WPAC: MARIA - Post-Tropical

[1900hurricane]

I'll agree that the setup looks impressive. Outflow is good to all quadrants, and the primary feeder band is tapping from the monsoon trough. We are getting the rare opportunity of watching the development and possibly maturation of a tropical cyclone from a radar scope.

[1900hurricane]

Here we go, JMA is in the process of upgrading their graphics. We now have Tropical Storm Maria.

[cycloneye]

I regret talking about this name for obvious reason but is here.

TS 1808 (Maria)
Issued at 13:20 UTC, 4 July 2018

<Analysis at 12 UTC, 4 July>
Scale -
Intensity -
Center position N12°25' (12.4°)
E146°10' (146.2°)
Direction and speed of movement N Slow
Central pressure 1002 hPa
Maximum wind speed near center 18 m/s (35 kt)
Maximum wind gust speed 25 m/s (50 kt)
≥ 30 kt wind area NE 220 km (120 NM)
SW 170 km (90 NM)

<Forecast for 12 UTC, 5 July>
Intensity -
Center position of probability circle N14°40' (14.7°)
E144°25' (144.4°)
Direction and speed of movement NW 15 km/h (7 kt)
Central pressure 992 hPa
Maximum wind speed near center 23 m/s (45 kt)
Maximum wind gust speed 35 m/s (65 kt)
Radius of probability circle 90 km (50 NM)

<Forecast for 12 UTC, 6 July>
Intensity -
Center position of probability circle N17°00' (17.0°)
E142°25' (142.4°)
Direction and speed of movement NW 15 km/h (7 kt)
Central pressure 980 hPa
Maximum wind speed near center 30 m/s (60 kt)
Maximum wind gust speed 45 m/s (85 kt)
Radius of probability circle 180 km (95 NM)
Storm warning area ALL 240 km (130 NM)

<Forecast for 12 UTC, 7 July>
Intensity Strong
Center position of probability circle N19°00' (19.0°)
E141°25' (141.4°)
Direction and speed of movement NNW 10 km/h (6 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 240 km (130 NM)
Storm warning area ALL 350 km (190 NM)

[euro6208]

Already seeing 40 mph gust on Guam.

[NotoSans]

I would say JMA’s intensity forecast is a bit too conservative.

[1900hurricane]

Agree with that. They're going about a T per day or just under it looks like, or about the climatological rate. I think it should be faster than that. First forecasts can tend to be conservative though.

[euro6208]

Not sure if i'm reading this right but HWRF keeps this as a +Cat 3 major or higher for close to 4 days. Serious ACE here.

[mrbagyo]

That long feeder band to the SW looks amazing. Reminds me of Hurricane Marie (EPAC) and other classic WPac systems.
That's a steady supply of moisture/energy.

[euro6208]

[mrbagyo]

Long range Radar Loop

[cycloneye]

JTWC 15:00 UTC warning on Tropical Storm Maria.Peak is 100 kts and Okinawa may be in the track.

WDPN32 PGTW 041500
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/PROGNOSTIC REASONING FOR TROPICAL STORM 10W (MARIA) WARNING
NR 08//
RMKS//
1. FOR METEOROLOGISTS.
2. 6 HOUR SUMMARY AND ANALYSIS.
TROPICAL STORM 10W (MARIA), LOCATED APPROXIMATELY 68 NM SOUTH-
SOUTHEAST OF ANDERSEN AFB, HAS TRACKED WEST-NORTHWESTWARD AT 08
KNOTS OVER THE PAST SIX HOURS. ANIMATED ENHANCED INFRARED SATELLITE
IMAGERY SHOWS TS MARIA IS BECOMING INCREASINGLY ORGANIZED WITH
FLARING CENTRAL DENSE OVERCAST OBSCURING ITS LOW LEVEL CIRCULATION
CENTER. THE INITIAL POSITION IS PLACED WITH HIGH CONFIDENCE BASED
ON RADAR FIXES FROM PGTW AND PGUM. THE INITIAL INTENSITY OF 35
KNOTS IS BASED ON THE PGTW CURRENT INTENSITY ESTIMATE OF T2.5 (35
KTS), ABOVE THE RJTD ESTIMATE OF T1.5 (25 KTS). OBSERVATIONS FROM
ANDERSON AFB (PGUA) RECORD WINDS OF 27 KTS GUSTING TO 39 KTS, WHILE
THE SYSTEM CENTER IS STILL 63NM AWAY. ENVIRONMENTAL ANALYSIS SHOWS
TS 10W IS EXPERIENCING FAVORABLE TO MODERATE VERTICAL WIND SHEAR
(15 TO 20 KNOTS). TROPICAL UPPER TROPOSPHERIC TROUGH (TUTT) CELLS
LOCATED TO THE NORTHEAST AND TO THE NORTHWEST ARE ENHANCING
POLEWARD OUTFLOW, ALLOWING FOR FLARING DEEP CONVECTION. SEA SURFACE
TEMPERATURES REMAIN FAVORABLE FOR DEVELOPMENT, RANGING BETWEEN 30
AND 31 DEGREES CELSIUS. TS MARIA RECENTLY JOGGED TOWARDS THE WEST-
NORTHWEST, AND IS BEING STEERED BY THE SUBTROPICAL RIDGE (STR)
LOCATED TO THE NORTH.
3. FORECAST REASONING.
A. THERE IS NO CHANGE IN THE FORECAST PHILOSOPHY SINCE THE
PREVIOUS PROGNOSTIC REASONING MESSAGE. HOWEVER, HIGH UNCERTAINTY
REMAINS REGARDING THE TRACK OF TS MARIA.
B. TS MARIA WILL CONTINUE TO TRACK TO THE NORTHWEST THROUGH TAU
48 AS IT TRACKS AROUND THE SOUTHWESTERN PERIPHERY OF THE STR
LOCATED TO THE NORTH. MODEL GUIDANCE STILL VARIES GREATLY IN THE
POSITIONING AND STRENGTH OF THE STR TO THE NORTH AS A WESTERLY
MIDLATITUDE TROUGH MOVES THROUGH AND ERODES THE TROUGH. MESOSCALE
MODELS INDICATE RAPID INTENSIFICATION IS LIKELY IN THE NEXT 24
HOURS. THE JTWC FORECAST TRACK IS HEDGED JUST TO THE WEST OF THE
MULTI-MODEL CONSENSUS, FAVORING THE ECMWF SOLUTION THAT FEATURES A
MORE WESTWARD COMPONENT THAN MOST OF THE OTHER NUMERICAL MODELS.
DUE TO THE WIDE RANGE IN MODEL SOLUTIONS, THERE IS LOW CONFIDENCE
IN THIS PORTION OF THE JTWC FORECAST TRACK.
C. BEYOND TAU 72, THERE IS SIGNIFICANT SPREAD IN MODEL GUIDANCE,
WITH A RANGE OF LONG-TERM SOLUTIONS DEPICTING TS 10W PASSING
SOMEWHERE BETWEEN OKINAWA OR THE ISLAND OF HONSHU, JAPAN. THE
NAVGEM MODEL INDICATES THAT THE STR WILL NOT REBUILD AFTER THE
TROUGH MOVES THROUGH, ALLOWING A CONSISTENTLY NORTHWESTERLY TRACK.
HOWEVER, THE NAVGEM SOLUTION HAS BEGUN TO CONVERGE TOWARDS THE BULK
OF MODEL GUIDANCE ON THE LAST MODEL RUN. THE GFS DEPICTS THE
WEAKENED STR AND A MORE NORTHWARD TRACK INITIALLY AS WELL, FOLLOWED
BY A BUILDING OF THE STR INTO THE AREA, LEADING TO A TURN TO THE
NORTHWEST. THE ECMWF DETERMINISTIC TRACKER ALSO PROJECTS A
NORTHWESTERLY TURNING TO WEST-NORTHWESTERLY TRACK AS THE STR BUILDS
BACK IN. DUE TO THE WIDE RANGE IN MODEL SOLUTIONS THERE IS HIGH
UNCERTAINTY IN THE TRACK FOR TS MARIA. THEREFORE, THERE IS OVERALL
LOW CONFIDENCE IN THE JTWC FORECAST TRACK.//

[euro6208]

Time for bed. See you all in a couple hours.

[mrbagyo]

Convection is now getting thicker/ more dense.

[mrbagyo]

40 knots wind is just offshore of Guam.

[Ed_2001]

Sustained TS winds and a gust of 49mph reported on Guam.
https://w1.weather.gov/data/obhistory/PGUM.html

[cycloneye]

SAB up to 3.0:

TXPQ21 KNES 041518
TCSWNP

A. 10W (MARIA)

B. 04/1430Z

C. 12.9N

D. 145.3E

E. THREE/HIMAWARI-8

F. T3.0/3.0/D2.0/24HRS

G. IR/EIR/SWIR

H. REMARKS...THIS INTENSITY ESTIMATE WAS DERIVED USING 4 KM IR
DATA. SYSTEM HAS DEVELOPED RAPIDLY OVER THE LAST 24 HOURS RESULTING IN
A MET OF 2.5, WHICH WAS ADJUSTED TO 3.0 IN DEFINING THE PT. DT IS ALSO
3.0 BASED ON 5/10 BANDING WITH 0.5 ADDED BECAUSE THE BAND WAS WHITE. FT
IS BASED ON DT.

I. ADDL POSITIONS

NIL


...TURK

[cycloneye]

@nissenwx
Speak of the devil. I think it's safe to say #Maria might be entering a period of RI.

[mrbagyo]

999.3 mb in Andersen AFB

SPECI PGUA 041611Z COR AUTO 06034G45KT 5SM -RA OVC007 24/24 A2954 RMK AO2 VIS 1 RWY06L VIS 5/8 RWY24L VIS 3/8 RWY24R SLP993 RVRNO CHINO RWY24L $ COR 1625

[1900hurricane]

Yeah, might be putting together a small core based on radar data. Also interesting to note the tight mesocyclone rotating in the band north of the main center.

 https://twitter.com/1900hurricane/status/1014549040820834304




 https://twitter.com/1900hurricane/status/1014555942153842689

[mrbagyo]

Obs in Andersen AFB will be interesting once that meso ( if ever) reached Yigo.

Pressure in AAFB now down to 998.6