cieldumort
Moderator
Reged:
Posts: 2497
Loc: Austin, Tx
|
Invest 94L Ramped up overnight, and back down in the morning
Tue Aug 19 2008 04:12 AM
|
|
|
With so much attention rightfully on Fay this week, a little-noted tropical wave that rolled off the west coast of Africa a few days ago has been on a fast track ramp-up tonight.
At this time microwave passes are still a bit wanting, and the most recent Dvorak out of SAB came in 1.0. The most recent scatt winds came in many hours ago, and a fairly well-defined surface circulation was already present at that time.
It is very possible that the Dvorak estimate out of SAB is, now, already obsolete, despite being less than a few hours old. Using a blend of both the curved band and CDO methods, and even adjusting this down by applying a degree of constraint (.3T/hr), a more timely Current Intensity (CI) might be in the neighborhood of 2.0 - and it is entirely possible that a tropical cyclone has been forming tonight.
From the 2AM EDT TWO, Berg & Franklin give it marks for increased convection, but stress the expectation that upper-level winds become unfavorable in a few days. In an effort to play devil's advocate, I'll point out that 72 hours from now has nothing to do with what the conditions for development are, right now.
There remains much question as to how stacked the surface low is with the robust mid-level center that has really blossomed over the past six hours. Critical to whether or not the feature is, in the first place, a developing tropical cyclone, and going forward, how it will react to a potentially increasingly hostile upper-level wind environment, will be some more microwave, scat passes, and daylight.
The model runs favoring a relatively rapid and pronounced development of 94L tend to find it a weakness in the B/A High, and send it off fishing. Others, which either keep it from developing for many days, or develop it but keep it on the weaker side, unsurprisingly direct it towards the Greater Antilles.
We should know much more by midday.
Midday Edit
After a very good try overnight, morning hasn't been kind to 94L. There is some reason to believe that with the cooling atmosphere at night, it may just be that for the next few the disturbance continues to fare better at night, but then worse entering the next day. If the disturbance hasn't bitten the dust within the next 120 hours or so, at some point in this cycle, it may actually blow up enough to gel.
Track wise, as it now appears 94L probably will not become a tropical cyclone quickly, steering currents will tend to keep pushing it farther west.
Edited by cieldumort (Tue Aug 19 2008 11:37 AM)
|
|
Previous
Index
Next
Flat
Edit
Reply
Quote
