Saturday, June 26, 2010

Brownsville, TX South!



Brownsville, TX is the absolute furthest north I would personally forecast Alex to track! The 18z GFS/GFDL are out to lunch! I can't say this enough, but the GFS just can't resolve heat/heat transfer issues!!! I have been following the tropics pretty hardcore since 2002, so I have seen this error too many times to count... I don't have the exact odds, but the majority of the time the GFS is to the right of the actual track, especially more than 48 hours out from landfall... It typically starts to catch on by about 48 hours out, but honestly it should by then!

It notoriously underestimates the strength of the ridge... This error is especially bad when you have a major hurricane releasing mass quantities of latent heat in the atmosphere, which will only pump (strengthen) the ridge even more! Please keep that in mind for later in the season, when I almost guarantee you we will be faced with this! The GFS has this error year round, as it is typically too quick/cold with cold fronts as well... It breaks down the ridge too fast/too much, thinking the cold air will not only head more south, but head more south way too fast! I will say the GFS was able to overcome this problem this winter, as a strong -SOI (El Nino) added momentum to the westerlies... Plus you had a strong -NAO amplifying the pattern, because of blocking downstream in the Atlantic! So it was able to do ok this winter for the wrong reasons... Of course this is only a bias, so it doesn't always happen this way, but again the GFS is HORRIBLE with understanding the amount of heat present in the atmosphere...

I like the 18z HWRF right now the best... I think it will be the closest, even though I do think that Alex has a good shot at becoming a minimal hurricane at landfall... Of course that depends on how much water Alex will have to work with once it pops out in the Bay of Campeche... It went into Belize fairly weak, without having the most defined inner core... Refer to last night's blog post for more information on why that is important in regards to strengthening... I really believe it will spin up fairly quick, but run out of room in the end... I think northern Mexico is the most likely target as of now! I may actually end up being a little too far north in the long run... However, I'll take my forecast from Monday (Southern Texas/Northern Mexico), especially when you consider that almost every model wanted to break down the ridge and allow a path for Alex to strike the northern Gulf coast! Since day one of 93L, continuing tonight, I have always thought the ridge will win!



Notice the GFDI (Similar to the GFDL, but interpolated) on the 0z CSU early track... What a surprise! The GFDL, even with its great resolution, will ALWAYS struggle with the strength of the ridge because it is initialized off GFS model data... In a sense, the GFS fills in the gaps... All I can do is shake my head...

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