WPAC: YUTU - Post-Tropical

[Hayabusa]

[1900hurricane]

Worth watching if you're in the Marianas for sure.

[euro6208]

Upgrades to a TS.

WDPN31 PGTW 220300
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/PROGNOSTIC REASONING FOR TROPICAL STORM 31W (YUTU)
WARNING NR 03//
RMKS//
1. FOR METEOROLOGISTS.
2. 6 HOUR SUMMARY AND ANALYSIS.
TROPICAL STORM 31W (YUTU), LOCATED APPROXIMATELY 706 NM EAST-
SOUTHEAST OF ANDERSEN AFB, HAS TRACKED WEST-NORTHWESTWARD AT 10
KNOTS OVER THE PAST SIX HOURS. ANIMATED MULTISPECTRAL SATELLITE
IMAGERY SHOWS DEEP CONVECTION WITH IMPROVED SPIRAL BANDING WRAPPING
AROUND A SOMEWHAT ELONGATED LOW-LEVEL CIRCULATION CENTER (LLCC).
THE INITIAL POSITION IS PLACED WITH FAIR CONFIDENCE BASED ON A
212314Z METOP-A 89GHZ MICROWAVE IMAGE, WHICH IS BETWEEN THE PGTW
FIX TO THE WEST AND KNES FIX TO THE EAST. THE 212316Z ASCAT
SCATTEROMETER WINDS INDICATE THAT THE WESTERN PERIPHERY OF THE
ELONGATED LLCC IS TOWARD THE PGTW FIX, WHEREAS THE DEEPEST
CONVECTION TO THE EAST WRAPPING AROUND THE MID-LEVEL CIRCULATION IS
CLOSER TO THE KNES FIX. ALL OF THIS EVIDENCE SUGGESTS THAT THE LLCC
IS SOMEWHAT ELONGATED FROM THE WEST TO EAST WITH SOME SLIGHT VORTEX
TILING DOWNSHEAR. TS 31W IS EXPERIENCING SOME LIGHT WESTERLY
VERTICAL WIND SHEAR (10-15 KNOTS), BUT WITH EXCELLENT AND IMPROVING
OUTFLOW AS THE TUTT CELL TO THE NORTHWEST GRADUALLY FILLS AND
DEAMPLIFIES. SEA SURFACE TEMPERATURES REMAIN WARM (30 TO 32 DEGREES
CELSIUS), AND THE SYSTEM IS EXPECTED TO TRAVERSE A FAVORABLE
ENVIRONMENT THAT IS CONDUCIVE FOR INTENSIFICATION AS IT TRACKS
TOWARD THE NORTHWEST AROUND THE SOUTHWESTERN PERIPHERY OF A
SUBTROPICAL RIDGE (STR).
3. FORECAST REASONING.
A. THE INTENSITY FORECAST WITHIN TAU 48 WAS INCREASED TO ACCOUNT
FOR THE LIKELIHOOD OF RAPID INTENSIFICATION, BUT OTHERWISE, THERE
IS NO CHANGE TO THE FORECAST PHILOSOPHY SINCE THE
PREVIOUS PROGNOSTIC REASONING MESSAGE.
B. THROUGH TAU 72, TS 31W WILL CONTINUE TRACKING TOWARD THE
NORTHWEST AROUND THE STR, WITH ENVIRONMENTAL CONDITIONS REMAINING
FAVORABLE FOR INTENSIFICATION. AS THE WEAK TUTT CELL TO THE
NORTHWEST FILLS, POLEWARD OUTFLOW IS EXPECTED TO DRAMATICALLY
IMPROVE, AND A PERIOD OF RAPID INTENSIFICATION IS LIKELY BETWEEN
TAUS 12 AND 48. BY TAU 72, TS 31W WILL REACH AN INTENSITY OF AT
LEAST 110 KNOTS. DYNAMIC MODEL GUIDANCE IS IN GOOD AGREEMENT THAT
TS 31W WILL TRACK NORTHWESTWARD THROUGH TAU 72, SO THERE IS HIGH
CONFIDENCE IN THIS PORTION OF THE JTWC FORECAST TRACK.
C. BEYOND TAU 72, A WEAKNESS IN THE STR INDUCED BY AN UPPER-
TROPOSPHERIC TROUGH WILL GRADUALLY TURN TS 31W SLIGHTLY MORE
POLEWARD. HOWEVER, THERE IS STILL A SIGNIFICANT SPREAD IN THE
DYNAMIC MODEL GUIDANCE IN THESE EXTENDED TAUS, WITH THE GFS-RELATED
MODEL SUITE (AVNO, AEMN, HWRF) RECURVING THE SYSTEM TOWARD THE
NORTH AWAY FROM THE MARIANAS. THE REST OF THE CONW GUIDANCE TRACKS
THE SYSTEM TOWARD AND THROUGH THE NORTHERN MARIANAS, SO THE JTWC
FORECAST TRACK IS SLIGHTLY WEST OF CONW. ENVIRONMENTAL CONDITIONS
ARE EXPECTED TO REMAIN FAVORABLE FOR INTENSIFICATION, AND TS 31W IS
FORECAST TO REACH SUPER TYPHOON INTENSITY BY THE END OF THE
FORECAST PERIOD. THE FORECAST OF 135 KNOTS AT TAU 120 IS ACTUALLY
SLIGHTLY LOWER THAN ICNW, SO DEPENDING ON WHETHER RAPID
INTENSIFICATION OCCURS IN THE SHORT TERM, THE POSSIBILITY EXISTS THAT
TS 31W WILL BECOME EVEN MORE INTENSE THAN CURRENTLY FORECAST. DUE TO
THE SIGNIFICANT SPREAD IN THE MODEL GUIDANCE AT THESE EXTENDED TAUS,
THERE IS LOW CONFIDENCE IN THIS PORTION OF THE JTWC FORECAST
TRACK.//
NNNN

[mrbagyo]

Has the potential to intensify into another 5.

[euro6208]

WDPN31 PGTW 220900
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/PROGNOSTIC REASONING FOR TROPICAL STORM 31W (YUTU)
WARNING NR 04//
RMKS//
1. FOR METEOROLOGISTS.
2. 6 HOUR SUMMARY AND ANALYSIS.
TROPICAL STORM (TS) 31W (YUTU), LOCATED APPROXIMATELY 638 NM
EAST-SOUTHEAST OF ANDERSEN AFB, GUAM, HAS TRACKED NORTHWESTWARD AT
12 KNOTS OVER THE PAST SIX HOURS. ANIMATED MULTISPECTRAL SATELLITE
IMAGERY SHOWS DEEP CONVECTION AROUND THE LOW LEVEL CIRCULATION
CENTER (LLCC) ALONG WITH AN EXPANDING CLOUD FIELD. THE INITIAL
POSITION IS PLACED WITH FAIR CONFIDENCE AND IS BASED ON A 220544Z
HMS 89GHZ MICROWAVE IMAGE WHICH SHOWS THE DEEPEST CONVECTION IS
LOCATED TO THE EAST AND THE SOUTH OF THE LLCC. THE INITIAL
INTENSITY OF 40 KNOTS IS HEDGED BETWEEN DVORAK INTENSITY ESTIMATES
OF T2.5 (35 KNOTS) FROM PGTW, KNES, AND RJTD AND A 220542Z SATCON
ESTIMATE OF 44 KNOTS AND AN ADT ESTIMATE OF T2.9 (43 KNOTS).
ENVIRONMENTAL ANALYSIS SHOWS THAT TS 31W IS EXPERIENCING FAVORABLE
VERTICAL WIND SHEAR (5 TO 10 KNOTS) AND HAS EXCELLENT RADIAL
OUTFLOW. SEA SURFACE TEMPERATURES REMAIN WARM (30 TO 32 DEGREES
CELSIUS) AND WILL ALLOW FOR CONTINUED DEVELOPMENT. TS 31W IS
TRACKING NORTHWESTWARD ALONG THE SOUTHWESTERN PERIPHERY OF
THE SUBTROPICAL RIDGE (STR) LOCATED TO THE NORTHEAST.
3. FORECAST REASONING.
A. THERE IS NO CHANGE TO THE FORECAST PHILOSOPHY SINCE THE
PREVIOUS PROGNOSTIC REASONING MESSAGE.
B. THROUGH TAU 72, TS 31W WILL CONTINUE TRACKING TOWARD THE
NORTHWEST AROUND THE AFOREMENTIONED STR, WITH ENVIRONMENTAL
CONDITIONS REMAINING FAVORABLE FOR INTENSIFICATION. MODEL GUIDANCE
IS INDICATING RAPID INTENSIFICATION WHICH SEEMS LIKELY BASED ON
FAVORABLE VERTICAL WIND SHEAR AND SEA SURFACE TEMPERATURES ALONG
WITH EXCELLENT RADIAL OUTFLOW. BY TAU 24, TS 31W WILL REACH AN
INTENSITY OF 70 KNOTS. ADDITIONAL INTENSIFICATION TO 110 KNOTS WILL
OCCUR BY TAU 72. DYNAMIC MODEL GUIDANCE CONTINUES TO SHOW A
NORTHWESTWARD TRACK THROUGH TAU 72. ADDITIONALLY, MODEL GUIDANCE
HAS COME INTO BETTER AGREEMENT WITH A SMALLER SPREAD THROUGH TAU
72. THEREFORE, THERE IS HIGH CONFIDENCE IN THIS PORTION OF THE JTWC
FORECAST TRACK.
C. BEYOND TAU 72, A WEAKNESS IN THE STR INDUCED BY AN
UPPER-TROPOSPHERIC TROUGH WILL ALLOW FOR A SLIGHTLY MORE NORTHWARD
TRACK. ENVIRONMENTAL CONDITIONS WILL REMAIN FAVORABLE FOR CONTINUED
INTENSIFICATION WITH LOW VERTICAL WIND SHEAR AND HIGH OCEAN HEAT
CONTENT. DYNAMIC MODEL GUIDANCE REMAINS IN POOR AGREEMENT BEYOND
TAU 72. AFUM AND ECMWF INDICATE A MORE WESTWARD TRACK WHILE GFS AND
NAVGEM INDICATE A CONTINUED NORTHWESTWARD TRACK. THE GFS AND ECMWF
ENSEMBLE TRACKERS ARE AT THE EDGES OF THE MODEL ENVELOPE WITH A
SPREAD OF 540NM BETWEEN THEM BY TAU 120. THE GFS ENSEMBLE FAVORS A
NORTHWARD TRACK WHILE THE ECMWF ENSEMBLE FAVORS A WESTWARD TRACK.
DUE TO THE WIDE SPREAD IN MODEL GUIDANCE BY TAU 120 THERE IS LOW
CONFIDENCE IN THIS PORTION OF THE JTWC FORECAST TRACK.//
NNNN

[euro6208]

Typhoon watches are now in effect for Tinian and Saipan.

A Tropical storm watch is now in effect for Rota.

Residents of Guam should continue to monitor the progress of Tropical Storm Yutu.

[euro6208]

Big burst.

[euro6208]

Great uncertainty in regards to track.

[Hayabusa]

[euro6208]

Now that is a big shift left for GFS after days of recurving east of the Marianas.

[Hayabusa]

Severe Tropical Storm Yutu
STS 1826 (Yutu)
Issued at 12:45 UTC, 22 October 2018

<Analysis at 12 UTC, 22 October>
Scale -
Intensity -
Center position N10°55' (10.9°)
E154°00' (154.0°)
Direction and speed of movement NW 20 km/h (12 kt)
Central pressure 990 hPa
Maximum wind speed near center 25 m/s (50 kt)
Maximum wind gust speed 35 m/s (70 kt)
≥ 30 kt wind area ALL 390 km (210 NM)

[cycloneye]

STS 1826 (Yutu)
Issued at 18:45 UTC, 22 October 2018

<Analysis at 18 UTC, 22 October>
Scale -
Intensity -
Center position N11°25' (11.4°)
E152°35' (152.6°)
Direction and speed of movement WNW 30 km/h (15 kt)
Central pressure 985 hPa
Maximum wind speed near center 30 m/s (55 kt)
Maximum wind gust speed 40 m/s (80 kt)
≥ 50 kt wind area ALL 60 km (30 NM)
≥ 30 kt wind area ALL 390 km (210 NM)

<Forecast for 18 UTC, 23 October>
Intensity -
Center position of probability circle N13°35' (13.6°)
E149°25' (149.4°)
Direction and speed of movement NW 15 km/h (9 kt)
Central pressure 955 hPa
Maximum wind speed near center 40 m/s (80 kt)
Maximum wind gust speed 60 m/s (115 kt)
Radius of probability circle 90 km (50 NM)
Storm warning area ALL 220 km (120 NM)

<Forecast for 18 UTC, 24 October>
Intensity Very strong
Center position of probability circle N15°40' (15.7°)
E146°40' (146.7°)
Direction and speed of movement NW 15 km/h (8 kt)
Central pressure 935 hPa
Maximum wind speed near center 50 m/s (95 kt)
Maximum wind gust speed 70 m/s (135 kt)
Radius of probability circle 180 km (95 NM)
Storm warning area ALL 350 km (190 NM)

<Forecast for 18 UTC, 25 October>
Intensity Violent
Center position of probability circle N17°00' (17.0°)
E143°55' (143.9°)
Direction and speed of movement WNW 15 km/h (7 kt)
Central pressure 915 hPa
Maximum wind speed near center 55 m/s (105 kt)
Maximum wind gust speed 75 m/s (150 kt)
Radius of probability circle 240 km (130 NM)
Storm warning area ALL 460 km (250 NM)

<Forecast for 18 UTC, 26 October>
Center position of probability circle N18°10' (18.2°)
E140°30' (140.5°)
Direction and speed of movement WNW 15 km/h (9 kt)
Radius of probability circle 440 km (240 NM)

<Forecast for 18 UTC, 27 October>
Center position of probability circle N19°35' (19.6°)
E136°00' (136.0°)
Direction and speed of movement WNW 20 km/h (11 kt)
Radius of probability circle 700 km (375 NM)

[euro6208]

Expecting a high end Cat 3 for Saipan.

WDPN31 PGTW 222100
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/PROGNOSTIC REASONING FOR TROPICAL STORM 31W (YUTU)
WARNING NR 06//
RMKS//
1. FOR METEOROLOGISTS.
2. 6 HOUR SUMMARY AND ANALYSIS.
TROPICAL STORM 31W (YUTU), LOCATED APPROXIMATELY 209 NM NORTH-
NORTHEAST OF CHUUK, HAS TRACKED WEST-NORTHWESTWARD AT 12 KNOTS
OVER THE PAST SIX HOURS. ANIMATED ENHANCED INFRARED (EIR) SATELLITE
IMAGERY SHOWS AN EXPANSIVE AREA OF DEEP CONVECTION LOCATED DIRECTLY
OVER AND OCCLUDING THE LOW LEVEL CIRCULATION CENTER (LLCC). THE
CONVECTIVE STRUCTURE OF THE SYSTEM HAS IMPROVED SIGNIFICANTLY OVER
THE LAST SIX HOURS AS THE SYSTEM IS CURRENTLY UNDERGOING RAPID
INTENSIFICATION (RI). THE INITIAL POSITION IS PLACED WITH GOOD
CONFIDENCE BASED ON A 221747Z 91GHZ SSMI/S MICROWAVE IMAGE THAT
SHOWS EXTENSIVE CONVECTIVE BANDING IN THE EASTERN SEMI-CIRCLE
WRAPPING INTO THE LLCC. THE INITIAL INTENSITY OF 60 KNOTS IS HEDGED
ON THE UPPER END OF DVORAK CURRENT INTENSITY ESTIMATES OF T3.5 (55
KNOTS) FROM PGTW, KNES, AND RJTD. ENVIRONMENTAL ANALYSIS SHOWS THAT
TS 31W IS IN AN AREA OF LOW (10-15 KNOT) VERTICAL WIND SHEAR AND IS
TRACKING THROUGH WARM (30-32 CELSIUS) SEA SURFACE TEMPERATURES.
UPPER LEVEL ANALYSIS SHOWS THAT THE SYSTEM HAS A GOOD POLEWARD
OUTFLOW CHANNEL AND RADIAL OUTFLOW IN THE SOUTHERN SEMI-CIRCLE. TS
31W IS CURRENTLY RAPIDLY INTENSIFYING AS IT TRACKS NORTHWESTWARD
ALONG THE SOUTHWESTERN PERIPHERY OF THE SUBTROPICAL RIDGE (STR)
LOCATED TO THE NORTHEAST.
3. FORECAST REASONING.
A. THERE IS NO CHANGE TO THE FORECAST PHILOSOPHY SINCE THE
PREVIOUS PROGNOSTIC REASONING MESSAGE.
B. THROUGH TAU 72, TS 31W IS FORECAST TO CONTINUE TRACKING
NORTHWESTWARD ALONG THE SOUTHWESTERN EDGE OF THE STR TO THE
NORTHEAST. ENVIRONMENTAL CONDITIONS WILL REMAIN VERY FAVORABLE WITH
LOW VERTICAL WIND SHEAR AND HIGH SEA SURFACE TEMPERATURES COMBINING
WITH GOOD OUTFLOW TO ALLOW FOR CONTINUED RAPID INTENSIFICATION.
INTENSIFICATION TO 120 KNOTS WILL OCCUR BY TAU 72. DYNAMIC MODEL
GUIDANCE CONTINUES TO SHOW A GENERALLY NORTHWESTWARD TRACK THROUGH
TAU 72. MODEL GUIDANCE REMAINS IN GOOD AGREEMENT WITH A SMALL SPREAD
THROUGH TAU 72. DUE TO THE TIGHT GROUPING IN THE MODEL GUIDANCE,
THERE IS HIGH CONFIDENCE IN THIS PORTION OF THE JTWC FORECAST
TRACK.
C. BEYOND TAU 72, TS 31W IS FORECAST TO CONTINUE TRACKING TO THE
NORTHWEST. ENVIRONMENTAL CONDITIONS WILL REMAIN FAVORABLE WITH LOW
TO MODERATE VERTICAL WIND SHEAR AND WARM SEA SURFACE TEMPERATURES.
THE ENVIRONMENT IS FORECAST TO BE FAVORABLE FOR ADDITIONAL
INTENSIFICATION, THOUGH NOT AT THE RAPID RATE AS SEEN IN THE NEAR
TERM FORECAST. DYNAMIC MODEL GUIDANCE BEGINS TO DIVERGE BEYOND TAU
72. THE PRINCIPLE NORTHERN OUTLIERS ARE THE GFS-ENSEMBLE AND COAMPS-
TC, WHICH FAVOR AN EARLY RECURVE TO THE NORTH EAST IMMEDIATELY AFTER
TAU 72. THE SOUTHERLY OUTLIER IS AFUM WHICH HAS THE SYSTEM TRACKING
TO THE WEST TOWARDS LUZON BY TAU 120. THE JTWC FORECAST TRACK IS
PLACED TO THE SOUTH OF THE MULTI-MODEL CONSENSUS TO OFFSET THE
INFLUENCE OF THE GFS-ENSEMBLE SINCE THE EARLY RECURVE IS UNLIKELY.
HOWEVER, DUE TO THE WIDE SPREAD IN MODEL GUIDANCE BY TAU 120 THERE
STILL IS LOW CONFIDENCE IN THIS PORTION OF THE JTWC FORECAST TRACK.//
NNNN

[euro6208]

Morning visible

[Highteeld]

Looks like a real whopper will evolve out of this in a the near term.

[xtyphooncyclonex]

Euro ensembles
https://i.imgur.com/Yms73jP.png
But we all know the Euro failed miserably in tracking Trami and Kong-rey

[/quote]
Not so fast! I guess this time, the ECMWF is prevailing. Both the JMA and JTWC have shifted to the left significantly, and the GFS has begun to cave in to the ECMWF...

[euro6208]

TPPN10 PGTW 230026

A. TROPICAL STORM 31W (YUTU)

B. 23/0000Z

C. 11.33N

D. 151.56E

E. FIVE/HMWRI8

F. T4.0/4.0/D2.0/24HRS STT: S0.0/03HRS

G. IR/EIR/VIS/MSI

H. REMARKS: 40A/PBO SBC/ANMTN. CNVCTN WRAPS .90 ON LOG10 SPIRAL
WITH A PLUS 0.5 ADJUSTMENT FOR W BANDING, YIELDING A DT OF 4.0.
MET/PT AGREE. DBO DT.

I. ADDITIONAL POSITIONS: NONE


MILAM

[xtyphooncyclonex]

TY 1826 (Yutu)
Issued at 00:45 UTC, 23 October 2018

<Analysis at 00 UTC, 23 October>
Scale -
Intensity -
Center position N11°50' (11.8°)
E151°30' (151.5°)
Direction and speed of movement WNW 20 km/h (12 kt)
Central pressure 975 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 90 km (50 NM)
≥ 30 kt wind area ALL 390 km (210 NM)

<Forecast for 12 UTC, 23 October>
Intensity -
Center position of probability circle N13°05' (13.1°)
E149°55' (149.9°)
Direction and speed of movement NW 20 km/h (10 kt)
Central pressure 965 hPa
Maximum wind speed near center 40 m/s (75 kt)
Maximum wind gust speed 55 m/s (105 kt)
Radius of probability circle 60 km (30 NM)
Storm warning area ALL 170 km (90 NM)

<Forecast for 00 UTC, 24 October>
Intensity Very strong
Center position of probability circle N14°00' (14.0°)
E148°20' (148.3°)
Direction and speed of movement WNW 15 km/h (9 kt)
Central pressure 950 hPa
Maximum wind speed near center 45 m/s (85 kt)
Maximum wind gust speed 60 m/s (120 kt)
Radius of probability circle 90 km (50 NM)
Storm warning area ALL 240 km (130 NM)

<Forecast for 00 UTC, 25 October>
Intensity Very strong
Center position of probability circle N16°00' (16.0°)
E145°30' (145.5°)
Direction and speed of movement NW 15 km/h (8 kt)
Central pressure 925 hPa
Maximum wind speed near center 50 m/s (100 kt)
Maximum wind gust speed 70 m/s (140 kt)
Radius of probability circle 180 km (95 NM)
Storm warning area ALL 370 km (200 NM)

<Forecast for 00 UTC, 26 October>
Intensity Violent
Center position of probability circle N17°05' (17.1°)
E142°35' (142.6°)
Direction and speed of movement WNW 15 km/h (7 kt)
Central pressure 915 hPa
Maximum wind speed near center 55 m/s (105 kt)
Maximum wind gust speed 75 m/s (150 kt)
Radius of probability circle 240 km (130 NM)
Storm warning area ALL 460 km (250 NM)

[euro6208]

0Z BT at 65 knots. We have Typhoon Yutu.

[Highteeld]

Woot.