2021 EPAC Season

[Yellow Evan]

0z ECMWF actually tried to develop both. Probably the best chance at keeping the basin respectable.

[cycloneye]

An area of low pressure is forecast to develop by midweek a few
hundred miles south or southeast of the Gulf of Tehuantepec.
Thereafter, some gradual development is possible through late this
week while the system moves generally west-northwestward at 10 to 15
mph, remaining a couple of hundred miles offshore of the coast of
southern Mexico.
* Formation chance through 48 hours...low...near 0 percent.
* Formation chance through 5 days...medium...40 percent.

[Yellow Evan]

Next window after the upcoming activity seems to be around August 10.

[Yellow Evan]

0z GFS now showing the 0/30, and two disturbances and a potent hurricane behind one of the disturbances. Given the favorable (overly so) -VP it shows this makes sense.

'

[Yellow Evan]

000
ABPZ20 KNHC 260549
TWOEP

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
1100 PM PDT Sun Jul 25 2021

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

A well-defined low pressure system located about 1100 miles
east-southeast of the Hawaiian Islands continues to move westward at
about 15 mph. Shower and thunderstorm activity remains disorganized,
and environmental conditions are gradually becoming less conducive
for additional development to occur. However, any increase in the
organization of the shower activity would result in the formation of
a tropical depression on Monday. The low is forecast to move into
the Central Pacific basin by late Monday morning, and by Tuesday
conditions are expected to become unfavorable for further
development.
* Formation chance through 48 hours...medium...60 percent.
* Formation chance through 5 days...medium...60 percent.

An area of low pressure is forecast to develop by midweek a few
hundred miles south or southeast of the Gulf of Tehuantepec.
Thereafter, some gradual development is possible through late this
week while the system moves generally west-northwestward at 10 to 15
mph, remaining a couple of hundred miles offshore of the coast of
southern Mexico.
* Formation chance through 48 hours...low...near 0 percent.
* Formation chance through 5 days...medium...40 percent.

$$
Forecaster Stewart

[cycloneye]

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
1100 AM PDT Mon Jul 26 2021

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

1. A small but well-defined area of low pressure located about 700
miles south-southwest of the southern tip of the Baja California
peninsula is producing limited shower and thunderstorm activity.
Some gradual development of this system is possible over the next
several days as it moves westward at around 10 mph.
* Formation chance through 48 hours...low...10 percent.
* Formation chance through 5 days...low...20 percent.

2. An area of low pressure is forecast to develop in a few days several
hundred miles south of the Gulf of Tehuantepec. Environmental
conditions appear conducive for some gradual development thereafter,
and a tropical depression could form late this week or over the
weekend while the system moves west-northwestward at around 15 mph,
remaining several hundred miles offshore of the coast of southern
Mexico.
* Formation chance through 48 hours...low...near 0 percent.
* Formation chance through 5 days...medium...40 percent.

Forecaster Reinhart/Pasch

[cycloneye]

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
500 PM PDT Mon Jul 26 2021

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

1. A small but well-defined area of low pressure located more than 700
miles south-southwest of the southern tip of the Baja California
peninsula continues to produce a small area of shower and
thunderstorm activity near its center. Some gradual development of
this system is possible over the next several days as it moves
westward at around 10 mph.
* Formation chance through 48 hours...low...20 percent.
* Formation chance through 5 days...low...30 percent.

2. An area of low pressure is forecast to develop in a few days several
hundred miles south of the Gulf of Tehuantepec. Environmental
conditions appear conducive for some gradual development thereafter,
and a tropical depression could form late this week or over the
weekend while the system moves west-northwestward at around 15 mph,
staying several hundred miles offshore of the coast of southern
Mexico.
* Formation chance through 48 hours...low...near 0 percent.
* Formation chance through 5 days...medium...40 percent.

Forecaster Papin/Brown

[cycloneye]

Invest 99E is up

[aspen]

GFS is now only forecasting a strong TS from that 0/40 AOI. Maybe it could over-perform, but since it’s a cool ENSO year…probably not.

[Yellow Evan]

GFS is now only forecasting a strong TS from that 0/40 AOI. Maybe it could over-perform, but since it’s a cool ENSO year…probably not.

Also keeps pushing the time frame back which given the VP setup isn't surprising. A two storm July is looking pretty likely now.

[Yellow Evan]

That signal is enough to convince me August should be formidable. Although weak the -VP is there.

[Yellow Evan]

18z GFS quite bullish in the medium and long range. Ofc it's also pretending we are stuck in the 80s and there's no ASW.

[Kingarabian]

Best bet for our next hurricane/major hurricane will be the 0/40. Models and ensembles show it following a track that's similar to Felicia.

[Yellow Evan]

0z ECMWF seems to favor an area between 99E and the 0/40. Given the lack of consistency, even if this sort of pattern isn't unusual for this time of the year especially with sinking air on the east side of the basin (next few days not withstanding), of the model runs, I'm not particularly enthusiastic. Most likely we'll see a bunch of disturbances that don't become anything strong.

[Yellow Evan]

12z GFs no longer has the 0/40.

[cycloneye]

An area of low pressure is expected to develop later this week
several hundred miles offshore of the southern coast of Mexico.
Environmental conditions are forecast to be favorable for some
gradual development thereafter, and a tropical depression could form
this weekend while the system moves westward or west-northwestward
at around 10 to 15 mph.
* Formation chance through 48 hours...low...near 0 percent.
* Formation chance through 5 days...medium...40 percent.

[Yellow Evan]

FWIW GFS not seeming to show it’s typical 80s style American standing wave pattern. Ofc it’s not showing an African standing wave pattern either so continue to disregard.

[Kingarabian]

12z Euro keying in on this track for the 0/40:

[cycloneye]

An area of low pressure is expected to develop later this week
several hundred miles offshore of the southwestern coast of Mexico.
Environmental conditions are forecast to be favorable for some
gradual development thereafter, and a tropical depression could form
this weekend while the system moves westward or west-northwestward
at around 10 to 15 mph.
* Formation chance through 48 hours...low...near 0 percent.
* Formation chance through 5 days...medium...40 percent.

[Kingarabian]

CMC and GFS have been trying to spin up some CPAC homebrew that eventually moves into the WPAC.