2017 Global Model Runs Discussion (Out to day 16)

[psyclone]

At this point we're no closer to development today than we were a week ago. The models keep spitting out intermittent long term development that doesn't happen or keeps getting pushed out. While there's still plenty of time left, the past week has been spent running out the clock. that's the best we can hope for. Hopefully it continues.

[gatorcane]

00Z NASA model 168 hours:

[CourierPR]

At this point we're no closer to development today than we were a week ago. The models keep spitting out intermittent long term development that doesn't happen or keeps getting pushed out. While there's still plenty of time left, the past week has been spent running out the clock. that's the best we can hope for. Hopefully it continues.

In his Saturday Summary on weather bell.com, Met. Joe Bastardi was highlighting probability of development during first ten days of October according to pattern recognition.

[otowntiger]

The one thing fairly consistent in all the models is that nothing of real significance will form within the next couple of weeks. CMC is the one minor exception, with a TS/weak Cat1 sitting around the middle Gulf.the next run could very well have it go away. The first half of October could very well be quiet, will have to see what happens later in the month but the longer we go the less the chances of any CONUS impacts.

[blp]

The one thing fairly consistent in all the models is that nothing of real significance will form within the next couple of weeks. CMC is the one minor exception, with a TS/weak Cat1 sitting around the middle Gulf.the next run could very well have it go away. The first half of October could very well be quiet, will have to see what happens later in the month but the longer we go the less the chances of any CONUS impacts.

We know that intensity forecasting is tricky and add to the mix the incredible fuel you have in that region. The problem IMO is the models are giving the EPAC way to much credit for development of multiple systems and vorticities which is causing the consolidation issues in NW Carribean area and why it finally consoldates in the EGOM. The Euro has starting to indicate last few runs the EPAC development might be overdone and the energy is shifting toward the NW Carribean. If this continues I expect consolidation sooner and a much stronger system because the very favorable TCHP.

[psyclone]

At this point we're no closer to development today than we were a week ago. The models keep spitting out intermittent long term development that doesn't happen or keeps getting pushed out. While there's still plenty of time left, the past week has been spent running out the clock. that's the best we can hope for. Hopefully it continues.

In his Saturday Summary on weather bell.com, Met. Joe Bastardi was highlighting probability of development during first ten days of October according to pattern recognition.

I think development is eventually likely but each day without it is a victory. Harvey went from nothing to a category 4 in 2 days so to suggest that we're off the hook based on today's runs is every bit as foolish as suggesting we're going to get creamed in 10 days based on a particular run. there's a reason that the NHC doesn't forecast beyond 5 days. You just have to take it one day at a time. If I was confident nothing was going to happen....I certainly wouldn't be spending time here.

[Dean4Storms]

00z ECM EPS is up to 80% chance of TD formation in the Western Carib. Sea by the 8th. It has been steadily increasing for a week now during the 4th to 8th time frame.

[tolakram]

Much like last time we won't know anything for sure until 5 days out or less in my opinion. This reminds me of late August when the Atlantic looked incredible unfavorable, upper lows everywhere, and the models showing weak storms here and there but nothing definite.

[WeatherEmperor]

12z Euro coming a bit more into line with GFS by showing low pressure system going to Florida Panhandle




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[Alyono]

12Z EC sends a TS into the Florida Panhandle

[fox13weather]

Seems reasonable that there will be a surge of tropical moisture moving north into the Gulf next weekend. The big question is, will it consolidate into a formidable storm?? Even a TS into the panhandle brings coastal flooding to Florida west coast.

[TheStormExpert]

I’m not seeing anything to assume that this will amount to much.

[johngaltfla]

Seems reasonable that there will be a surge of tropical moisture moving north into the Gulf next weekend. The big question is, will it consolidate into a formidable storm?? Even a TS into the panhandle brings coastal flooding to Florida west coast.

And special thanks to your team at Fox 13 for all you do, especially during hurricane season.

I'm hoping the high pressure builds in and pushes this further west but it is way to early to tell.

[LarryWx]

I know it is the 18Z GFS, my "favorite" run lol, but like the 12Z GFS, it gives FL a big blow with a strong TC hit on S FL on 10/7.

The period 10/7-10 was suggested by the 3 main 12Z ensemble runs to be the period FL is at highest risk from getting a hit from below.

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.

[ronjon]

From NWS Tampa Bay AFD this afternoon:

Late in the week the global models are beginning to come more in line
indicating the potential for an area of low pressure to move
north out of the western Caribbean into the Gulf of Mexico
and will need to continue to monitor the evolution of this
system during the week. No matter what though it does look
like deep moisture will overspread the region leading to
scattered to numerous showers and a few thunderstorms for
Thursday through Sunday.

[caneman]

I know it is the 18Z GFS, my "favorite" run lol, but like the 12Z GFS, it gives FL a big blow with a strong TC hit on S FL on 10/7.

The period 10/7-10 was suggested by the 3 main 12Z ensemble runs to be the period FL is at highest risk from getting a hit from below.

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 y 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.

Especially since most people in Pinellas county still haven't had their debris picked up. The Largo,Bellaire, Seminole area was hit especially hard. Lots of trees, large branches and telephone poles down. Not sure if we had tornados, micro bursts, or just a bad cell from Irma but the damage in this area was far worse than other areas in the area.

[LarryWx]

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.

[TheStormExpert]

18z GFS already POSSIBLY hinting at a major pattern change for the Eastern U.S. with our first significant cold front of the season come mid-October. Usually if there is going to be something significant coming out of the Western Caribbean and cutting across Florida or affecting the U.S. it would have to happen by then before things shut down.

[LarryWx]

Further to my post above, I think it has to do with the development or not of that separate GFS Cuban disturbance as stated and not the EPAC H because that EPAC H has been on about every GFS run for several days, including when it showed significant hits to FL from the W Caribbean. It is that Cuban disturbance that has changed on the GFS, not the EPAC H. So, that is the most important factor imo as far as whether or not FL has a real threat in about a week.

Edit: The Happy Hour (18Z) GEFS continues with the other GEFS of today with the idea of little threat to FL from the W Caribbean in about a week. The contrast with the 0Z/12Z EPS is interesting.

[psyclone]

18z GFS already POSSIBLY hinting at a major pattern change for the Eastern U.S. with our first significant cold front of the season come mid-October. Usually if there is going to be something significant coming out of the Western Caribbean and cutting across Florida or affecting the U.S. it would have to happen by then before things shut down.

I did some digging and discovered that KTLH had been as cold as 33 degrees about 2 weeks before hurricane Kate made landfall just to the west in November 1985. October of that year had been quite warm. The current CPC 8-14 day outlook shows Florida remaining warmer and wetter than normal but there is a large area of dryer and cooler temps to the west and that has been making some progress to the east over the past few day's outlooks.