARD AT
12 KNOTS OVER THE PAST SIX HOURS. ANIMATED MULTISPECTRAL SATELLITE
IMAGERY AND A 162254Z SSMIS 91H MICROWAVE IMAGE DEPICT A WELL-
DEFINED 15 NM EYE WITH A CONCENTRIC EYE WALL AND EXCELLENT RADIAL
OUTFLOW. THERE IS HIGH CONFIDENCE IN THE CURRENT POSITION BASED ON
RJTD AND PGTW 17/00Z EYE FIXES. OVER THE PAST 12 HOURS, SUPER
TYPHOON MEGI HAS UNDERGONE RAPID INTENSIFICATION. THE CURRENT
INTENSITY IS BASED ON DVORAK INTENSITY ESTIMATES 0F 140 KNOTS FROM
PGTW AND RJTD, CIMSS SATELLITE CONSENSUS ESTIMATES OF 137 KNOTS AT
16/22Z, AND AN AIRCRAFT VORTEX MESSAGE AT 16/2339Z INDICATING
MAXIMUM OBSERVED SURFACE WINDS OF 120 KNOTS, MINIMUM SEA LEVEL
PRESSURE OF 908 MB (EQUIVALENT TO 153 KNOT VMAX ON THE KNAFF-ZEHR
SCALE), AND MAXIMUM OUTBOUND SURFACE WINDS OF 146 KNOTS. UPPER LEVEL
ANALYSIS REVEALS A SLIGHT WEAKENING IN POLEWARD OUTFLOW, HOWEVER
EQUATORWARD OUTFLOW INTO AN UPPER LEVEL LOW TO THE EAST REMAINS
VIGOROUS. THE TRACK HAS FLATTENED OUT AND STY MEGI IS NOW TRACKING
WESTWARD UNDER THE INFLUENCE A DEEP-LAYER SUBTROPICAL STEERING RIDGE.
3. FORECAST REASONING.
A. THE FORECAST INTENSITY HAS BEEN INCREASED IN RESPONSE TO THE
PAST 12 HOURS OF RAPID INTENSIFICATION.
B. STY MEGI IS FORECAST TO CONTINUE TRACKING WESTWARD TO WEST-
SOUTHWESTWARD TOWARD LUZON AND MAY INTENSIFY SLIGHTLY WITHIN THE
NEXT 12 TO 24 HOURS. THE SYSTEM IS EXPECTED TO MAKE LANDFALL OVER
NORTHERN LUZON WITHIN THE NEXT 24 TO 36 HOURS AT SUPER TYPHOON
INTENSITY AND WEAKEN CONSIDERABLY AS IT TRACKS ACROSS THE
MOUNTAINOUS TERRAIN. AFTER TAU 36, STY MEGI WILL RE-EMERGE IN THE
SOUTH CHINA SEA AT TYPHOON INTENSITY AND BEGIN TO STEADILY RE-
INTENSIFY.
C. NEAR TAU 72, STY MEGI IS FORECAST TO SLOW AND TURN POLEWARD
TOWARD A WEAKNESS IN THE SUBTROPICAL STEERING RIDGE ASSOCIATED WITH
A SHORTWAVE MID-LATITUDE TROUGH PROPAGATING EASTWARD ACROSS CENTRAL
ASIA. NUMERICAL MODEL GUIDANCE HAS COME INTO EVEN BETTER AGREEMENT
FROM THE PREVIOUS FORECAST, HOWEVER THERE IS SOME SPREAD IN THE
MODELS AFTER TAU 72 AS TO THE TIMING OF THE POLEWARD TURN TOWARD
SOUTHERN CHINA. THIS FORECAST IS IN CLOSE AGREEMENT WITH MODEL
CONSENSUS.//
NNNN

[StormingB81]

Wow winds right now 160 mph! thats insane

[CrazyC83]

169kt FL + dropsonde shows 152kt at surface (00918 08652).

145 to 150kt (1-min) IMO.

Based on that and all available data, I would put the intensity at 150 kt. May have peaked at 155 kt earlier.

[oaba09]

FROM PAGASA



Signal No.3
(100-185 kph winds)
Cagayan
Calayan Group of Islands
Babuyan Group of Islands
Isabela

Signal No. 2
(60-100 kph winds)
Batanes group of Islands
Ilocos Norte
Ilocos Sur
Apayao
Abra
Kalinga
Mountain Province
Ifugao
Nueva Vizcaya
Quirino
Northern Aurora

Signal No. 1
(30-60 kph winds)
La Union
Benguet
Pangasinan
Nueva Ecija
Rest of Aurora

[RobWESTPACWX]

Does anyone know why some agencies are not using the central pressure found by the RECON?

Well, this may sound ignorant and kind of silly, but ever think that maybe some of the agencies can't read the recon or how to get the site with the recon since it's in english? Just food for thought....

[CrazyC83]

Does anyone know why some agencies are not using the central pressure found by the RECON?

Well, this may sound ignorant and kind of silly, but ever think that maybe some of the agencies can't read the recon or how to get the site with the recon since it's in english? Just food for thought....

That is very possible. The real intensity is likely 908mb/150 kt right now.

[phwxenthusiast]

169kt FL + dropsonde shows 152kt at surface (00918 08652).

145 to 150kt (1-min) IMO.

Based on that and all available data, I would put the intensity at 150 kt. May have peaked at 155 kt earlier.

so you think it's not gonna strengthen anymore?? still roughly 12-18hrs to go before landfall though, i dont know...

[supercane]

Latest KNES Dvorak still T7.0:

TXPN23 KNES 170330
SIMWIR
A. 15W (MEGI)
B. 17/0257Z
C. 18.6N
D. 126.7E
E. ONE/MTSAT
F. T7.0/7.0/D2.0/24HRS
G. IR/EIR/VIS/SSMIS/TMI
H. REMARKS...WARM MEDIUM GREY EYE EMBEDDED IN WHITE RING GIVING DT OF
7.0. MET IS A 6.5. PT IS A 7.0. FT BASED ON DT.
I. ADDL POSITIONS
16/2323Z 18.7N 127.8E SSMIS
16/2336Z 18.7N 127.6E TMI
...NEWHARD
=

415
TCNA20 RJTD 170300
CCAA 17030 47644 MEGI(1013) 17187 11268 113/4 2//// 92713=

[Anonymous_daw]

Does anyone know why some agencies are not using the central pressure found by the RECON?

Well, this may sound ignorant and kind of silly, but ever think that maybe some of the agencies can't read the recon or how to get the site with the recon since it's in english? Just food for thought....

Hi there, sad to say, there is also the possibility that some agencies are arrogant (like our govt weather agency IMO). that's why it's good and im grateful that there are websites like this which give info from various sources to provide a better overall picture of the situation

[CrazyC83]

169kt FL + dropsonde shows 152kt at surface (00918 08652).

145 to 150kt (1-min) IMO.

Based on that and all available data, I would put the intensity at 150 kt. May have peaked at 155 kt earlier.

so you think it's not gonna strengthen anymore?? still roughly 12-18hrs to go before landfall though, i dont know...

With the tiny eye, an eyewall replacement cycle might begin soon. Also storms rarely maintain such an extreme intensity for very long. Still a storm with 175 mph winds is EXTREMELY dangerous, capable of total destruction.

[phwxenthusiast]

Hi there, sad to say, there is also the possibility that some agencies are arrogant (like our govt weather agency IMO). that's why it's good and im grateful that there are websites like this which give info from various sources to provide a better overall picture of the situation

you've nailed it!! yes PAGASA is known to be somewhat arrogant... they stick to their forecasts, their methods, and reasoning etc... but when questioned about their imprecise forecasts, they're gonna complain about their old equipments... i mean come on, we have the internet... all it takes is a couple of computers, go to the web, and get more sources...!!

[supercane]

JMA 03Z update up to 115kt:

WTPQ20 RJTD 170300
RSMC TROPICAL CYCLONE ADVISORY
NAME TY 1013 MEGI (1013)
ANALYSIS
PSTN 170300UTC 18.7N 126.8E GOOD
MOVE W 12KT
PRES 910HPA
MXWD 115KT
GUST 165KT
50KT 110NM
30KT 220NM EAST 180NM WEST
FORECAST
24HF 180300UTC 17.9N 122.3E 75NM 70%
MOVE W 11KT
PRES 910HPA
MXWD 115KT
GUST 165KT
45HF 190000UTC 16.5N 117.7E 160NM 70%
MOVE WSW 12KT
PRES 945HPA
MXWD 085KT
GUST 120KT
69HF 200000UTC 16.5N 115.1E 210NM 70%
MOVE W 06KT
PRES 940HPA
MXWD 085KT
GUST 120KT =

[oaba09]

115 knots



TY 1013 (Megi)

[Macrocane]

JMA central pressure is closer to the real value, it would be great if in a near future all the agencies could share data from the recon and other observations, thanks for all the answers to my question.

[CrazyC83]

JMA rounds it to the nearest 5mb though.