2021 EPAC Season

[Kingarabian]

This will help the PMM a little bit. Help warm up the lacking 18N-20N SST's.

[Yellow Evan]

Slightly off topic but:

 https://twitter.com/drmetwatch/status/1430183746020519944

[Yellow Evan]

0z ECMWF still having a storm close to MX.

[Yellow Evan]

12z GFS had a fun fantasy run, with a hurricane moving all the way up the Gulf of California. Won't happen though.

[Kingarabian]

https://i.imgur.com/Jb97s26.png

0z ECMWF still having a storm close to MX.

Yeah some waning support from the EPS for this system. I think we'll be entering the long awaited lull of EPAC activity soon with the Atlantic going off.

[Kingarabian]

Some possible areas of interest on the 12z Euro:


Minimal EPS support though. Need something cranking soon to get ACE back up to Climo. We're about to fall below climo despite the high number of systems and decent amount of hurricanes.

[Yellow Evan]

Next window for development isn’t really until September 20 or so. Not falling for anything before then.

Btw -PDO is deepening though horseshoe remains warm.

[Kingarabian]

12z Euro continues with what appears to be a legit AOI in about a week:



Has 40-45% EPS support in 10 days.

[Kingarabian]

12z GFS back to the EPAC bias. However we should see at least one named storm.

[Yellow Evan]

0z ECMWF more realistically has nada.

[Kingarabian]

12z Euro now showing two robust disturbances with good EPS support for both:


There will be a CCKW moving into the EPAC from September 6 -> 13.

[Yellow Evan]

45 day EPS. I guess there’s a small window for something around September 10 but not as aggressive as the GFS suggests. Late September/early October remains the next window for significant activity.

[AlphaToOmega]

ZCZC MIATWOEP ALL
TTAA00 KNHC DDHHMM

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
500 PM PDT Thu Sep 2 2021

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

1. An area of low pressure is forecast to form early next week off the
southwestern coast of Mexico. Environmental conditions are expected
to be conducive for some gradual development of the system
thereafter as it moves west-northwestward away from southwestern
Mexico.
* Formation chance through 48 hours...low...near 0 percent.
* Formation chance through 5 days...low...20 percent.

Forecaster Brown

[Kingarabian]

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
500 PM PDT Fri Sep 3 2021

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

1. An area of low pressure is forecast to form early next week off the
southwestern coast of Mexico. Environmental conditions are expected
to be conducive for gradual development thereafter, and the system
could become a tropical depression around midweek as it moves
west-northwestward or northwestward.
* Formation chance through 48 hours...low...near 0 percent.
* Formation chance through 5 days...medium...40 percent.

Forecaster Brown

[Yellow Evan]

12z ECMWF doesn’t show much and it’s probably right.

[Kingarabian]

NEW TROPICAL CYCLONE FORECAST TO DEVELOP AFTER 60 HOURS
FORECAST POSITION AT T+ 60 : 12.3N 121.2W

LEAD CENTRAL MAXIMUM WIND
VERIFYING TIME TIME POSITION PRESSURE (MB) SPEED (KNOTS)
-------------- ---- -------- ------------- -------------
1200UTC 06.09.2021 60 12.3N 121.2W 1008 27
0000UTC 07.09.2021 72 13.4N 120.9W 1007 28
1200UTC 07.09.2021 84 14.6N 120.2W 1009 20
0000UTC 08.09.2021 96 14.7N 119.3W 1009 25
1200UTC 08.09.2021 108 CEASED TRACKING

NEW TROPICAL CYCLONE FORECAST TO DEVELOP AFTER 90 HOURS
FORECAST POSITION AT T+ 90 : 18.8N 109.1W

LEAD CENTRAL MAXIMUM WIND
VERIFYING TIME TIME POSITION PRESSURE (MB) SPEED (KNOTS)
-------------- ---- -------- ------------- -------------
0000UTC 08.09.2021 96 18.5N 109.6W 1004 29
1200UTC 08.09.2021 108 18.6N 110.6W 1002 32
0000UTC 09.09.2021 120 19.2N 110.7W 999 34
1200UTC 09.09.2021 132 19.9N 112.0W 998 36
0000UTC 10.09.2021 144 20.9N 113.0W 998 34

NEW TROPICAL CYCLONE FORECAST TO DEVELOP AFTER 102 HOURS
FORECAST POSITION AT T+102 : 13.2N 147.2W

LEAD CENTRAL MAXIMUM WIND
VERIFYING TIME TIME POSITION PRESSURE (MB) SPEED (KNOTS)
-------------- ---- -------- ------------- -------------
1200UTC 08.09.2021 108 13.4N 147.7W 1009 23
0000UTC 09.09.2021 120 14.1N 148.4W 1009 27
1200UTC 09.09.2021 132 14.8N 149.5W 1010 24
0000UTC 10.09.2021 144 15.5N 150.4W 1010 21

[Yellow Evan]

Not trusting the Br*ts. 60 hours seems to soon for genesis though decent agreement with that and GFS for track.

[AlphaToOmega]

12z ECMWF doesn’t show much and it’s probably right.

Development is possible. The ECMWF shows a small short-lived rising air cell over the east Pacific from September 6 to 12. Something could form from that.

[Yellow Evan]

0z ECMWF actually has this and something south of Guerrero.

[Kingarabian]

18z GFS trying again with Arizona: