KWT wrote:Frank2 wrote:Per the GFS STRONG westerlies are forecast to drop southward in the next 10 days with a rapid progression of strong high pressure systems from Canada - just a guess but with snow already just north of the border (snowing in Alberta yesterday), the season is almost at an end:
https://www.tropicaltidbits.com/analysi ... 506&fh=360
The same GFS with the well known bias for overdoing troughing and digging cold shots too far south?
Regardless of that we are now entering the danger time period for S Florida in pure climo, though it is good to see that shear holding in place...that IMO is more likely to save the USA than over blown troughing from the over progressive GFS..
The GFS has been advertising the lowering of the westerlies and attendant large strong surface highs to march eastward across the N. CONUS for a few days now. Par for the course - it's nearly October. As for the screaming upper level conditions through the Gulf and Caribbean, those conditions won't necessarily change on a dime.... so sure, that's a good thing. Having said that however, these hostile upper level conditions are NOT a result of a larger global El Nino split jet pattern but as I see it more of a result of our recent summer pattern anomalous mid level ridging across the W. Atlantic and E. Conus and accompanying recent/present high latitude zonal pattern across much of the U.S. during recent months. I'm simply implying that I think that our present Conus mid-latitude flow under that zonal regime has partially contributed to a deep layer "top down" high pressure area to largely park over Texas causing the upper flow to drop southward and then across much of the Gulf and Caribbean like a TUTT like feature. My point is that I believe with the dropping westerlies, will also evolve how/where the near term long wave pattern is apt to set up. Whether this simply implies a lower latitude progressive short wave pattern, or greater troughing to set up along the E. Conus Seaboard, over the Midwest, or Western U.S. I don't know. What I believe though is that seasonal pattern changes over the CONUS will begin to occur and only then (about a week/10 days?) will we be able to better assess if and how those changes/wrinkles in both steering and upper level flow might impact W. Atlantic regions. Regardless, I don't see the above impacting additional tropical cyclones from developing.... but simply impacting "where" they develop (BOC vs. E. GOM, extreme S.W. Caribbean vs. N.W. Caribbean, or near the N.E. Caribbean to points north for hundreds of miles etc). Track, strength, and storm lifespan will then certainly be dictated if present strong upper level conditions remain unchanged or if evolving long wave changes cause "game board checker pieces" (conducive upper level anticyclonic flow or hostile upper level shear) to shift.
Judging from the type of season we've seen thus far and considering data recently presented or quoted by others, i'd guess that:
1) we're at least 2-4 new storms away from the end of the season
2) Even Kirk aided by a photon torpedo won't break through the current "shear (upper level winds) wall of terror"
3) Fast forward 8-14 days to see where the first significant fronts begin to drop; cue to building upper level heights and a relaxing flow over the E. Gom/W. Caribbean to occur
IF we see strong negatively tilted cold fronts digging south further west such as around the Central Plains and West of the Mississippi. On the other hand, I think a primarily continued zonal pattern across the West/Central U.S. with fronts beginning to drop southward near the Eastern Great Lakes to U.S. E. Seaboard may suggest some continued hostile upper level conditions extending southward (at least into the Northern & Central Gulf). If I were a betting man, i'd guess the greatest threat of a significant end-of-season hurricane exists for either Central America or Eastern Cuba from mid to late October.
recently with its Caribbean bias. It’s certainly possible this time of the year down there. This mornings 06z run ends with a potential storm in the nw Caribbean Sea.
