WPAC: MOLAVE - Post-Tropical

[ejeraldmc]

Molave's rainbands covering the entire country

[NewbieAboutcyclones]

Looks like a solid Cat 2. Imo

[euro6208]

That's cute. They actually average out the numbers. Problem is they are grossly underestimated by 30 to 45 knots. When you have a rapidly intensifying system, you should discount the lower numbers.

WDPN32 PGTW 250900
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/PROGNOSTIC REASONING FOR TROPICAL STORM 21W (MOLAVE) WARNING
NR 006//
RMKS/
1. FOR METEOROLOGISTS.
2. 6 HOUR SUMMARY AND ANALYSIS.
TROPICAL STORM (TS) 21W (MOLAVE), LOCATED APPROXIMATELY 238 NM
EAST-SOUTHEAST OF MANILA, PHILIPPINES, HAS TRACKED WESTWARD AT 14
KNOTS (KTS) OVER THE PAST SIX HOURS. ANIMATED MULTISPECTRAL
SATELLITE
IMAGERY INDICATES A RAPIDLY CONSOLIDATING SYSTEM WITH TIGHTLY-CURVED
BANDING WRAPPING INTO A DEFINED LOW LEVEL CIRCULATION CENTER (LLCC).
A
250525Z GMI 89 GHZ MICROWAVE IMAGE SHOWS CONVECTIVE BANDING WRAPPING
TIGHTLY INTO THE CLEARLY-DEFINED LLCC; THE 37 GHZ IMAGE DEPICTS A
SYMMETRIC MICROWAVE EYE FEATURE, SUPPORTING THE INITIAL POSITION
WITH
GOOD CONFIDENCE. THE INITIAL INTENSITY IS ASSESSED AT 60 KTS HEDGED
BETWEEN DVORAK CURRENT INTENSITY ESTIMATES OF T3.5 (55 KTS, RJTD)
AND
T4.0 (65 KTS, PGTW/KNES). FURTHERMORE, A 250610Z ADVANCED DVORAK
TECHNIQUE ESTIMATE OF T3.5 (55 KTS) AND A 250340Z SATCON ESTIMATE OF
63 KTS LEND CONFIDENCE TO THIS INTENSITY. ENVIRONMENTAL ANALYSIS
REVEALS EXCELLENT EQUATORWARD OUTFLOW AND IMPROVING POLEWARD
OUTFLOW,
LOW TO MODERATE (15-20 KTS) VERTICAL WIND SHEAR, AND WARM (29-30
CELSIUS) SEA SURFACE TEMPERATURES (SST) CONTRIBUTING TO AN OVERALL
FAVORABLE ENVIRONMENT FOR CONTINUED DEVELOPMENT. TS 21W IS TRACKING
WESTWARD UNDER THE STEERING INFLUENCE OF A SUBTROPICAL RIDGE (STR)
POSITIONED TO THE NORTHEAST WITH AN EXTENSION TO THE NORTH.
3. FORECAST REASONING.
A. THERE IS NO CHANGE TO THE FORECAST PHILOSOPHY SINCE THE
PREVIOUS
PROGNOSTIC REASONING MESSAGE.
B. TS 21W IS EXPECTED TO CONTINUE INTENSIFYING AS IT TRACKS
GENERALLY WESTWARD ALONG THE PERIPHERY OF THE STR. AS FAVORABLE
CONDITIONS PERSIST, THE SYSTEM SHOULD INTENSIFY TO 65 KTS PRIOR TO
MAKING LANDFALL OVER THE EASTERN PHILIPPINES NEAR TAU 06. AS IT
TRANSITS OVER THE INNER SEAS SOUTH OF LUZON, THE SYSTEM SHOULD
MAINTAIN INTENSITY UNTIL THE SYSTEM RE-EMERGES OVER THE SOUTH CHINA
SEA WHERE IT IS EXPECTED TO RE-INTENSIFY. TS 21W IS EXPECTED TO
INTENSIFY TO PEAK AT 85 KTS BY TAU 60 AND THEN GRADUALLY WEAKEN AS
IT
APPROACHES THE COAST. NUMERICAL GUIDANCE IS IN GOOD AGREEMENT
THROUGH
TAU 72 WITH A 112 NM SPREAD IN SOLUTIONS AT TAU 72. CONSEQUENTLY,
THERE IS HIGH CONFIDENCE IN THIS PHASE OF THE FORECAST.
C. SHORTLY AFTER TAU 72, NUMERICAL GUIDANCE DIVERGES SLIGHTLY AS
THE SYSTEM MAKES LANDFALL OVER CENTRAL VIETNAM. TS 21W WILL WEAKEN
SIGNIFICANTLY AS IT TRACKS INLAND OVER RUGGED TERRAIN. DUE TO THE
TIGHTER AGREEMENT BETWEEN THE MODELS, THERE IS OVERALL HIGH
CONFIDENCE
IN THE JTWC FORECAST TRACK.//
NNNN

[NotoSans]

Virac recording 981mb at the edge of the eye (w/ 31kt winds at that time) means the central pressure is about 975mb. So there’s indeed underestimation going on but this pressure (based on normal WPR) probably does NOT support category 2 intensity.

Of course there’d be ppl arguing that some storms depart from WPR but the modern WPR is an empirical relationship developed based on recon data.

[mrbagyo]

The captain knows how to navigate around the typhoon.

[mrbagyo]

UW - CIMSS
ADVANCED DVORAK TECHNIQUE
ADT-Version 9.0
Tropical Cyclone Intensity Algorithm

----- Current Analysis -----
Date : 25 OCT 2020 Time : 084000 UTC
Lat : 13:24:02 N Lon : 124:19:42 E


CI# /Pressure/ Vmax
4.3 / 979.9mb/ 72.2kt


Final T# Adj T# Raw T#
4.3 4.3 3.8

Center Temp : -83.6C Cloud Region Temp : -80.6C

Scene Type : UNIFORM CDO CLOUD REGION w/ MW EYE

[NotoSans]

JMA upgrades to typhoon.

[doomhaMwx]

SLP at Virac synop station already down to 985.8 mb as of 3pm PhT (07Z).

Update: Down to 981mb at 08Z.

978.4 mb at 09Z.

AAXX 25091 98446 21456 80716 10256 20251 39738 49784 55160 76566 8472/ 333 56199 60387 84716 88456

Station: VIRAC (40 m - 13 35N - 124 12E)

Synop, reported by a manned station.

Day: 25/10/2020
Hour: 09 UTC

Air Temperature : +25.6ºC
Dew point: +25.1ºC
Air relative humidity: 97%

Station pressure: 973.8 Hpa
Sea level pressure: 978.4 Hpa
Pressure change: 16.0 Hpa, Decreasing, then increasing; resultant pressure lower

Wind direction: 65º-74º (east).
Wind speed: 16 m/s (57.6 Km/h), from anemometer.

Horizontal visibility: 6.0 kilometers.

Total cloud cover: 8 eighths
Height above ground of cloud base of lowest cloud seen : 300 to 600 m
Low clouds: stratus or cumulus fractus (bad weather). (Cover: 4 eighths).
Middle clouds: altostratus opacus or nimbostratus.
High clouds: unobserved due to darkness, obscuration or to a continuous cloud layer in a lower level.
Layer of stratus (St) , height of cloud base 480 m, cover: 4 eighths.
Layer of altostratus (As) , height of cloud base 1800 m, cover: 8 eighths.
Coming direction of low clouds: northeast.
Coming direction of middle clouds: unknown (or invisible clouds).
Coming direction of high clouds: unknown (or invisible clouds).

Present weather: continuous heavy rain.
Past weather: rain.

Precipitation: 38.0 mm in the last 3 hours.

[euro6208]

Down to 3.5 again.

TPPN12 PGTW 250940

A. TROPICAL STORM 21W (MOLAVE)

B. 25/0900Z

C. 13.37N

D. 124.21E

E. FIVE/HMWRI8

F. T3.5/4.0/D2.0/24HRS STT: W0.5/03HRS

G. IR/EIR

H. REMARKS: 38A/PBO SBC/ANMTN. CNVCTN WRAPS 1.0 ON LOG10 SPIRAL
YIELDING A DT OF 3.5.

I. ADDITIONAL POSITIONS:
25/0525Z 13.40N 124.97E GPMI
25/0732Z 13.37N 124.37E SSMS


YOUNG

[Hayabusa]

TY 2018 (Molave)
Issued at 09:45 UTC, 25 October 2020

<Analysis at 09 UTC, 25 October>
Scale -
Intensity -
Center position N13°25' (13.4°)
E124°20' (124.3°)
Direction and speed of movement W 30 km/h (15 kt)
Central pressure 980 hPa
Maximum wind speed near center 35 m/s (65 kt)
Maximum wind gust speed 50 m/s (95 kt)
≥ 50 kt wind area ALL 75 km (40 NM)
≥ 30 kt wind area NE 220 km (120 NM)
SW 165 km (90 NM)

[mrbagyo]

Landfall over Tabaco Albay.
 https://twitter.com/dost_pagasa/status/1320311995938213888

[NewbieAboutcyclones]

https://www.facebook.com/51399192197316 ... 386165184/

[mrbagyo]

Guinobatan, Albay AWS (elev - 72 feet)


https://www.wunderground.com/dashboard/pws/IGUINOBA2/graph/2020-10-25/2020-10-25/daily

[mrbagyo]

Minimum pressure given by JMA and JTWC are higher than actual.
Pressure in Albay is sub 975 mb

[euro6208]

21W MOLAVE 201025 1200 13.5N 123.0E WPAC 65 987

[1900hurricane]

Using a 975 mb pressure, I get just under 85 kt using KZC with all the other stuff from JTWC in the 12Z best track.

[mrbagyo]

yikes

[ElectricStorm]

JTWC finally upgraded to a typhoon... AFTER landfall. Seriously that doesn't even make any sense

[aspen]

Molave does not care that it’s over land. This is by far the deepest convection I’ve seen since Amphan, maybe even Halong.

[ElectricStorm]

Molave does not care that it’s over land. This is by far the deepest convection I’ve seen since Amphan, maybe even Halong.
https://rammb-data.cira.colostate.edu/tc_realtime/products/storms/2020wp21/4kmsrbdc/2020wp21_4kmsrbdc_202010251700.jpg

Wow, just think if that could wrap all the way around in the SCS