WPAC: VONGFONG - Post-Tropical

[doomhaMwx]

ECMWF is still among the few models which are more south than the rest of the guidance. Few or none of its ensemble members even get Vongfong to typhoon intensity though, which may be resulting/contributing to a southward bias in their storm tracks. Nonetheless, Vongfong's movement during the next 24hrs should be closely watched.

https://i.imgur.com/r0PPeXp.png
https://i.imgur.com/06wNrv6.png

Still couldnt wrap my head around the fact that Euro's output could be improved with an accurate initialization...I dont know how things work in running weather models using supercomputers but I thought initialization is just merely inputing parameters, I have no idea how someone can do wrong with that.

It might be due to the storm's small/compact size like your earlier guess. Even GFS has done this in some small TCs before.

[dexterlabio]

It might be due to the storm's small/compact size like your earlier guess. Even GFS has done this in some small TCs before.

In this case though the GFS has resolved the issue with this storm's small nature. This might be one of those few instances where the GFS wins over the Euro in the model war.

[Hayabusa]

[dexterlabio]

Call me crazy but at this rate this could have a shot at STY status, especially if Vongfong tracks further to the north away from Eastern Visayas and Bicol peninsula.

[Jay Typhoon]

2020-05-13 12:00 UTC

- Vongfong (2001) -
Position: 12.12N 127.86E
CI: 4.5 | DT: 3.5
MET: 3.5 | PT: 4.5
FT: 4.5

[ejeraldmc]

Yesterday I thought the storm looked pathetic. Now it's trying to become a significant storm in May!

[cycloneye]

[WAcyclone]

A 0911 UTC SMAP pass of Vongfong yielded 62 kt 1-minute winds. Note that this was just before the apparent rapid intensification phase based on IR imagery.

[Hayabusa]

90 kt

TPPN10 PGTW 131202

A. TYPHOON 01W (VONGFONG)

B. 13/1130Z

C. 12.08N

D. 127.94E

E. THREE/HMWRI8

F. T5.0/5.0/D3.0/24HRS STT: D1.0/03HRS

G. IR/EIR

H. REMARKS: 09A/PBO RAGGED EYE/ANMTN. OW EYE SURROUNDED BY LG
YIELDS AN E# OF 5.0. ADDED 0.5 EYE ADJUSTMENT FOR B, TO YIELD A
DT OF 5.5. PT YIELDS A 5.0 AND MET 4.5. DBO PT. CONSTRAINTS
BROKEN WHICH LIMIT CHANGE TO 2.5 OVER 24HRS.

I. ADDITIONAL POSITIONS:
13/0823Z 12.08N 128.38E SSMS


HEINS

[Hayabusa]

85 kt peak in koba scale so means cat 3

TY 2001 (Vongfong)
Issued at 12:40 UTC, 13 May 2020

<Analysis at 12 UTC, 13 May>
Scale -
Intensity -
Center position N12°05' (12.1°)
E127°55' (127.9°)
Direction and speed of movement WNW 10 km/h (6 kt)
Central pressure 975 hPa
Maximum wind speed near center 35 m/s (70 kt)
Maximum wind gust speed 50 m/s (100 kt)
≥ 50 kt wind area ALL 75 km (40 NM)
≥ 30 kt wind area NE 220 km (120 NM)
SW 165 km (90 NM)

<Forecast for 12 UTC, 14 May>
Intensity -
Center position of probability circle N12°40' (12.7°)
E125°05' (125.1°)
Direction and speed of movement W 15 km/h (7 kt)
Central pressure 960 hPa
Maximum wind speed near center 40 m/s (80 kt)
Maximum wind gust speed 60 m/s (115 kt)
Radius of probability circle 95 km (50 NM)
Storm warning area ALL 175 km (95 NM)

<Forecast for 12 UTC, 15 May>
Intensity Very strong
Center position of probability circle N14°35' (14.6°)
E122°10' (122.2°)
Direction and speed of movement WNW 15 km/h (8 kt)
Central pressure 955 hPa
Maximum wind speed near center 45 m/s (85 kt)
Maximum wind gust speed 60 m/s (120 kt)
Radius of probability circle 165 km (90 NM)
Storm warning area ALL 260 km (140 NM)

<Forecast for 12 UTC, 16 May>
Intensity Very strong
Center position of probability circle N17°50' (17.8°)
E120°35' (120.6°)
Direction and speed of movement NNW 15 km/h (9 kt)
Central pressure 955 hPa
Maximum wind speed near center 45 m/s (85 kt)
Maximum wind gust speed 60 m/s (120 kt)
Radius of probability circle 260 km (140 NM)
Storm warning area ALL 350 km (190 NM)

<Forecast for 12 UTC, 17 May>
Intensity -
Center position of probability circle N20°50' (20.8°)
E122°35' (122.6°)
Direction and speed of movement NNE 15 km/h (9 kt)
Central pressure 975 hPa
Maximum wind speed near center 35 m/s (70 kt)
Maximum wind gust speed 50 m/s (100 kt)
Radius of probability circle 370 km (200 NM)
Storm warning area ALL 430 km (230 NM)

<Forecast for 12 UTC, 18 May>
Intensity -
Center position of probability circle N25°35' (25.6°)
E129°05' (129.1°)
Direction and speed of movement NE 35 km/h (19 kt)
Central pressure 992 hPa
Maximum wind speed near center 25 m/s (50 kt)
Maximum wind gust speed 35 m/s (70 kt)
Radius of probability circle 650 km (360 NM)

[aspen]

Based on the current RI phase, I think we could see at least a 110-115 kt Cat 3/4 typhoon by the 00z advisory.

[1900hurricane]

A 0911 UTC SMAP pass of Vongfong yielded 62 kt 1-minute winds. Note that this was just before the apparent rapid intensification phase based on IR imagery.

https://i.imgur.com/6iAbpbC.jpg

I wonder if SMAP's resolution is challenged by Vongfong's small size in this case. SMAP has proven to be pretty good even in smaller TCs despite its resolution limitations, but the fix data for that pass (below) only has an average r34 of 36 nm. When down to this size, SMAP may have some struggles, as similar sized TCs like Banyan '17 or Ambali '19 seem to indicate. For what it's worth, an AMSU pass from NOAA-19 at almost the same time (0915Z) resulted in an 81 kt/975 mb estimate (also below), and in this case, I think I am more inclined to lean towards that estimate.

WP, 01, 202005130911, 30, SMAP, IR, , 1220N, 12790E, , 1, 55, 1, , , , 34, NEQ, 47, 51, 23, 23, , , , , 1, 0, , , NASA, RSS, , , , , , , , , , , , , , , , , , , , , , , , , , , , 1, max. wind is 10 minute sustained
WP, 01, 202005130911, 30, SMAP, IR, , 1220N, 12790E, , 1, 55, 1, , , , 50, NEQ, 31, 0, 0, 0, , , , , 1, 0, , , NASA, RSS, , , , , , , , , , , , , , , , , , , , , , , , , , , , 1, max. wind is 10 minute sustained
WP, 01, 202005130911, 30, SMAP, IR, , 1220N, 12790E, , 1, 55, 1, , , , 64, NEQ, 0, 0, 0, 0, , , , , 1, 0, , , NASA, RSS, , , , , , , , , , , , , , , , , , , , , , , , , , , , 1, max. wind is 10 minute sustained

CIMSS/NESDIS-USAF/NRL AMSU TC Intensity Estimation:
TYPHOON 01W
Wednesday 13may20 Time: 0915 UTC
Latitude: 12.15 Longitude: 128.15
Storm position corresponds to AMSU-A FOV 20 [1<--->30]
-----------------------------------------------------------------
| Estimated MSLP: 975 hPa
| Estimated Maximum Sustained Wind: 81 kts
| Estimate Confidence: Good ( +/- 7mb +/- 8kts )
-----------------------------------------------------------------
Storm is sub-sampled: Bias correction applied is -10.2 hPa
Channel 8 (~150 hPa) Tb Anomaly: -0.75228
Channel 7 (~250 hPa) Tb Anomaly: 0.984
RMW: 14 km
RMW Source is: IR
Environmental Pressure: 1007
Satellite: NOAA-19
ATCF data for Month: 05 Day: 13 Time (UTC): 0600

For imagery, go to http://amsu.ssec.wisc.edu
For all comments and questions mailto:chrisv@ssec.wisc.edu

[dexterlabio]

There could be some slight hiccup as Vongfong's eye disappeared in the latest sat frames. Could this be due to core structural changes or dry air issue?

[1900hurricane]

Looks like the eye is reestablishing itself already.

[TheHurricaneGod]

The JTWC is expecting a category four peak on Vongfong.

[1900hurricane]

The JTWC short term intensity forecast is very close to the HWFI.

[aspen]

There could be some slight hiccup as Vongfong's eye disappeared in the latest sat frames. Could this be due to core structural changes or dry air issue?

Well, it is quite a small system, so any large burst of convection has the potential to cloud the eye for a short time. It’s already trying to reopen.

[Yellow Evan]

Dvorak numbers oscillating but likely a major or near major at this point.

[Highteeld]

Looks like a dry air intrusion is hurting it quite a bit right now/encumbrance to growth

[Hayabusa]

Nice track UKMET...