MikeC
Admin
Reged:
Posts: 4635
Loc: Orlando, FL
|
|
The NOAA recon vortex message puts the center at 24.2°N 91.4°W, but the winds only around 35, pressure at 1004, but only 40mph flight level winds.
|
berrywr
Weather Analyst
Reged:
Posts: 387
Loc: Opelika, AL
|
|
28/2329Z - I looked at the latest CIMMS Wind Shear Analysis and Don is now between an area of winds from the north between 5 and 10 knots, not 10 and 15 knots. Movement of Don over the past several hours is just north of due west and I don't see anything in the model data to suggest otherwise. Don is situated under a 200mb upper ridge axis with an inverted trough to it's NE-E-SE and a closed upper low to its west near the tip of Baja California and a mid to upper level upper ridge over the SE USA. Strength of the SE USA upper ridge supports a continued west to west-northwest movement. The more southerly track is not good news for areas in an exceptional drought but those north and east of the track will see beneficial rainfall.
--------------------
Sincerely,
Bill Berry
"Survived Trigonometry and Calculus I"
|
MikeC
Admin
Reged:
Posts: 4635
Loc: Orlando, FL
|
|
Official 8PM position is 24.7N 91.8W, the in the advisory considered it a westward jog. More data from the planes coming later should be interesting.
Also the Central Atlantic wave (no invest yet) has a 20% chance for development over the next 48 hours, so we may go from Don right into tracking another system.
|
MikeC
Admin
Reged:
Posts: 4635
Loc: Orlando, FL
|
|
NOAA plane is sending back 996.1 for pressure readings on this pass. We may be in for a bit of a boom with Don tonight. Hopefully the airforce plane entering shortly can verify this.
|
MikeC
Admin
Reged:
Posts: 4635
Loc: Orlando, FL
|
|
The airforce plane just found a 995.4mb pressure. Pretty much verifies what the NOAA plane found. I'd bet on a special statement from the soon.
|
MikeC
Admin
Reged:
Posts: 4635
Loc: Orlando, FL
|
|
Official vortex message is 999mb from the Airforce plane, probably not enough for a special statement, but should be interesting to see what occurs at the 11PM (10PM CDT) Advisory.
|
typhoon_tip
Meteorologist
Reged:
Posts: 576
|
|
Quote:
Official 8PM position is 24.7N 91.8W, the in the advisory considered it a westward jog. More data from the planes coming later should be interesting.
Also the Central Atlantic wave (no invest yet) has a 20% chance for development over the next 48 hours, so we may go from Don right into tracking another system.
I was considering the possibility that this was a center recapture/reposition as causal to that apparent jog.
Impressively cold persisting quasi-CDO feature, most likely attributed to the fact that the system is currently passing close a region of very high oceanic heat content - with significant thermocline depth as well. This is providing a source of high fuel input that is compensating for any dry air impacts, as well.
So long as we have a TC with a closed circulation, quick pressure falls would likely have to occur given to these powerfully sustaining updrafts as evidenced by IR channels. Most guidance keeps this rather pedestrian; let us hope that is verified. We have seen in the past that pretty satellite presentations are not always confirmed. My personal hope for this was that a pedestrian system would make its way into interior TX and eventually get caught up in the monsoonal flow into OK and other areas that are parched dry and in severe drought.
Currently the wind overlay at TPC, as coarse as it may be, is indicating that the region of impacting NNE shear is bypassing now to the east as the TC moves away; that may also be helping said recapture scenario because the middle and upper level turrets are no longer leaning away from the llv eddy. Fascinating.
|
MikeC
Admin
Reged:
Posts: 4635
Loc: Orlando, FL
|
|
The good news is that it looks like the pop of intensification has settled to around 999mb, at least in the last few passes, motion is west northwest after the recenter/jog, etc. And it looks as if the Tropical Storm warnings will stand. We'll see at 11 though.
|
danielw
Moderator
Reged:
Posts: 3527
Loc: Hattiesburg,MS (31.3N 89.3W)
|
|
It appears that the difference in the NOAA and the Air Force dropsonde pressure reading is 4 millibars.
If I'm reading the drops correctly the NOAA drop recorded 1000mb -41m (-135 ft).
USAF drop reported 1000mb -5m (-16 ft)
135ft - 16ft = 119ft divided by 33.4 constant equals 3.56 or 4 millibars.
One millibar is roughly 33.4 feet or one atmosphere if you are a diver.
As to which one is more correct. I don't know. They both were dropped in a windy area so it appears that they may not have sampled the lowest pressure.
I am not a Met, but the preference for dropsondes is to be in an area with less than 20 knot winds. If my memory serves me correctly. I'll double check.
|
danielw
Moderator
Reged:
Posts: 3527
Loc: Hattiesburg,MS (31.3N 89.3W)
|
|
They are going with 50 mph and 998mb for the 11 PM Advisory.
|
Ed Dunham
Former Meteorologist & CFHC Forum Moderator (Ed Passed Away on May 14, 2017)
Reged:
Posts: 2565
Loc: Melbourne, FL
|
|
As noted in Mike's latest Main Page Update, Don is weakening a bit and the latest Vortex reports a pressure of 1002MB. I think that the difference in the drops were that they were flying at night while aiming for a small center - and somebody missed!
ED
|
Previous
Index
Next
Threaded
Edit
Reply
Quote
