GaWx Posted October 5, 2014 Share Posted October 5, 2014 Only have it to 180 hours, but the 00z was similar to the operational. Interesting. So, unlike the June debacle, the op. GFS actually has support from its parallel run. I don't know that it has significane, but I suppose it is worthy to note your point about agreement this time (well at least for today's 12Z run). I guess I would have liked to have known what recent prior parallel runs have done. Folks, we have a classic tropics related forecasting battle going on: the battle weary hometown underdog and very unreliable GFS vs. the longerm favorite, the steady Euro. Fun times for forecasting. Link to comment Share on other sites More sharing options...
icebreaker5221 Posted October 5, 2014 Share Posted October 5, 2014 Today's 12Z Euro still shows no support for the GFS as it has basically nada for the W. Caribbean. It had only one very weak low on one run. Otherwise, it has had nada. Instead, it has been favoring the EPAC for genesis. The end result is quite different, but the ECMWF and the GFS actually look fairly similar at 96h with a dual-lobe vorticity structure centered over Costa Rica. Only by 120 h do they begin to significantly diverge: the ECMWF having the western vortex become dominant, the GFS favoring the eastern. The difference is fairly subtle, and will come down to whichever side of the gyre (for lack of a better term) can sustain deep convection for longer... which is quite difficult to forecast for any model. Also note that the steering flow is very weak in both models from days 6-9. Even if something does develop in the East Pac, it's not out of the question that it could potentially cross over e.g. the Bay of Campeche. It's still far from set in stone that something will spin up in the Caribbean, but IMO this setup has more merit than the fantasy canes the GFS was spinning up in the beginning of the season. Link to comment Share on other sites More sharing options...
Eyewall2005 Posted October 5, 2014 Share Posted October 5, 2014 Met Steve Gregory.. http://www.wunderground.com/blog/SteveGregory/comment.html?entrynum=247 The tropical environment continues to be generally hostile to tropical cyclone formation, but a gradual decrease in wind shear and a somewhat more favorable overall flow pattern MAY begin to take shape, particularly in the western CARIB, next week. The GFS is famously far too aggressive in developing tropical cyclones in the western CARIB both at the start and end of the hurricane season – and has been ‘forecasting’ a tropical formation in the western CARIB between Days 13-15 seemingly during every other model run for over the last couple weeks. HOWEVER, over the past few days, much greater continuity in these forecasts has appeared, with several other global models also (very roughly) picking up on this trend as well. Though the probabilities of a cyclone formation have increased – with a formation increasingly likely in about 7-10 days in the western CARIB – conditions do not appear favorable for a cyclone to form during the next 5-days. This trend is also in rough agreement with several other global models. Link to comment Share on other sites More sharing options...
Amped Posted October 5, 2014 Share Posted October 5, 2014 Euro actually forms the storm in the E pac south of Honduras, than moves it over the Yucatan. It might reform in the gulf if you extrapolate past 240. Link to comment Share on other sites More sharing options...
jconsor Posted October 5, 2014 Share Posted October 5, 2014 Superstorm- thanks a lot for the info on GFS parallel run. Can you post a link? I haven't been able to find it. Only have it to 180 hours, but the 00z was similar to the operational. Sent from my iPhone using Tapatalk Link to comment Share on other sites More sharing options...
Superstorm93 Posted October 5, 2014 Share Posted October 5, 2014 Superstorm- thanks a lot for the info on GFS parallel run. Can you post a link? I haven't been able to find it. Sent from my iPhone Sure. The output can be found in the 2D section. http://www.emc.ncep.noaa.gov/gmb/STATS_vsdb/ Link to comment Share on other sites More sharing options...
GaWx Posted October 5, 2014 Share Posted October 5, 2014 Met Steve Gregory.. http://www.wunderground.com/blog/SteveGregory/comment.html?entrynum=247 The tropical environment continues to be generally hostile to tropical cyclone formation, but a gradual decrease in wind shear and a somewhat more favorable overall flow pattern MAY begin to take shape, particularly in the western CARIB, next week. The GFS is famously far too aggressive in developing tropical cyclones in the western CARIB both at the start and end of the hurricane season – and has been ‘forecasting’ a tropical formation in the western CARIB between Days 13-15 seemingly during every other model run for over the last couple weeks. HOWEVER, over the past few days, much greater continuity in these forecasts has appeared, with several other global models also (very roughly) picking up on this trend as well. Though the probabilities of a cyclone formation have increased – with a formation increasingly likely in about 7-10 days in the western CARIB – conditions do not appear favorable for a cyclone to form during the next 5-days. This trend is also in rough agreement with several other global models. I feel that Steve Gregory's writeup is very good and makes perfect sense. However, with all due respect to Mr. Gregory, I don't at all agree with him that the GFS "has been ‘forecasting’ a tropical formation in the western CARIB between Days 13-15 seemingly during every other model run for over the last couple weeks". Note that I bolded his reference to days 13-15. If one were to look back at the documentation of the GFS runs on the last two pages of this thread, he/she would realize that the GFS has been very consistent with development in the W. Caribbean near 10/10 since at least that one run on 9/26, nine days ago. Granted, on that run, genesis was, indeed, on day 14 (10/10). However, it has consistently gotten closer than day 14 ever since then. So, genesis hasn't been on days 13-14 in over a week. By the runs of one week ago (9/28), genesis had already moved up to days 11-12. Now it is all of the way up to ~days 3-5. I think it is very important to correct this for the record because it shows that the GFS' timeframe has not at all been slipping since this genesis date of 10/10 first appeared. In showing a genesis that isn't slipping, it shows that it is a totally different situation vs. that May/June horrible debacle and should give the GFS some more credibility than if it were to have continued slipping. Link to comment Share on other sites More sharing options...
wxmx Posted October 5, 2014 Share Posted October 5, 2014 Is this a case of selective memory? The GFS was astounding with TS Dorian, showing 30+ consecutive runs of a TS hitting <80 mi around the Tampico area...with 20+ showing a hit <50 mi around that same area. Intensity, track and timing was incredible that far off. I agree that it has been overly agressive with cyclogenesis, but it hasn't been as bad as some people portrait it. Link to comment Share on other sites More sharing options...
dtk Posted October 5, 2014 Share Posted October 5, 2014 Can we petition Dr. Louis Uccellini to fix the GFS? At this point, it has become a complete joke of a model. Okay, original post was probably too sarcastic....so I'll rephrase. The GFS has the lowest (or at least statistically tied) mean track error (out to 5 day lead time) in the Atlantic basin of any global model over the past three years...basically in the same ballpark as ECMWF. To call it useless is well, useless. The consensus of the ECMWF and GFS model is very, very difficult to beat for track forecasting. TC Genesis is another animal altogether. We don't have good stats that quantify it as nicely as track and intensity errors, but the GFS is certainly high when it comes to FAR. However, I'm not sure that is ammunition to call it "useless", either. Guidance is just that....guidance. It's important to understand what it is and how to use it. Even the best of the best models are (and will always be) imperfect. Link to comment Share on other sites More sharing options...
ohleary Posted October 5, 2014 Share Posted October 5, 2014 Can we petition Dr. Louis Uccellini to fix the GFS? At this point, it has become a complete joke of a model. Yeah, you probably should. The developers at NWS/NCEP have probably never thought about improving the model. What a joke of a model the GFS is. Who would ever want to use the global model with the lowest mean Atlantic track errors (to 5 days) over the past 3 years? Completely useless..... Gold. Link to comment Share on other sites More sharing options...
Eyewall2005 Posted October 6, 2014 Share Posted October 6, 2014 HWRF showing development also.. http://moe.met.fsu.edu/tcgengifs/hwrf/2014100518-simon19e/slp21.png Link to comment Share on other sites More sharing options...
hurricaneman Posted October 6, 2014 Author Share Posted October 6, 2014 The Caribbean system possibilities have gone up a little as there is now support from the HWRF to add to the GEM, NAVGEM, FIM, and slightly by the Euro at the end of its 12z run, the test is if the Euro starts developing it on the Atlantic side or not in the next few model runs to see if this is a possibility Link to comment Share on other sites More sharing options...
Eyewall2005 Posted October 6, 2014 Share Posted October 6, 2014 00z GFS has strong hurricane over keys and clips southern florida. Link to comment Share on other sites More sharing options...
hurricaneman Posted October 6, 2014 Author Share Posted October 6, 2014 it must be an old run of the GFS as this thing would be well west of Florida at this lattitude on the 0zGFS I'm wrong as this moves ESE over the Keys and south Florida as you mentioned Link to comment Share on other sites More sharing options...
GaWx Posted October 6, 2014 Share Posted October 6, 2014 00z GFS has strong hurricane over keys and clips southern florida. This makes 14 GFS runs in a row with SW Caribbean genesis by 10/10! I'm still wondering if the Euro will ever show solid support. Man, I hate EDT. Link to comment Share on other sites More sharing options...
Kory Posted October 6, 2014 Share Posted October 6, 2014 Looks like the NHC is going with possible EPAC development instead of the Caribbean. Appears they're totally discounting the GFS as far as Caribbean development goes. Many times this year we've seen models pick up on potential storms in the SW Caribbean and as we move up in time, it shunts it to the EPAC. Link to comment Share on other sites More sharing options...
hurricaneman Posted October 6, 2014 Author Share Posted October 6, 2014 Its either my eyes are playing tricks on me or there is some sort of vortmax at about 12N 78W which would lend some creedance to the GFS but as weve seen the last few days the convection could die down and nothing comes of it Link to comment Share on other sites More sharing options...
Superstorm93 Posted October 6, 2014 Share Posted October 6, 2014 The fact that we have now have a catalyst makes this slightly more interesting. P41L seems to have an elongated are of vorticity just north of the Panama coast. Obviously it will be important to see where exactly this area decides to consolidate since it would mean the difference between another EPAC storm and one in the ATL. Link to comment Share on other sites More sharing options...
GaWx Posted October 6, 2014 Share Posted October 6, 2014 For the record: Today's 12Z GFS makes it 16 GFS runs in a row with SW Caribbean genesis by 10/10 and subsequent general northward move to GoM! There have been at least 25 GFS runs with similar genesis timing since 9/26. In other words, the GFS timing on genesis hasn't slipped over the last 10 days. However, the Euro continues to show hardly any support! What a battle we have! Last four GFS runs 10/5 18Z : Hits FL Big Bend late 10/15 as TS, then to Brunswick, then out to sea, and then clockwise loop to N. Caribbean 10/6 0Z: Gets to NE GoM 10/16, then turns SE to hit S tip of FL early 10/18 as 984 mb 'cane, then into Atlantic, and then left hook 10/6 6Z: Hits SW FL 10/15 as TS, then to Melbourne, and then out to sea 10/6 12Z: Gets to N/C GoM 10/16, then turns W and hits C. TX coast as 985 mb 'cane 10/20 Link to comment Share on other sites More sharing options...
IsentropicLift Posted October 6, 2014 Share Posted October 6, 2014 For the record: Today's 12Z GFS makes it 16 GFS runs in a row with SW Caribbean genesis by 10/10 and subsequent general northward move to GoM! There have been at least 25 GFS runs with similar genesis timing since 9/26. In other words, the GFS timing on genesis hasn't slipped over the last 10 days. However, the Euro continues to show hardly any support! What a battle we have! Last four GFS runs 10/5 18Z : Hits FL Big Bend late 10/15 as TS, then to Brunswick, then out to sea, and then clockwise loop to N. Caribbean 10/6 0Z: Gets to NE GoM 10/16, then turns SE to hit S tip of FL early 10/18 as 984 mb 'cane, then into Atlantic, and then left hook 10/6 6Z: Hits SW FL 10/15 as TS, then to Melbourne, and then out to sea 10/6 12Z: Gets to N/C GoM 10/16, then turns W and hits C. TX coast as 985 mb 'cane 10/20 12z GEFS members Link to comment Share on other sites More sharing options...
Superstorm93 Posted October 6, 2014 Share Posted October 6, 2014 The ECMWF really isn't too far off from the GFS at all. If you take a simple look at the 850mb vort progression you can see how there is a decent circulation north of Panama, except it elongates the vort into the EPAC where the most convection forms and is able to consolidate P41L into a cyclone. The GFS and its ensembles are all showing the Atlantic vort winning in the end, thus we see TC genesis. Since we already have a decent catalyst in the Atlantic with convection firing, I think this will come down to pure observation. As one of the mets stated, models have a very tough time with connective processes as it is. Link to comment Share on other sites More sharing options...
wxmx Posted October 6, 2014 Share Posted October 6, 2014 The Atlantic energy wins in the GFS because it keeps the anticyclone there...which shears away the EPac energy. Competing energy is usually a sign of a slow breeder. Link to comment Share on other sites More sharing options...
Kory Posted October 7, 2014 Share Posted October 7, 2014 It appears on the latest run that the GFS is trending toward the Euro. Main part of the 850 mbar energy is on the EPAC side of Central America. Link to comment Share on other sites More sharing options...
bluewave Posted October 7, 2014 Share Posted October 7, 2014 It appears on the latest run that the GFS is trending toward the Euro. Main part of the 850 mbar energy is on the EPAC side of Central America. Pretty much as expected with the GFS convective feedback problems and high genesis false alarm rate. Bogus GFS Model Forecasts of Atlantic Tropical Cyclone Genesis http://www.wunderground.com/blog/JeffMasters/comment.html?entrynum=2700 Link to comment Share on other sites More sharing options...
AvantHiatus Posted October 7, 2014 Share Posted October 7, 2014 Yeah, let's just write this one off. Also Western Atlantic potential is now showing up on the GFS. Link to comment Share on other sites More sharing options...
Kory Posted October 7, 2014 Share Posted October 7, 2014 Yeah, let's just write this one off. Also Western Atlantic potential is now showing up on the GFS. That is actually quite disorganized in my opinion. Vorticity is very elongated west to east. Not to mention shear is just ripping across the whole Caribbean. This is in NO hurry to organize in the Caribbean at least. Link to comment Share on other sites More sharing options...
hurricaneman Posted October 7, 2014 Author Share Posted October 7, 2014 Another area that needs to be monitored is the area east of the Lesser Antilles as it does have a sharp wave axis and support from all models even the Euro has a weak reflection landfalling in Bar Harbor, ME at 240hrs Link to comment Share on other sites More sharing options...
AvantHiatus Posted October 7, 2014 Share Posted October 7, 2014 Another area that needs to be monitored is the area east of the Lesser Antilles as it does have a sharp wave axis and support from all models even the Euro has a weak reflection landfalling in Bar Harbor, ME at 240hrs Sleeper TC, here is the NAM progression of the 850mb vorticity http://www.tropicaltidbits.com/analysis/models/nam/2014100712/nam_z850_vort_watl.html Link to comment Share on other sites More sharing options...
Srain Posted October 7, 2014 Share Posted October 7, 2014 Sleeper TC, here is the NAM progression of the 850mb vorticity http://www.tropicaltidbits.com/analysis/models/nam/2014100712/nam_z850_vort_watl.html lol @ the NAM Link to comment Share on other sites More sharing options...
AvantHiatus Posted October 7, 2014 Share Posted October 7, 2014 lol @ the NAM As they say, how can you be wrong 6 hours out? Rotation in visible tho... Link to comment Share on other sites More sharing options...
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