2021 EPAC Season

[Teban54]

If you said a month ago that we have a real chance to see two EPAC hurricanes in October during a developing weak to moderate La Nina, nobody would have believed you

[Category5Kaiju]

If you said a month ago that we have a real chance to see two EPAC hurricanes in October during a developing weak to moderate La Nina, nobody would have believed you

I mean, seeing hurricanes in the EPAC in a developing La Niña year in October is not all that uncommon, for example 1998 had a Cat 3 and two Cat 1s in October.

[Yellow Evan]

12z ECMWF came in further east and stronger but you can tell that’s sheared.

[Yellow Evan]

18z GFS further west but still into Guerrero. Intensity wise, still formidable but clear sign of a displaced ULAC.

[aspen]

The EPac is about to Rickroll and flex on the Atlantic in a few days.

[Yellow Evan]

1. An area of disturbed weather is located to the south of Central
America. Environmental conditions are expected to be conducive for
gradual development of this system during the next several days,
and a tropical depression could form late this week or this weekend
while the system moves west-northwestward to northwestward near or
just south of the coast of southern Mexico.
* Formation chance through 48 hours...low...near 0 percent.
* Formation chance through 5 days...medium...50 percent.

[Ubuntwo]

0z GFS develops slower and further southwest, avoiding a quick landfall. Moderate mid level shear prevents too much deepening as with the Euro.

[Yellow Evan]

This is not going to look pretty with 25 knots of mid level shear.

[Category5Kaiju]

https://cdn.discordapp.com/attachments/733552978572869632/899877293474844692/KDyhZkIEIoTqqKAQUAgoBhYBCQCGgELATAUWY2ImmqkshoBBQCCgEsh0CijCxfkuhpg9e7YtvmCuWoHsdp999hk9ySFLyJqnikJA.png

This is not going to look pretty with 25 knots of mid level shear.

I am assuming you mean "pretty" in terms of storm look, not impacts?

[Category5Kaiju]

The EPac is about to Rickroll and flex on the Atlantic in a few days.

No. Mother Nature already did its Rickroll on all us wx enthusiasts who were expecting a busy Atlantic October and more activity across the NH.

[MHC Tracking]

Unless model predictions change drastically this will probably play out in a similar way to Pamela in terms of shear.

[cycloneye]

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
500 PM PDT Tue Oct 19 2021

For the eastern North Pacific...east of 140 degrees west longitude:

A broad area of disturbed weather located a few hundred miles south
of the coasts of Guatemala and El Salvador continues to produce
widely scattered showers and thunderstorms. Environmental
conditions are expected to be conducive for gradual development of
this system during the next several days, and a tropical depression
is likely to form by late this week or this weekend while the system
moves west-northwestward to northwestward near or just off the coast
of southern Mexico.
* Formation chance through 48 hours...low...10 percent.
* Formation chance through 5 days...high...70 percent.

$$
Forecaster Papin

[Yellow Evan]

 https://twitter.com/icyclone/status/1450634376006537219

[Teban54]

https://twitter.com/icyclone/status/1450634376006537219?s=21

Hard to put "GFS" and "excellent performance" next to each other after Pamela...

[skyline385]

https://twitter.com/icyclone/status/1450634376006537219?s=21

Hard to put "GFS" and "excellent performance" next to each other after Pamela...

Pamela was an outlier, but otherwise GFS has completely crapped over EURO in the last few seasons. Even the HWRF got Pamela completely wrong and it was the most accurate model intensity-wise per NHC post season analysis.

[Yellow Evan]

GFS favoring track into Guerrero while ECMWF has this brushing offshore. Answer is probably between the two extremes. Intensity will somewhat depend on time it has over water.

[Yellow Evan]

000
ABPZ20 KNHC 201815
TWOEP

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
1100 AM PDT Wed Oct 20 2021

For the eastern North Pacific...east of 140 degrees west longitude:

A broad area of disturbed weather is producing some disorganized
showers and a few thunderstorms within a couple of hundred miles of
the coasts of southern Mexico and Guatemala. Environmental
conditions are expected to be conducive for gradual development of
this system during the next few days, and a tropical depression is
likely to form by this weekend while the system moves slowly
west-northwestward to northwestward near or just offshore the coast
of southern Mexico.
* Formation chance through 48 hours...low...20 percent.
* Formation chance through 5 days...high...80 percent.

$$
Forecaster Reinhart

[cycloneye]

 https://twitter.com/iCyclone/status/1450893521221787655

[Ubuntwo]

18z GFS comes in weaker and slower w/ a moderate TS. Landfall location about the same.

[cycloneye]

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
500 PM PDT Wed Oct 20 2021

For the eastern North Pacific...east of 140 degrees west longitude:

A broad area of disturbed weather continues to produce disorganized
showers and a few thunderstorms within a couple of hundred miles off
the southern coast of Mexico. Environmental conditions are expected
to be conducive for gradual development of this system during the
next few days, and a tropical depression is likely to form by this
weekend while the system moves slowly west-northwestward to
northwestward near or just offshore the southern coast of Mexico.
* Formation chance through 48 hours...low...20 percent.
* Formation chance through 5 days...high...80 percent.

$$
Forecaster Papin