WPAC: 04W - Post-Tropical

[euro6208]

97W INVEST
As of 00:00 UTC May 03, 2018:

Location: 6.2°N 153.0°E
Maximum Winds: 15 kt
Minimum Central Pressure: 1010 mb



New invest within the robust surface trough.

[wxman57]

Looks more like it's part of 96W. Development looks unlikely, as 96W should be the main feature.

[euro6208]

97W INVEST
As of 12:00 UTC May 03, 2018:

Location: 6.2°N 153.8°E
Maximum Winds: 15 kt
Minimum Central Pressure: 1010 mb

[euro6208]

Interestingly EURO develops this more than GFS.

[wxman57]

Interestingly EURO develops this more than GFS.

To me, it looks like the Euro develops 96W and doesn't even see a separate 97W.

[euro6208]

AN AREA OF CONVECTION (INVEST 97W) HAS PERSISTED NEAR 6.2N
153.8E, APPROXIMATELY 135 NM EAST-SOUTHEAST OF CHUUK. ANIMATED
ENHANCED INFRARED SATELLITE IMAGERY DEPICTS FLARING CONVECTION
TURNING IN THE MIDLEVELS ABOVE A BROAD LLC. A 031124Z METOP-A ASCAT
PASS SHOWS A REGION OF SHARP LOW-LEVEL TROUGHING, WITH THE MIDLEVEL
MESOCYCLONE DISPLACED TO THE NORTHWEST. 97W IS CURRENTLY IN A BAND OF
LOW (10-15KT) VWS WITH HIGHER VALUES TO THE NORTH. SSTS ARE WARM (27-
29C) AND WILL SUPPORT FURTHER DEVELOPMENT. GLOBAL MODELS SHOW
INTERACTION BETWEEN 97W AND 96W WITH GOOD AGREEMENT, BUT VARY ON
TROPICAL DEVELOPMENT POTENTIAL AS THE SYSTEM TRACKS NORTHWEST.
MAXIMUM SUSTAINED SURFACE WINDS ARE ESTIMATED AT 15 TO 20 KNOTS.
MINIMUM SEA LEVEL PRESSURE IS ESTIMATED TO BE NEAR 1010 MB. THE
POTENTIAL FOR THE DEVELOPMENT OF A SIGNIFICANT TROPICAL CYCLONE
WITHIN THE NEXT 24 HOURS IS LOW.

[euro6208]

Already Kwajalein has recorded 11 inches. Incredible.

Models are beginning to zero in on the circulation west of Pohnpei
near 6N154E as the dominant circulation along the trough axis snaking
through Micronesia. The circulation is expected to drift northwest to
north the next several days while slowly becoming better organized.
Presently, abundant heavy showers and thunderstorms are all found
away from the center of the circulation...north of Chuuk, north and
south of Pohnpei, and also near Kosrae. Chuuk, Pohnpei, and Kosrae
will all see showers and thunderstorms today, but stormy weather may
persist at Pohnpei through Saturday. Chuuk could see additional
showers early next week pending on the slow northward motion of the
circulation that would place convergent west to southwesterly flow
over the area. For Majuro, fair weather today will give way to
isolated showers and thunderstorms over the weekend as a trade-wind
trough reaches the area.

[euro6208]

AN AREA OF CONVECTION (INVEST 97W) PREVIOUSLY LOCATED NEAR
6.2N 153.8E, IS NOW LOCATED NEAR 8.7N 153.0E, APPROXIMATELY 99 NM
NORTHEAST OF CHUUK. ANIMATED ENHANCED INFRARED SATELLITE IMAGERY
DEPICTS FLARING CONVECTION WITH BROAD MIDLEVEL TURNING SURROUNDING
THE LLC. A 040000Z METOP-A PARTIAL ASCAT PASS SHOWS BROAD TURNING.
ADDITIONALLY, A 040244Z AMSR2 89GHZ MICROWAVE IMAGE DISPLAYS
DISORGANIZED CONVECTION AROUND THE LLC. 97W IS CURRENTLY IN A BAND
OF LOW (10-15KT) VWS WITH HIGHER VALUES TO THE NORTH AND GOOD
DIFFLUENCE ALOFT. SSTS ARE WARM (27-29C) AND WILL SUPPORT FURTHER
DEVELOPMENT. GLOBAL MODELS VARY IN DEVELOPMENT OF THE SYSTEM WITH
SOME MODELS INDICATING NO DEVELOPMENT AND OTHERS MODELS, GFS AND
NAVGEM, SHOWING WEAK, SLOW DEVELOPMENT AS THE SYSTEM TRACKS
NORTHWEST. MAXIMUM SUSTAINED SURFACE WINDS ARE ESTIMATED AT 15 TO 20
KNOTS. MINIMUM SEA LEVEL PRESSURE IS ESTIMATED TO BE NEAR 1007 MB.
THE POTENTIAL FOR THE DEVELOPMENT OF A SIGNIFICANT TROPICAL CYCLONE
WITHIN THE NEXT 24 HOURS REMAINS LOW.

[euro6208]

EURO and GFS doesn't do anything significant with this.

[euro6208]

The Marianas are back in a dry season pattern, for now... There is a
monsoon disturbance to our east, about 350 miles away. The models do
bring it somewhat closer. The key will be, how much closer. The new
GFS run clips Guam with it, starting Saturday late morning or after
noon. While it is not visible outside the office, went ahead and
began showing this trend by having a 16 PoP tonight (rounds to 20),
followed by 17 PoP for the CNMI tomorrow and 24 for Guam. While
these also round to 20, this is meant as an internal reminder for the
next shift to take another look.

After the monsoon disturbance moves away from the Marianas, the seas
and winds diminish. Winds could become light to gentle, and seas
could diminish to between 3 and 5 feet after the forecast period.
This could make for an ideal time at the beach for next weekend. The
chance for this thing to develop into a tropical cyclone soon is low.
Right now the 24 hour sea level pressure change in the Marianas is
rising and the wind shear east of is also increasing. Not the best
set of circumstances for an aspiring TC.

[euro6208]

[euro6208]

AN AREA OF CONVECTION (INVEST 97W) PREVIOUSLY LOCATED NEAR
8.7N 153.0E, IS NOW LOCATED NEAR 11.0N 151.8E, APPROXIMATELY 440 NM
EAST-SOUTHEAST OF GUAM. ANIMATED ENHANCED INFRARED SATELLITE IMAGERY
DISPLAYS AN ELONGATED, WEAKLY DEFINED LLC WITH A 042337Z MHS METOP-A
89GHZ MICROWAVE IMAGE SHOWING MINIMAL CONVECTION ASSOCIATED WITH THE
SYSTEM. 97W IS CURRENTLY IN A BAND OF LOW (10-15KT) VWS WITH HIGHER
VALUES TO THE NORTH AND GOOD DIFFLUENCE ALOFT. SSTS ARE WARM (27-
29C) HOWEVER, AS THE SYSTEM TRACKS NORTHWARD IT WILL ENCOUNTER
COOLER SSTS WHICH WILL INHIBIT DEVELOPMENT. GLOBAL MODELS ARE IN
GOOD AGREEMENT DEPICTING SLIGHT WEAK, SLOW DEVELOPMENT DUE TO POOR
ENVIRONMENTAL CONDITIONS AS THE SYSTEM TRACKS NORTH. MAXIMUM
SUSTAINED SURFACE WINDS ARE ESTIMATED AT 15 TO 20 KNOTS. MINIMUM SEA
LEVEL PRESSURE IS ESTIMATED TO BE NEAR 1008 MB. THE POTENTIAL FOR
THE DEVELOPMENT OF A SIGNIFICANT TROPICAL CYCLONE WITHIN THE NEXT 24
HOURS REMAINS LOW.

[euro6208]

97W INVEST
As of 06:00 UTC May 05, 2018:

Location: 11.7°N 152.1°E
Maximum Winds: 20 kt
Minimum Central Pressure: 1006 mb

[euro6208]

THE AREA OF CONVECTION (INVEST 97W) PREVIOUSLY LOCATED
NEAR 11.7N 152.1E, IS NOW LOCATED NEAR 13.3N 154.1E, APPROXIMATELY
378 NM NORTH-NORTHEAST OF CHUUK. ANIMATED MULTISPECTRAL SATELLITE
IMAGERY DISPLAYS AN ELONGATED, BROAD, ILL-DEFINED LLC TO THE WEST OF
FLARING CONVECTION. A 052316Z MHS METOP-A 89GHZ MICROWAVE IMAGE
SHOWS MINIMAL DEEP CONVECTION AND BROAD LOW LEVEL TURNING. 97W IS
CURRENTLY IN A BAND OF LOW (10-15 KT) VWS WITH HIGHER VALUES TO THE
NORTH AND MARGINAL DIFFLUENCE ALOFT. SSTS ARE WARM (27-29 DEGREES
CELSIUS) AND CURRENTLY FAVORABLE FOR DEVELOPMENT. HOWEVER, AS THE
SYSTEM TRACKS NORTHWARD IT WILL ENCOUNTER COOLER SSTS, WHICH WILL
INHIBIT DEVELOPMENT. GLOBAL MODELS VARY IN THEIR FORECASTS FOR 97W.
NAVGEM FLATTENS 97W INTO A WESTWARD TRACK TO THE SOUTH OF STRONG
MIDLATITUDE RIDGING, WHILE GFS AND ECMWF PRESENT A BREAK IN THE
RIDGE AT LATER TAUS, ALLOWING THE CIRCULATION TO MOVE NORTHWARD.
MOST MODELS DO NOT DEPICT 97W REACHING TROPICAL STORM STRENGTH,
THOUGH GRADIENT WINDS BETWEEN IT AND THE RIDGING TO THE NORTH MAY
LEAD TO HIGHER STRAIGHTLINE WIND SPEEDS. MAXIMUM SUSTAINED SURFACE
WINDS ARE ESTIMATED AT 15 TO 20 KNOTS. MINIMUM SEA LEVEL PRESSURE IS
ESTIMATED TO BE NEAR 1009 MB. THE POTENTIAL FOR THE DEVELOPMENT OF A
SIGNIFICANT TROPICAL CYCLONE WITHIN THE NEXT 24 HOURS REMAINS LOW.

[euro6208]

[euro6208]

TXPQ23 KNES 061809
TCSWNP
CCA

A. TROPICAL DISTURBANCE (97W)

B. 06/1430Z

C. 14.2N

D. 154.8E

E. THREE/HIMAWARI-8

F. T1.0/1.0/D1.0/24HRS

G. IR/EIR/SWIR

H. REMARKS...CORRECTION BASED ON 06/1626Z GMI PASS INDICATING LLCC LIES
UNDER THE COLD OVERCAST. THIS INTENSITY ESTIMATE WAS DERIVED USING 4
KM IR DATA. CURVED BANDING WRAPS .25 FOR DT=1.0. MET AND PT=1.0. FT IS
BASED ON DT.

I. ADDL POSITIONS

NIL


...VELASCO

[euro6208]

[wxman57]

LLC is well west of the convection, near 13.3N, 153.3E. Good ASCAT hit. Weak LLC swirl a few hundred miles west of the convection.

[euro6208]

THE AREA OF CONVECTION (INVEST 97W) PREVIOUSLY LOCATED
NEAR 13.3N 154.1E, IS NOW LOCATED NEAR 13.3N 153.4E, APPROXIMATELY
365 NM NORTH-NORTHEAST OF CHUUK. ANIMATED MULTISPECTRAL SATELLITE
IMAGERY DISPLAYS AN IMPROVED YET STILL ELONGATED, FULLY-EXPOSED LLC
TO THE WEST OF FLARING CONVECTION. A 062353Z MHS METOP-B 89GHZ
PARTIAL MICROWAVE IMAGE SHOWS MINIMAL DEEP CONVECTION AND BROAD LOW
LEVEL TURNING. A 062256Z METOP-A ASCAT IMAGE REVEALS A DEFINED
CIRCULATION WITH 10-15 KNOT WINDS SURROUNDING THE LLC WITH STRONGER
WINDS, 20-25 KNOTS, DISPLACED TO THE NORTH DUE TO STRAIGHT LINE
GRADIENT FLOW. 97W IS CURRENTLY IN A BAND OF MODERATE (10-20 KT) VWS
WITH HIGHER VALUES TO THE NORTH AND IMPROVING OUTFLOW ALOFT. SSTS
ARE WARM (27-29 DEGREES CELSIUS) AND CURRENTLY FAVORABLE FOR
DEVELOPMENT. HOWEVER, AS THE SYSTEM TRACKS NORTHWARD IT WILL
ENCOUNTER COOLER SSTS, WHICH WILL INHIBIT DEVELOPMENT. GLOBAL MODELS
MOSTLY AGREE ON THEIR FORECAST TRACK, MOVING 97W TO THE WEST-
NORTHWEST. DEVELOPMENT OF THE SYSTEM IS STILL FAIRLY WEAK ACROSS ALL
MODELS AS ENVIRONMENTAL CONDITIONS REMAIN UNFAVORABLE IN THE
SURROUNDING AREA. MAXIMUM SUSTAINED SURFACE WINDS ARE ESTIMATED AT
15 TO 20 KNOTS. MINIMUM SEA LEVEL PRESSURE IS ESTIMATED TO BE NEAR
1007 MB. THE POTENTIAL FOR THE DEVELOPMENT OF A SIGNIFICANT TROPICAL
CYCLONE WITHIN THE NEXT 24 HOURS REMAINS LOW.

[euro6208]

TXPQ23 KNES 070318
TCSWNP

A. TROPICAL DISTURBANCE (97W)

B. 07/0230Z

C. 13.1N

D. 153.1E

E. THREE/HIMAWARI-8

F. TOO WEAK

G. IR/EIR/VIS

H. REMARKS...THIS ESTIMATE WAS DERIVED USING 4 KM IR DATA. EXPOSED,
WELL DEFINED CENTER LOCATED GT 1.25 DEG FROM CONVECTION YIELDS A DT OF
0. MET AND PT ARE LT 1.0. THIS SYSTEM IS TOO WEAK TO CLASSIFY. THIS WILL
BE THE FINAL BULLETIN UNLESS REGENERATION OCCURS.

I. ADDL POSITIONS

NIL


...RAMIREZ