Global model runs discussion

[cycloneye]

If you look at this GFS long range loop,you will see a series of lows emerging Africa.Not buying any of this as its very long range and its very early for that area to be active.

http://www.nco.ncep.noaa.gov/pmb/nwprod ... loop.shtml

[BigA]

The GFS has been forecasting this off Carolina low for a number of runs. I think that the most recent run forms it around 102 hours. I'm not going to expect anything unless the other models start following suit.

[BigA]

Not exactly medium or long range, but the NAM is at it again, forecasting a closed low developing in the Southern Caribbean and then moving toward the Yucatan in the next 3 days. I'll believe it when I see it.

[xironman]

The Euro has something off Carolina at 144 hrs as well.



It would be in one of the few good spots around that time. From Dr. Masters blog http://www.wunderground.com/blog/JeffMasters/comment.html?entrynum=1241.

The jet stream is forecast (Figure 2) to maintain this two-branch pattern over the coming two weeks. This means that the waters offshore of the Carolinas are the most likely place for a tropical storm to form during this period.

Here is a shot of the dead zone off the southeast at 120 hrs

[cycloneye]

GFS joins the EURO on developing a EPAC system in less than ten days.





http://www.nco.ncep.noaa.gov/pmb/nwprod ... loop.shtml

NOGAPS also has EPAC development.

[BigA]

The Canadian (perhaps the epitome of "necessary but not sufficient") is onboard with off Carolina development http://moe.met.fsu.edu/cgi-bin/cmctc2.c ... =Animation

Low first appears at 78 hours.

[cycloneye]

Here is a recap of the models in the 12z run that are showing a system off the East U.S. coast.

[Ed Mahmoud]

Salt grain- Canadian pinches off a upper low off the East Coast, starts tetrograding it beneath the ridge, and has it crossing Florida and apparently becoming tropical in a week.

[xironman]

For the Carolina system we always have the Canadian to show us a storm



The Euro still only seems to show it on one day



The GFS is mooch more progressive this morning, pushing it beyond the GS before any thing could brew.

Morehead City talks about it a bit http://forecast.weather.gov/product.php?site=NWS&issuedby=MHX&product=AFD&format=CI&version=1&glossary=1&highlight=off

MODELS
BECOMING MORE IN LINE SHOWING A SLIGHTLY STRONGER WAVE DEVELOPING
OVER SC MON NT/TUE BEFORE SLIDING E TUE NT/WED. THE GFS STILL
SEEMS NOTABLY STRONGER WITH THIS FEATURE WHICH IS NOT GIVEN STRONG
SUPPORT ALOFT (THAT WE CAN DETECT AT THIS TIME). THE ECMWF/NAM
SUGGESTING A SLOW MOVING SFC FEATURE AS WELL SO CONFIDENCE HIGHER
THAN USUAL OF PIN POINTING WHEN/WHERE IT WILL FORM...THOUGH
STRENGTH STILL UNCERTAIN HAVE LEANED TOWARDS NAM/ECMWF. GIVEN THIS
FEATURES EXPECTED SLOW PROGRESSION EAST COMBINED WITH IMPRESSIVE
PW VALUES...HAVE BUMPED UP POPS ACROSS THE AREA MON NT- EARLY WED.
HPC SHOWING QPF VALUES AROUND 3"...WHICH SEEMS REASONABLE GIVEN
SOME AREAS COULD EASILY SEE MUCH MORE THAN THAT. LOOKS LIKE THE
AIRMASS WILL BE NEARLY TROPICAL GIVEN ITS SATURATED AIR COLUMN AND
MOIST ADIABATIC LAPSE RATES

[lebron23]

nobody will care but, 6z and also 12z GFS extreme long range system in the E PAC hits mexico goes into gulf moves north toward texas ...yesterdays 18z GFS extreme long range weak system into middle texas

[cycloneye]

Its on the 30th of june,a loooooooooooong way out.Only to show the peeps a Tropical Storm in the Bay of Campeche that sundays 12z GFS has.



The 12z ECM also has the BOC system but at a more advanced timeframe than GFS.

12z ECMWF

[ronjon]

Interesting that both the long range GFS and Euro show a pacific originated system cross northward into Mex and arrive in the BOC or off the north coast of the Yuc in 7 to 10 days. GFS has been rather persistent with this development for several days now. Of course, the GFS track record so far this season for sniffing out cyclogenesis is terrible (lots of phantoms - it's getting so bad now that the GFS is forming systems that the CMC isn't).

[SETXWXLADY]

nobody will care but, 6z and also 12z GFS extreme long range system in the E PAC hits mexico goes into gulf moves north toward texas ...yesterdays 18z GFS extreme long range weak system into middle texas

A Pacific cross over storm is not out of the question. It happened twice I know of. Hurricane 10 in 1949 and TS Allison in 1989.
Both made landfall in SE TX. Sigh. where else?

Also I think there may be something in the BOC sooner than models suggest. My models don't cover the Caribbean tho.

[Macrocane]

nobody will care but, 6z and also 12z GFS extreme long range system in the E PAC hits mexico goes into gulf moves north toward texas ...yesterdays 18z GFS extreme long range weak system into middle texas

A Pacific cross over storm is not out of the question. It happened twice I know of. Hurricane 10 in 1949 and TS Allison in 1989.
Both made landfall in SE TX. Sigh. where else?

Also I think there may be something in the BOC sooner than models suggest. My models don't cover the Caribbean tho.

Also Alma-Arthur, it was not exactly a crossover storm but some of the energy from Alma's remnants were responsible of Arthur's formation.

[gatorcane]

I took a look at all publically available global model guidance for the next 10-14 days. We continue to see these models develop nothing of significance in the Atlantic during this timeframe.

This is good news and it continues to point at a very quite June -- maybe July will follow but too early to tell. We'll need to monitor MJO pulses and the possible development of El nino over the coming months.

[gatorcane]

The 12Z GFS develops a closed low off of the ITCZ and tracks it westward eventually losing this low before reaching the southernmost leeward islands. Considering its only mid June and lack of other models in supporting this idea makes me think what we'll see is a nice cluster of showers and thunderstorms in the ITCZ (which will spark off a thread or discussion later this week or weekend)... that breaks away and eventually goes poof with no development expected.

This area is also a bit too far south as well:

Here we are at 114 hours:


I'm guessing the wave the GFS is after is the one currently about ready to exit Africa. Again it is early to be looking out here but nothing else is expected anywhere else in the Atlantic for the forseeable future so it will give members something to contemplate in the mean time:

[Ed Mahmoud]

New GFS develops a tropical depression in the Atlantic from a system that hugs 10ºN and stays South of the Westerlies of Tropical Doom.



The vorticity that develops comes off the Coast of Africa below 10ºN in 3 days, and while there is a nice blob over Africa, it'd have to move almost 50º latitude near the fat part of the Earth (latitudinally speaking) to make it.




My gut, GFS is smoking something from a pipe, but we shall see...

[cycloneye]

If you look at the GFS loop,that exits Western Africa around 96 hours so that big convection area inside the continent may be it.

http://moe.met.fsu.edu/cgi-bin/gfstc2.c ... =Animation

[Ed Mahmoud]

If you look at the GFS loop,that exits Western Africa around 96 hours so that big convection area inside the continent may be it.

http://moe.met.fsu.edu/cgi-bin/gfstc2.c ... =Animation

If you look at 850 mb vorticity, which I find an easier way to track things, the vort max that the GFS develops hits the coast near 72 hours. Of course, the vort max and the blob may not be exactly co-located.


It is a nice blob...

[cycloneye]

GFS may not be alone on the MDR system as the EURO shows a strong Tropical Wave for June standards moving westward,but it weakens before it reaches the Lesser Antilles.Then it flares up in the Central Caribbean again.Take a look at the 12z run in a loop below.

12z ECMWF