2017 Global Model Runs Discussion (Out to day 16)

[tolakram]

These GFS and ECMWF model verifications are freely available from Weatherbell.

http://models.weatherbell.com/verification.php

Both models have been having serious (relative to their normal performance) issues at 5 days.


At 7 days both are worse than normal, but note how the GFS occasionally does a tad better than the euro.

[RL3AO]

To be fair to the models, this doesn't look like the easiest pattern to predict right now either!

[OuterBanker]

These GFS and ECMWF model verifications are freely available from Weatherbell.

http://models.weatherbell.com/verification.php

Both models have been having serious (relative to their normal performance) issues at 5 days.


At 7 days both are worse than normal, but note how the GFS occasionally does a tad better than the euro.

Thanks for that post tolakram. How interesting, the Euro is constantly better than the GFS . Of equal interest is that both are much worse than last year (note 2016 stats in the upper right of the main chart). Is their any reason why?

[OuterBanker]

My bad, after reading that chart I realized that was the past 365 accuracy. I guess the question is why is it so bad lately?

[RL3AO]

My bad, after reading that chart I realized that was the past 365 accuracy. I guess the question is why is it so bad lately?

Model accuracy drops in the NH during summer. I'm guessing the high latitude blocking over northern Canada recently is making it worse than usual in the summer. That's really just a guess. I have no data to back that up.

[Digital-TC-Chaser]

[Digital-TC-Chaser]

ZCZC MIATWOAT ALL
TTAA00 KNHC DDHHMM

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
800 AM EDT Thu Jun 15 2017

For the North Atlantic...Caribbean Sea and the Gulf of Mexico:

1. A tropical wave located several hundred miles south-southwest of
the Cabo Verde Islands is producing disorganized showers and
thunderstorms. Some gradual development of this system is possible
during the next few days while the wave moves westward near 20 mph
over the tropical Atlantic.
* Formation chance through 48 hours...low...10 percent.
* Formation chance through 5 days...low...20 percent

[ROCK]

Kudos to the CMC for sniffing this out way before any other global. Even though its trashy right now it will come around. The European should be the one to follow as of now..JMO

12z GFS is trash btw

[Digital-TC-Chaser]

RE: the gulf storm. looping track over land and back into the gulf to re ramp up plausible?

[tarheelprogrammer]

GFS now hinting at development of the wave behind 92L. WOW!

[Yellow Evan]

GFS now hinting at development of the wave behind 92L. WOW!

Also at a little higher latitude so more likely to run into shear/dry air problems.

[tarheelprogrammer]

GFS now hinting at development of the wave behind 92L. WOW!

Also at a little higher latitude so more likely to run into shear/dry air problems.

Very true, but it is still impressive none the less.

[Hurricaneman]

GFS now hinting at development of the wave behind 92L. WOW!

Also at a little higher latitude so more likely to run into shear/dry air problems.

Very true, but it is still impressive none the less.

Well if you look at the CFSv2 monthlies it doesn't look like the development train isnt going to stop so that may be an area to watch from now to October but that's real interesting what the GFS is showing a train of development in the MDR this early in the season

[Yellow Evan]

Also at a little higher latitude so more likely to run into shear/dry air problems.

Very true, but it is still impressive none the less.

Well if you look at the CFSv2 monthlies it doesn't look like the development train isnt going to stop so that may be an area to watch from now to October but that's real interesting what the GFS is showing a train of development in the MDR this early in the season

CFS monthlies have above average shear in August and September, but above average rainfall throughout the season. I don't trust the CFS monthly shear product much though.

[RL3AO]

There was a strong Kelvin wave passing though the Eastern Atlantic and Africa which can amplify African Easterly Waves. I'm curious to see if the wave train continues now that we're back to the usual June atmosphere.

[TheAustinMan]

If you follow models on TropicalTidbits I made a chart listing out the times when the models available begin to update. This is an approximation of those times, and as a result they may vary from run to run.

Since all models there have 12z runs, those are indicated on the chart, but the models should have the same offsets for 00z, 06z, and 18z runs.

[Siker]

12z Euro actually has another weak Cape Verde storm developing at the end of its run.

[Hammy]

12z Euro actually has another weak Cape Verde storm developing at the end of its run.

What would the implications be should we see two CV storms before the second week of July?

[Hurricaneman]

12z Euro actually has another weak Cape Verde storm developing at the end of its run.

What would the implications be should we see two CV storms before the second week of July?

Probably quite a bit above normal season but don't know by how much

[Kingarabian]

Doubt any waves rolling off Africa will be able to get going next week since the MDR will start to feel the suppressed phase of the MJO.