EPAC: INVEST 91E - Discussion

[Subtrop]

EP, 91, 2025101418, , BEST, 0, 120N, 925W, 30, 1008, DB, 34, NEQ, 0, 0, 0, 0, 1009, 150, 100, 0, 0, E, 0, , 0, 0, INVEST, S, 0, , 0, 0, 0, 0, genesis-num, 031, SPAWNINVEST, ep742025 to ep912025,

https://ftp.nhc.noaa.gov/atcf/btk/bep912025.dat

[cycloneye]

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
500 PM PDT Tue Oct 14 2025


1. South of Southern Mexico (EP91):
A broad area of low pressure is producing a large area of
disorganized showers and thunderstorms near the coast of southern
Mexico and portions of Central America. Environmental conditions
appear conducive for gradual development, and a tropical depression
could form late this week or over the weekend. This system is
expected to move little during the next few days, but a slow
northwestward motion near the coast of southern and southwestern
Mexico is expected by the weekend.
* Formation chance through 48 hours...low...30 percent.
* Formation chance through 7 days...medium...60 percent.

[AJC3]

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
1100 PM PDT Tue Oct 14 2025


South of Southern Mexico (EP91):
A broad area of low pressure is producing a large area of
disorganized showers and thunderstorms near the coast of southern
Mexico and portions of Central America. Environmental conditions
appear conducive for gradual development, and a tropical depression
could form late this week or over the weekend. This system is
expected to move little during the next few days, but a slow
northwestward motion near the coast of southern and southwestern
Mexico is expected by the weekend.
* Formation chance through 48 hours...medium...40 percent.
* Formation chance through 7 days...medium...60 percent.

[cycloneye]

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
1100 AM PDT Wed Oct 15 2025

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

1. South of Southern Mexico (EP91):
A broad area of low pressure is producing some disorganized showers
and thunderstorms offshore of southern Mexico and portions of
Central America. Environmental conditions appear conducive for
gradual development of this disturbance, and a tropical depression
could form late this week or over the weekend. The system is
forecast to move little during the next couple of days, but a slow
west-northwestward or northwestward motion near the coast of
southern and southwestern Mexico is expected by the weekend.
* Formation chance through 48 hours...medium...40 percent.
* Formation chance through 7 days...medium...60 percent.



Forecaster Reinhart

[cycloneye]

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
500 AM PDT Thu Oct 16 2025

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

South of Southern Mexico (EP91):
A broad area of low pressure is producing some disorganized showers
and thunderstorms offshore of southern Mexico. Environmental
conditions appear conducive for gradual development of this
disturbance, and a tropical depression could form during the next
few days. The system is forecast to move slowly west-northwestward
or northwestward near the coast of southern and southwestern Mexico
through the weekend.
* Formation chance through 48 hours...medium...50 percent.
* Formation chance through 7 days...medium...60 percent.

$$
Forecaster Bucci

[cycloneye]

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
500 PM PDT Thu Oct 16 2025

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

1. South of Southern Mexico (EP91):
A broad area of low pressure is producing some disorganized showers
and thunderstorms offshore of southern Mexico. Environmental
conditions appear conducive for gradual development of this
disturbance, and a tropical depression could form during the next
couple of days or so. The system is forecast to move slowly
west-northwestward or northwestward near the coast of southern and
southwestern Mexico through the weekend.
* Formation chance through 48 hours...medium...50 percent.
* Formation chance through 7 days...medium...50 percent.



Forecaster Gibbs

[cycloneye]

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
500 AM PDT Fri Oct 17 2025

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

1. South of Southern Mexico (EP91):
A broad area of low pressure is producing some disorganized showers
and thunderstorms offshore of southern Mexico. Environmental
conditions appear conducive for gradual development of this
disturbance, and a tropical depression could form during the next
couple of days or so. The system is forecast to move slowly
west-northwestward or northwestward near the coast of southern and
southwestern Mexico through the weekend.
* Formation chance through 48 hours...medium...40 percent.
* Formation chance through 7 days...medium...40 percent.



Forecaster Bucci

[cycloneye]

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
1100 AM PDT Fri Oct 17 2025

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

1. South of Southern Mexico (EP91):
Shower and thunderstorm activity has decreased significantly during
the past day in association with a broad area of low pressure off
the coast of southern Mexico. However, some gradual development is
still possible while the system moves slowly west-northwestward or
northwestward near the coast of southern and southwestern Mexico
through the weekend.
* Formation chance through 48 hours...low...20 percent.
* Formation chance through 7 days...low...20 percent.



Forecaster Bucci

[cycloneye]

TWOEP

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
500 PM PDT Fri Oct 17 2025

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

South of Southern Mexico (EP91):
Shower and thunderstorm activity associated with a broad area of low
pressure off the coast of southern Mexico remains limited and
disorganized. Development of this system is unlikely during the next
couple of days as it drifts slowly westward or west-northwestward
offshore of the coast of southern and southwestern Mexico.
* Formation chance through 48 hours...low...10 percent.
* Formation chance through 7 days...low...10 percent.

$$
Forecaster Jelsema

[Teban54]

Oof.

[cycloneye]

The 91L syndrome.

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
1100 PM PDT Fri Oct 17 2025

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

1. South of Southern Mexico (EP91):
Showers and thunderstorms associated with a broad area of low
pressure located a couple hundred miles off the coast of southern
Mexico remain limited and disorganized. Development of this system
is no longer expected.
* Formation chance through 48 hours...low...near 0 percent.
* Formation chance through 7 days...low...near 0 percent.



Forecaster Jelsema