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Tropical Global Model Runs Discussion 2017

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12Z Euro is very interesting. It shows a weak low in GOMEX next week and it moves into the Carolinas which will give them good heavy rain if plays out!! The end of the run shows another developing weak low pressure in GOMEX that could be moving into the FL panhandle!!
 
The 12Z EPS suggests that the 12Z Euro operational is somewhat of an outlier with the EPS mean having the E US ridging holding on much longer than the op and similar to both its 0Z run as well as the 12Z GEFS and 12Z GEPS means. As a result, the 12Z EPS actually has a good bit more TC activity than its 0Z run for FL during the 10/7-10 interval, similar to but not as active as the very active 12Z GEFS there.

The 12Z GEPS also has some activity in FL and more than its own 0Z run.

Conclusion: Despite what the 12Z Euro showed, FL and nearby areas do still appear to be at an appreciable risk around 10/7-10 for a W Caribbean originating TC to hit them from below based on all 3 major 12Z ensemble runs.

I'm quoting the above post from 3 days ago (Thu PM) because it was suggesting a heightened risk to FL 10/7-10 from below, including all 3 Thu 12Z ensembles. Since then, the ensembles as a whole had suggested a lessened threat with the Fri and Sat runs, overall, especially the EPS. However, today's two EPS runs are going gangbusters again as far as number of members with a TC crossing FL between late 10/7 and 10/10 while moving either NE or NNE. Note that this is the same timeframe on EPS runs 3 days later as opposed to there being time slippage.

With the EPS being the best guidance overall, the origin showing to be the western Caribbean, the insanely high western Caribbean heat content, and the current cold neutral ENSO increasing the risk for any H hit to W FL in Oct being major, this needs to be monitored very carefully regardless of many runs of various models showing only a TS hit. Also, even just a TS hit would be quite problematic for FL after what Irma left behind, especially if wet.
 
I'm quoting the above post from 3 days ago (Thu PM) because it was suggesting a heightened risk to FL 10/7-10 from below, including all 3 Thu 12Z ensembles. Since then, the ensembles as a whole had suggested a lessened threat with the Fri and Sat runs, overall, especially the EPS. However, today's two EPS runs are going gangbusters again as far as number of members with a TC crossing FL between late 10/7 and 10/10 while moving either NE or NNE. Note that this is the same timeframe on EPS runs 3 days later as opposed to there being time slippage.

With the EPS being the best guidance overall, the origin showing to be the western Caribbean, the insanely high western Caribbean heat content, and the current cold neutral ENSO increasing the risk for any H hit to W FL in Oct being major, this needs to be monitored very carefully regardless of many runs of various models showing only a TS hit. Also, even just a TS hit would be quite problematic for FL after what Irma left behind, especially if wet.
Wet is an issue - trees are not stable. Any wind would be devastating.
Larry - can you post whatever you're looking at, or if proprietary send me a PM?
Thanks!
Phil
 
Wet is an issue - trees are not stable. Any wind would be devastating.
Larry - can you post whatever you're looking at, or if proprietary send me a PM?
Thanks!
Phil

I'm not just thinking of the trees falling over more easily due to wet soil. I'm also thinking about potential flooding as the last thing most of FL needs right now is rain after the major deluge from Irma plus heavy rains preceding Irma.
 
So, here's the deal with the GFS as I see it. The last 5 GFS runs (including the brand new 18Z) as well as today's 12Z CMC have been developing a separate disturbance near west-central Cuba late 10/4 to early 10/5 and then moving it westward well into the Gulf. What this has served to do is protect FL from a potential big hit from below from a western Caribbean genesis soon afterward due to spreading out the available energy and thus not allowing the w Caribbean energy to do much, even when that separate disturbance is weak. But note that no Euro run has yet to do something similar and, as a consequence, its last 3 runs and its 2 ensemble means of today have had a strong signal in the NE Gulf/FL for 10/7-10 unlike those GFS runs, the last few GEFS runs, and the 12Z CMC.

So, as I see it, the formation or the lack thereof of a separate earlier disturbance near west central Cuba 10/4-5 will go a long ways to determining whether or not there is a real threat of a significant TC to FL 10/7-10. If you don't want that threat, I'd root very hard for this earlier disturbance near Cuba to develop as I'm convinced it would protect FL from anything big around 10/7-10.

Edit: The 12Z Euro 144 hour position is supported by the 12Z Ukmet's and 12Z NAVGEM's 144 hour position. However, the 12Z JMA is not in support.
 
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So, here's the deal with the GFS as I see it. The last 5 GFS runs (including the brand new 18Z) as well as today's 12Z CMC have been developing a separate disturbance near west-central Cuba late 10/4 to early 10/5 and then moving it westward well into the Gulf. What this has served to do is protect FL from a potential big hit from below from a western Caribbean genesis soon afterward due to spreading out the available energy and thus not allowing the w Caribbean energy to do much, even when that separate disturbance is weak. But note that no Euro run has yet to do something similar and, as a consequence, its last 3 runs and its 2 ensemble means of today have had a strong signal in the NE Gulf/FL for 10/7-10 unlike those GFS runs, the last few GEFS runs, and the 12Z CMC.

So, as I see it, the formation or the lack thereof of a separate earlier disturbance near west central Cuba 10/4-5 will go a long ways to determining whether or not there is a real threat of a significant TC to FL 10/7-10. If you don't want that threat, I'd root very hard for this earlier disturbance near Cuba to develop as I'm convinced it would protect FL from anything big around 10/7-10.
:cool: :p:D;)
 
Could we all agree the Southeast will get some much-needed rain from moisture moving out the gulf next weekend??
 
the blank TWO didnt last long

An elongated surface trough of low pressure interacting with an
upper-level low is producing widespread cloudiness and scattered
showers across much of the northwestern Caribbean Sea, the Yucatan
peninsula, Belize, Honduras, and Guatemala. Although surface
pressures are unusually low across the region, strong upper-level
winds and the large disturbance's proximity to land should prevent
any significant organization for the next few days. However,
environmental conditions could become a little more favorable for
the development of a low pressure system by the end of the week
across the northwestern Caribbean Sea or the southern Gulf of Mexico
while the system moves little or drifts northward.
* Formation chance through 48 hours...low...near 0 percent.
* Formation chance through 5 days...low...20 percent.

$$
 
Somewhat more threatening trends at 0Z so far for FL early next week from the potential W Caribbean system:

1. CMC: It isn't that it is such a good model. But its change from 12Z to 0Z confirms my suspicions:

Note that at 12Z there was the development near Cuba on 10/5 of a disturbance in advance of the potential W. Caribbean genesis. I was earlier saying that I feel that that earlier development there would likely protect FL from a direct hit early next week from any W. Caribbean genesis. At 12Z, FL was safe. However, at 0Z, there was a much weaker (almost nonexistent) 10/5 Cuban development. What happens? W FL gets hit by a strong TC. Coincidence? I don't think so.

2. GFS: Check out the last four GFS runs for the map effective 12Z on 10/5 (84 hour map on the 0Z), when that Cuban disturbance (the one that I think would protect FL from a potential big hit from the W. Caribbean) develops. Anyone notice the trend of the last 3 GFS runs? It has been forming further ESE each time and also has been trending weaker. The 500 mb weakness associated with it at the time of formation is also trending westward. Notice that the 0Z GFS doesn't even get this into the Gulf as it goes N over FL vs the prior 3 runs getting it well west into it. So, obviously this feature is far from set in stone. What I'm thinking is that this Cuban feature will either trend even more east in future GFS runs and/or it will just stop appearing/be more like recent Euro runs. This is considering the trend and also that the Euro is a better model vs the GFS, which likes to develop too many features. Assuming this happens on future GFS runs, I believe that the W Caribbean development will get strong again on those GFS runs as it then would have no competition for energy.
 
NOLA hit on the GFS, CMC is a little east hitting Mississippi. We may have a Gulf storm on our hands soon. I fear that if one develops down in the hot bed near the Yucatan and Cuba, we will be dealing with a big hurricane, again. I fear that it could become another big storm, but hope it is only a weak TS.
 
NOLA hit on the GFS, CMC is a little east hitting Mississippi. We may have a Gulf storm on our hands soon. I fear that if one develops down in the hot bed near the Yucatan and Cuba, we will be dealing with a big hurricane, again. I fear that it could become another big storm, but hope it is only a weak TS.
Small Minimal Hurricane per 12z GFS and 12Z CMC
 
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