2017 indicators: SST's / MSLP / SAL / Steering / Instability

[TheStormExpert]

Either the models are just that bad at detecting storms further than a few days out or this season could be a snooze fest. You pick and choose.

[RL3AO]

The new version of the GFS sure seems to produce fewer now in the Atlantic and makes model watching a little less entertaining

[wxman57]

The new version of the GFS sure seems to produce fewer now in the Atlantic and makes model watching a little less entertaining

You could always just count the number of hurricanes in the latest Canadian run.

I suspect that the "on" button will be pressed in the next 7-10 days, regardless of what the models are indicating.

[Cpv17]

The old GFS seemed to be too aggressive and this one seems to be too conservative so far.

[Steve]

The new version of the GFS sure seems to produce fewer now in the Atlantic and makes model watching a little less entertaining

You could always just count the number of hurricanes in the latest Canadian run.

I suspect that the "on" button will be pressed in the next 7-10 days, regardless of what the models are indicating.

The resolution I have access to only puts like a split system recurving not far off the US Coast. JMA has a circulation off the NW tip of the Yucatan by 192 hours. EC has a low coming in South of Brownsville between 216 and 240 hours (9/10 days). Those two are fairly close in solution.

[Kingarabian]

According to the EPS, 15 days out and background forcing is still an issue for the Atlantic:

[RL3AO]

According to the EPS, 15 days out and background forcing is still an issue for the Atlantic:

Assuming the 15 day model forecast is correct, of course.

[gatorcane]

Either the models are just that bad at detecting storms further than a few days out or this season could be a snooze fest. You pick and choose.

Just because the calendar says "Aug 1st" doesn't mean the models will start showing storms plus the GFS is just as conservative as the ECMWF it seems now with MDR development. I am confident the models will start lighting up in the next week or two but don't be surprised if they go from showing nothing to something in a single run even in the medium range. A few interesting indicators - 1) the models are showing the EPAC slowing down over the next couple of weeks (usually that translates to Atlantic development) and 2) the models have been on and off again with some MDR development indicating conditions are gradually becoming more favorable 3) The SAL across the deep MDR seems to be thinning lately especially near the coast of Africa. Let's also not forget areas outside of the MDR (BoC), decaying frontal systems (e.g. Emily, etc that could also spawn development.

[Kingarabian]

According to the EPS, 15 days out and background forcing is still an issue for the Atlantic:

Assuming the 15 day model forecast is correct, of course.

Of course. Although it's supposed to be a La Nina pattern which would technically favor Atlantic development (Rising over the MC and the WPac/Sinking in the CPac), pre-dominant rising air is taking place over the EPac thus displacing the sinking air towards the Atlantic (Walker Cell??? Nino 1+2 not cool enough? I don't know). So it appears to be that atmosphere is resembling a La Nina and an El Nino.

[TheStormExpert]

The new version of the GFS sure seems to produce fewer now in the Atlantic and makes model watching a little less entertaining

You could always just count the number of hurricanes in the latest Canadian run.

I suspect that the "on" button will be pressed in the next 7-10 days, regardless of what the models are indicating.

Always enjoy your insight. What are your thoughts or predictions for the rest of the season? Compared to last year how do you think it'll be?

[tolakram]

I remember the GFS showing nothing for 16 days and then the next run it had Matthew.

No, the answer is no one remembers. Apparently we expect the models to show storms 5 to 10 days out all the time, with reliability, because that's the way it's always been. Back in the day and all that.

[Alyono]

Niño 1-2 has warmed somewhat recently. May be why we have the blasting shear in the Caribbean, as well as the downward forcing. Upward branch of the Walker Circulation may be in the EPAC

[gatorcane]

I remember the GFS showing nothing for 16 days and then the next run it had Matthew.

No, the answer is no one remembers. Apparently we expect the models to show storms 5 to 10 days out all the time, with reliability, because that's the way it's always been. Back in the day and all that.

Another example is Joaquin from 2015. If you go back to the Storm2K thread on that, it started out with basically little to no chance of development where models had basically nothing in the medium-range (like only 5-6 days out). Then suddenly the UKMET/ECMWF models were the first models which showed something big approaching the Bahamas and the rest is history.

[WeatherEmperor]

Niño 1-2 has warmed somewhat recently. May be why we have the blasting shear in the Caribbean, as well as the downward forcing. Upward branch of the Walker Circulation may be in the EPAC

Overall shear in the Caribbean looks below normal for this time of year. Perhaps this graph does not tell the whole story?


Sent from my iPhone 7 using Tapatalk

[Kingarabian]

Niño 1-2 has warmed somewhat recently. May be why we have the blasting shear in the Caribbean, as well as the downward forcing. Upward branch of the Walker Circulation may be in the EPAC

Atmosphere seemingly playing tug of war between La Nina and El Nino forcing. That's why Ntxw is on the money in regards to that if the ENSO forecast is complicated then making a forecast for anything else will be just as complicated.

[Kingarabian]

Niño 1-2 has warmed somewhat recently. May be why we have the blasting shear in the Caribbean, as well as the downward forcing. Upward branch of the Walker Circulation may be in the EPAC

[img]https://uploads.tapatalk-cdn.com/20170801/713bbf96b7675b55995aa3c724ae9c2b.gif[img]

Overall shear in the Caribbean looks below normal for this time of year. Perhaps this graph does not tell the whole story?


Sent from my iPhone 7 using Tapatalk

I think it can be misleading. North of the islands, shear is low/normal. In the east and western Caribbean it's running high. I think I posted an image on the previous page that shows how favorable shear in the GOM and Caribbean looks like.

[Ntxw]

Niño 1-2 has warmed somewhat recently. May be why we have the blasting shear in the Caribbean, as well as the downward forcing. Upward branch of the Walker Circulation may be in the EPAC

https://uploads.tapatalk-cdn.com/201708 ... ae9c2b.gif

Overall shear in the Caribbean looks below normal for this time of year. Perhaps this graph does not tell the whole story?

Past month or so has been above normal in the Carib. And you can see it on the daily shear maps it has been persistent. You need periods of little to no shear also, even weak shear is still shear. MDR east of Carib has seen very low shear

 https://twitter.com/philklotzbach/status/891807885939941378

[otowntiger]

The old GFS seemed to be too aggressive and this one seems to be too conservative so far.

Agreed that it was too aggressive as so many forecast storms didn't come to fruition. But it is kinda hard to determine yet if it is too conservative when so far it hasn't been proven wrong. One can only make that call when/if we start seeing storms develop more than it has forecast.

[TheStormExpert]

What would this mean for the remainder of the Atlantic season?

 https://twitter.com/mjventrice/status/892411466107805696

[tarheelprogrammer]

What would this mean for the remainder of the Atlantic season?

 https://twitter.com/mjventrice/status/892411466107805696

It should mean bye bye to an active season. It could also mean bye bye to a normal season. I am not 100% sure though. Just thought I would give my dumb opinion.