2021 EPAC Season

[Kingarabian]

GFS and CMC are mostly quiet. 12z Euro has no serious development but does have some robust disturbances in the 7-10 day range.


Also like the past 6 EPS runs, there's a strong signal for a long EPAC tracker in the 13-16 day range.

[Yellow Evan]

If you want tropical activity in the next week, track Elsa. Base start in this basin is hostile rn, although I expect this to change in the third week of the month.

[Kingarabian]

If you want tropical activity in the next week, track Elsa. Base start in this basin is hostile rn, although I expect this to change in the third week of the month.

Yeah definitely monitoring Elsa. But the ensembles are showing activity in 10 days so we'll see.

[Kingarabian]

00z Euro has development in less than 7 days:


00z CMC and Euro also have something in 10 days:

[Kingarabian]

12z EPS continue to strongly suggest a couple of systems in the 2nd week of July, with the time frame coming in.

[Kingarabian]

EPS continues in showing two systems, with the first starting around July 10-13:


CMC has been consistent with it:

[Kingarabian]

GFS is still not interested. 00z CMC continues with twin systems. 00z Euro also has legit twins but weaker systems. However the EPS remains bullish on both.

[Kingarabian]

The GFS is now on board with potentially multiple long trackers, but only keeps one strong. It looks to be three potential systems in total though.

Should see a circle by Thursday or Friday. CMC has development in 7 days now:

12z CMC two systems by hour 240, favoring the first two systems:



12z Euro:

Still shows two weak areas but they're evidently there and strong on the EPS

12z GFS:

[Kingarabian]

Per the latest EPS, weak CCKW's 1 and 2 will combine to spark EPAC activity. Looking ahead, a well defined MJO pulse will begin moving into the CPAC by July20ish.

[Yellow Evan]

Don't extrapolate past July 19 just because the MJO has been so erratic recently.

[Kingarabian]

:uarrow: Don't extrapolate past July 19 just because the MJO has been so erratic recently.

That's because its been in the circle. I think we can comfortably call for a Pacific MJO passage since the signal is strong this far out on the reliable models. This will be the last big MJO till the fall I believe.

[Yellow Evan]

12z GFS more realistically has nothing for the entire 16 day period.

[Kingarabian]

12z CMC favoring the first system:
144 hours:


240 hours:


12z Euro favoring the 2nd system but the EPS likes the first system better:


12z EPS really favoring the first system though.

[Yellow Evan]

-PDO configuration seems to have returned after briefly weakening, and the seasonal -VP anomalies have not arrived.

[Kingarabian]

[url]https://cdn.discordapp.com/attachments/733552978572869632/861695589770854410/compday.png[url]

[url]https://cdn.discordapp.com/attachments/733552978572869632/861696491945197578/5pxSsG6d8Q.png[url]
[url]https://cdn.discordapp.com/attachments/733552978572869632/861696140784828416/Screen_Shot_2021-07-05_at_3.52.46_PM.png[url]

-PDO configuration seems to have returned after briefly weakening, and the seasonal -VP anomalies have not arrived.

Looks pretty cool when we subtract from the global mean. But so does every other basin. Regular daily anomalies and the 15 day change graphics don't look too bad.

[Kingarabian]

12z EPS:


And it's been like this for at least 10 runs in a row.

[aspen]

[url]https://cdn.discordapp.com/attachments/733552978572869632/861695589770854410/compday.png[url]

[url]https://cdn.discordapp.com/attachments/733552978572869632/861696491945197578/5pxSsG6d8Q.png[url]
[url]https://cdn.discordapp.com/attachments/733552978572869632/861696140784828416/Screen_Shot_2021-07-05_at_3.52.46_PM.png[url]

-PDO configuration seems to have returned after briefly weakening, and the seasonal -VP anomalies have not arrived.

Looks pretty cool when we subtract from the global mean. But so does every other basin. Regular daily anomalies and the 15 day change graphics don't look too bad.
https://i.imgur.com/h8UqtkF.png
https://i.imgur.com/b6akiim.png

Off topic but the Atlantic looks solid. The MDR is nowhere near as cool as on the CDAS map, and the Caribbean is quite warmer than average. If the position of the ITCZ allows for lower tracking storms than in previous years, and if those Caribbean SST anomalies remain above-average in August and September, then this year might mark the return of Caribbean Cruising Majors.

[Yellow Evan]

[url]https://cdn.discordapp.com/attachments/733552978572869632/861695589770854410/compday.png[url]

[url]https://cdn.discordapp.com/attachments/733552978572869632/861696491945197578/5pxSsG6d8Q.png[url]
[url]https://cdn.discordapp.com/attachments/733552978572869632/861696140784828416/Screen_Shot_2021-07-05_at_3.52.46_PM.png[url]

-PDO configuration seems to have returned after briefly weakening, and the seasonal -VP anomalies have not arrived.

Looks pretty cool when we subtract from the global mean. But so does every other basin. Regular daily anomalies and the 15 day change graphics don't look too bad.
https://i.imgur.com/h8UqtkF.png
https://i.imgur.com/b6akiim.png

Off topic but the Atlantic looks solid. The MDR is nowhere near as cool as on the CDAS map, and the Caribbean is quite warmer than average. If the position of the ITCZ allows for lower tracking storms than in previous years, and if those Caribbean SST anomalies remain above-average in August and September, then this year might mark the return of Caribbean Cruising Majors.

If the -VP does not return like it typically does in ASO, that’d be major boom to the Caribbean. A flip to +PMM (common at the end of La Niña events) would help.

[Yellow Evan]

[url]https://cdn.discordapp.com/attachments/733552978572869632/861695589770854410/compday.png[url]

[url]https://cdn.discordapp.com/attachments/733552978572869632/861696491945197578/5pxSsG6d8Q.png[url]
[url]https://cdn.discordapp.com/attachments/733552978572869632/861696140784828416/Screen_Shot_2021-07-05_at_3.52.46_PM.png[url]

-PDO configuration seems to have returned after briefly weakening, and the seasonal -VP anomalies have not arrived.

Looks pretty cool when we subtract from the global mean. But so does every other basin. Regular daily anomalies and the 15 day change graphics don't look too bad.
https://i.imgur.com/h8UqtkF.png
https://i.imgur.com/b6akiim.png

Yes but only due to AGW. Long term the fastest way for a strong +PDO to return is for the warm blob towards the Gulf of Alaska to migrate eastward towards the west coast of California. I could see this happening by the end of the year but it’s also not particularly likely.

[Yellow Evan]

12z EPS:
https://i.imgur.com/W8iSslw.png

And it's been like this for at least 10 runs in a row.

I actually do think there’s a good chance this will be something given the broad support. Probably not strong however.