EPAC: INVEST 96E - Discussion

[Subtrop]

EP, 96, 2025070412, , BEST, 0, 127N, 1020W, 20, 1009, DB, 34, NEQ, 0, 0, 0, 0, 1011, 120, 60, 0, 0, E, 0, , 0, 0, INVEST, S, 0, , 0, 0, 0, 0, genesis-num, 009, SPAWNINVEST, ep792025 to ep962025,

https://ftp.nhc.noaa.gov/atcf/btk/bep962025.dat

[cycloneye]

The first longtracker of 2025.

[cycloneye]

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
1100 AM PDT Fri Jul 4 2025

For the eastern and central North Pacific east of 180 longitude:

1. South of Southwestern Mexico (EP96):
A large area of disorganized showers and thunderstorms, partly
associated with a tropical wave, is centered a few hundred miles
south of southern and southwestern Mexico. Gradual development of
this system is expected during the next few days, and a tropical
depression is likely to form late this weekend or early next week
while it moves generally west-northwestward well off the coast of
Mexico.
* Formation chance through 48 hours...medium...50 percent.
* Formation chance through 7 days...high...80 percent.



Forecaster Cangialosi/Beven

[Yellow Evan]

12z GFS has this straddling the 26C isotherm in light easterly shear early next week, which is generally conducive for the development of an annular hurricane. I have/had reservations that the GFS has been organizing too fast and moves this too slowly, resulting in an unrealistically high intensity, but thunderstorm activity has quickly organized over the last few hours.

[cycloneye]

Central East Pacific (EP96):
A large area of disorganized showers and thunderstorms, partly
associated with a tropical wave, is centered a few hundred miles
south of southwestern Mexico. Gradual development of this system is
anticipated during the next few days, and a tropical depression is
expected to form late this weekend or early next week while it moves
generally west-northwestward well off the coast of Mexico.
* Formation chance through 48 hours...medium...60 percent.
* Formation chance through 7 days...high...90 percent.

[Kingarabian]

12z GFS has this straddling the 26C isotherm in light easterly shear early next week, which is generally conducive for the development of an annular hurricane. I have/had reservations that the GFS has been organizing too fast and moves this too slowly, resulting in an unrealistically high intensity, but thunderstorm activity has quickly organized over the last few hours.

Annular cane candy incoming

[cycloneye]

To be a longtracker, the ridge has to be strong. Will it be that way?

[cycloneye]

Hurricane models like HAFS, HWRF and HMON are not too bullish on this first run of them.

EP, 96, 2025070500, , BEST, 0, 137N, 1038W, 25, 1009, DB

[cycloneye]

TCFA issued

WTPN21 PHNC 050130
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE FORMATION ALERT//
RMKS/
1. FORMATION OF A SIGNIFICANT TROPICAL CYCLONE IS POSSIBLE WITHIN
100 NM EITHER SIDE OF A LINE FROM 13.6N 103.7W TO 14.9N 107.2W
WITHIN THE NEXT 12 TO 24 HOURS. AVAILABLE DATA DOES NOT JUSTIFY
ISSUANCE OF NUMBERED TROPICAL CYCLONE WARNINGS AT THIS TIME.
WINDS IN THE AREA ARE ESTIMATED TO BE 23 TO 28 KNOTS. METSAT
IMAGERY AT 050000Z INDICATES THAT A CIRCULATION CENTER IS LOCATED
NEAR 13.7N 103.8W. THE SYSTEM IS MOVING WEST-NORTHWESTWARD AT 09
KNOTS.
2. REMARKS: AN AREA OF CONVECTION (INVEST 96E) IS LOCATED NEAR 13.7N
103.8W, APPROXIMATELY 296NM SOUTHWEST OF ACAPULCO, MEXICO.
ANIMATED MULTISPECTRAL SATELLITE IMAGERY AND A 0411954Z 89GHZ AMSR2
IMAGE DEPICT A CONSOLIDATING, ELONGATED LOW LEVEL CIRCULATION (LLC)
WITH SPARSE DEEP CONVECTION AND CONVECTIVE BANDING TO THE WESTERN
PERIPHERY OF THE CIRCULATION. ENVIRONMENTAL ANALYSIS INDICATES A
FAVORABLE AREA FOR DEVELOPMENT DEFINED BY FAIR DIFFLUENT OUTFLOW ALOFT,
LOW TO MODERATE (15-20KT) VERTICAL WIND SHEAR, AND WARM (29-30C)
SEA SURFACE TEMPERATURES. GLOBAL MODELS ARE IN AGREEMENT THAT INVEST
96E WILL MOVE GENERALLY WEST-NORTHWESTWARD OVER THE NEXT 24-48 HOURS.
MAXIMUM SUSTAINED SURFACE WINDS ARE ESTIMATED AT 23 TO 28 KNOTS.
MINIMUM SEA LEVEL PRESSURE IS ESTIMATED TO BE NEAR 1001 MB. THE
POTENTIAL FOR THE DEVELOPMENT OF A SIGNIFICANT TROPICAL CYCLONE
WITHIN THE NEXT 24 HOURS IS HIGH.
3. THIS ALERT WILL BE REISSUED, UPGRADED TO WARNING OR CANCELLED BY
060130Z.
//

[Yellow Evan]

12z GFS has this straddling the 26C isotherm in light easterly shear early next week, which is generally conducive for the development of an annular hurricane. I have/had reservations that the GFS has been organizing too fast and moves this too slowly, resulting in an unrealistically high intensity, but thunderstorm activity has quickly organized over the last few hours.

As soon as I say this, 18z GFS comes in uch weaker and has the current convective structure fading early tomorrow. EPS also ticked down today.

[DorkyMcDorkface]

12z GFS has this straddling the 26C isotherm in light easterly shear early next week, which is generally conducive for the development of an annular hurricane. I have/had reservations that the GFS has been organizing too fast and moves this too slowly, resulting in an unrealistically high intensity, but thunderstorm activity has quickly organized over the last few hours.

As soon as I say this, 18z GFS comes in uch weaker and has the current convective structure fading early tomorrow. EPS also ticked down today.

When I saw you mention the "A" word I got excited...but yeah, I don't like the tick down in intensity from the guidance this evening. Was excited to see if we'd get something like that out of this but now I'm not so sure...

[cycloneye]

I think the cause of the models to back down on development has been the movement more north in latitud and that does not bode well for hurricane intensity because it will have less warm waters to move thru.

[cycloneye]

Central East Pacific (EP96):
A large area of disorganized showers and thunderstorms is associated
with a trough of low pressure located a few hundred miles south of
southwestern Mexico. Gradual development of this system is
anticipated during the next few days, and a tropical depression is
likely to form late this weekend or early next week while it moves
generally west-northwestward well off the coast of Mexico.
* Formation chance through 48 hours...medium...60 percent.
* Formation chance through 7 days...high...80 percent.

[Kingarabian]

Models have really backed off

[Kingarabian]

Looks like a developing TC on VIS

[cycloneye]

Going down and with the dead end sentence.

Central East Pacific (EP96):
Disorganized showers and thunderstorms located a few hundred miles
southwest of Manzanillo, Mexico, are associated with a trough of low
pressure. Gradual development of this system is anticipated during
the next couple days, and a tropical depression is likely to form by
early next week while it moves generally west-northwestward well off
the coast of Mexico. By early Tuesday, the disturbance is expected
to reach cooler water, ending its opportunity for development.
* Formation chance through 48 hours...medium...60 percent.
* Formation chance through 7 days...high...70 percent.

[cycloneye]

Central East Pacific (EP96):
Disorganized showers and thunderstorms located several hundred miles
southwest of Manzanillo, Mexico, are associated with a trough of low
pressure. Some slow development is still possible during the next
day or two, and a short-lived tropical depression could form before
the system moves west-northwestward over progressively cooler water
by Monday night.
* Formation chance through 48 hours...medium...50 percent.
* Formation chance through 7 days...medium...50 percent.

[cycloneye]

1. Central East Pacific (EP96):
An area of low pressure has become a little better defined about
400 miles southwest of the coast of southwestern Mexico. However,
the associated showers and thunderstorms remain disorganized. This
system could still become a short-lived tropical depression before
it moves into unfavorable environmental conditions on Monday.
* Formation chance through 48 hours...medium...40 percent.
* Formation chance through 7 days...medium...40 percent.

[cycloneye]

The end is almost here.

[cycloneye]

Central East Pacific (EP96):
Disorganized showers and thunderstorms associated with an area of
low pressure located several hundred miles south-southwest of the
southern tip of the Baja California peninsula continue this morning.
Some additional development is possible today, but the system is
quickly running out of time as it moves west-northwestward into a
more stable environment, with drier mid-level air and progressively
cooler waters expected by tonight.
* Formation chance through 48 hours...low...20 percent.
* Formation chance through 7 days...low...20 percent.