Rabbit
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seems that has added 96L on the nontropical system
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cieldumort
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New invest up. There exists a drawn out potpourri of convection associated with surface to mid-level troffiness in the western Atlantic into the Caribbean, with numerous surface to mid level swirls, some more pronounced than others, with x94L having been the most prominent. is now tracking 96L in the central Atlantic, around 30N 53W. This feature was already analyzed by TPC as a 1011 mb low center Wednesday. Movement is generally east this morning. estimates winds at 25 knots, which both the former pressure estimate and max sustained wind may be conservative, based on ship reports which suggest pressures have been down around 1007-1009 and max winds closer to 30 knots. This system is very nearly, if not already, a depression, although shear has been an inhibiting factor.
NHC discusses it in the 10:30 :
1. A SMALL AREA OF LOW PRESSURE IS LOCATED ABOUT 800 MILES EAST-
SOUTHEAST OF BERMUDA. ALTHOUGH UPPER-LEVEL WINDS ARE NOT FAVORABLE
FOR SIGNIFICANT DEVELOPMENT OF THIS SYSTEM...ONLY A SMALL INCREASE
IN ORGANIZED THUNDERSTORM ACTIVITY COULD RESULT IN THE FORMATION OF
A TROPICAL DEPRESSION. THE LOW IS EXPECTED TO MOVE NORTHEASTWARD
AND BECOME ABSORBED WITHIN A FRONTAL BOUNDARY IN A COUPLE OF DAYS.
The non-tropical low which was rather quickly acquiring some tropical characteristics in the far eastern Atlantic I mentioned yesterday has remained generally symmetrical, cold-cored, and has given up much of its convection which existed Wednesday. It was already being tracked as an Invest by SSD, although had not assigned it a number for . Nothing much doing there so far today.
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cieldumort
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Invest 96L is now TD15. Winds estimated at 30 knots and pressure at 1011mb, per .
(LINK)
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Lee-Delray
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TD #15 will be a 24-36 hour fish spinner, never making it to TS strength. Interesting the keeps talking about the activity near Cuba, but says nothing will come of it.
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cieldumort
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ID T1 TIME LAT LON DIST HDG WDIR WSPD (In knots)
SHIP S 1800 29.10 -50.50 60 180 190 35.0
Ship report from 1800Z within miles of the coc was reporting sustained winds out of the south at 40 mph. Just a very slight increase in organization would probably force s hand at naming 15 in real-time. The window for such further intensification is forecast to close as shear turns around and starts to beat on 15 from the north, and by default, if for no other reason, substantially increases in intensity as the cyclone travels along a forecast northeasterly heading. However, should 15 continue to proceed in a more due easterly direction the net shear over the system could be less, and 15 has already shown a propensity to fend off shear quite well, beating out numerous model runs which anticipated decoupling by now.
As for the Caribbean, we probably need to see something really start turning at the surface before takes more notice. The only notable turning at the surface is still well inland (94L). For now, it's an impressive trof, with occasional transient lows.
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cieldumort
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The non-tropical low in the far eastern Atlantic has now been tagged, 97L. Just picked up an ST 1.5 from SSD, which is not surprising. Initially, 97L was getting some T 1.5s on Wednesday, but has since shown to be more of a symmetrical, cold-core type hybrid. This feature has been drifting southwest, over progressively warmer waters, and remains in a relatively low shear environment.
Recent T numbers from SSD
DATE/TIME LAT LON CLASSIFICATION STORM
12/0600 UTC 28.7N 18.7W ST1.5/1.5 97L -- Atlantic Ocean
12/0545 UTC 30.2N 49.5W T1.5/1.5 15L -- Atlantic Ocean
Worth noting that post-eclipse 15L is running T2.5 from CIMSS ADT, with a Raw T of 3.0 (Shear scene type) and a center temp +10.6C.
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allan
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Very quiet in here for 2 invests out there..
98L and 99L are both on the Navy
x94L becomes 99L as 98L is tagged for a closed low with little convection.
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Allan Reed - 18,9,5
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cieldumort
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99 (birthed from x94, no doubt) continues in the tradition of its predecessor, embattled with dry land. Hard to not have been more impressed with what was a hybridizing low that formed farther northeast along 94s associated trof (this low centered roughly east of Bermuda at the time), and dropped some pressures to about as low as 998 or so, while bumping winds up above 40 knots. Later, what was left of TD15 had gone on to merge with the same trough, and it's a little surprising no invest tag went up on that location, although the waters ahead are quickly cooling, and shear was certainly not light, overall.
Looks like 98 has had a little more going on at the surface, and despite very strong shear, has been able to pop an occasional shower or two right in the coc. Some feeble but obvious attempts at some banding still seem to be holding on. If shear lessens up a bit before this one moves inland, I think maybe just maybe something can actually take. Not a lot of there there in either one, just yet. Par for the course for mid Octobers.
It would be helpful should not only be experiencing processing delays today, but additionally, neither Invest has a floater on it yet. Ships and buoy data in the region are sparse to nonexistent. For most of today, conventional satellite seems to have been the best divining rod we have had to work with on these two.
Interestingly, if either of these guys can pop, about half of the tentative model guidance suggests that a turn northward into upper Mexico-Texas, or even northeast of there, could become very possible.
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danielw
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While there isn't much mention about the broad trough in the Western and SW GOM.
I did find a few honorable mentions in the various discussions tonight.
TPC has even generated a model run on the poorly ( at this time ) organized system.
Latest Model Run on the GOM Low
QUANTITATIVE PRECIPITATION FORECAST DISCUSSION
NWS HYDROMETEOROLOGICAL PREDICTION CENTER CAMP SPRINGS MD
607 PM EDT MON OCT 15 2007
FINAL DAY 1...DAY 2 AND DAY 3 DISCUSSION
VALID OCT 16/0000 UTC THRU OCT 19/0000 UTC
REFERENCE AWIPS GRAPHICS UNDER...PRECIP ACCUM - 24HR
DAY 1...( 8PM EDT Monday to 8PM EDT Tuesday)
... E CNTRL GULF COAST...
WHILE (total rainfall amounts) DETAILS ARE NOT EXACT...ALL MODELS GENERATE SGFNT (significant)RAINS INVOF(in vicinity of) THE E CNTRL GULF COAST AS RETURNING PWS(preciptable water amounts) IN THE 2.25 INCH RANGE ARE LIFTED BEHIND AN EVOLVING WARM FRONT AS A STRONG UPPER LVL(level) JET STREAK SWINGS BY CONTRIBUTE TO STRONG DYNAMIC FORCING.
TREND IN BOTH THE AND WHICH HAS STRONG SUPPORT FM(from) THE CANADIAN GEM (model) WAS TO BE FASTER WITH INITIATING ACTVTY(activity) ALONG THE GULF COAST.
FOR NOW LEANED A LITTLE MORE TOWARDS THE GEM FOR THE FCST(forecast) WHICH ALLOWED HEAVIER PCPN(precipitation) TO ADVANCE A LITTLE FARTHER NWD(northward) THAN THE OR WHICH MAY OR MAY NOT BE RELATED TO SOME
FEEDBACK ISSUES. WHETHER THE VERY HEAVY AMTS(amounts) ARE CORRECT OR NOT IS SPECULATIVE..BUT THE MSTR AVBLTY(moisture availability) AND DURATION OF THE ACTVTY(activity)
SUGGESTS THAT AMTS(amounts) COULD APCH(approach) THE 6.00 TO 7.00 INCH TOTALS AT
LEAST ON THE VERY LOCALIZED SCALE.
DAYS 2 AND 3... (Tuesday night thru Wednesday night)
...GULF COAST AND SOUTHEAST...
WITH HEIGHT FALLS OVER THE PLAINS WEDNESDAY AHEAD OF THE SHORTWAVE OVER THE INTERMOUNTAIN WEST.... THE REMAINS OF AN OLD BAROCLINIC ZONE OVER THE SOUTHERN GULF SHOULD BEGIN LIFTING NORTHWARD THE
NEXT FEW DAYS. THIS PATTERN ALONG WITH THE ENTRAINMENT OF MOISTURE ASSOCIATED WITH A WEAK LOW-LEVEL CIRCULATION WEST OF THE
YUCATAN THIS AFTERNOON SHOULD SET THE STAGE FOR MODERATE TO LOCALLY HEAVY RAINS OVER THE EAST CENTRAL GULF COAST INTO PARTS OF THE DROUGHT-STRICKEN SOUTHEAST.
THE AND MODELS WERE CERTAINLY OVERLY DEVELOPED WITH THE BROAD SURFACE LOW OVER THE CENTRAL AND NORTHWEST GULF COAST... WITH THE AND GENERALLY FAVORING A WEAK OR ALMOST NON-EXISTENT SURFACE LOW REACHING THE CENTRAL GULF COAST TOWARD THE START OF THE PERIOD.
REGARDLESS OF WHETHER THIS SYSTEM EXISTS OR NOT...OVERRUNNING MOISTURE AND A FAIRLY SLOW-MOVING BOUNDARY SHOULD LEAD TO SOME
HEFTY RAINFALL TOTALS FROM THE MOUTH OF THE MISSISSIPPI AND FLORIDA PANHANDLE INLAND THROUGH ALABAMA AND THE SOUTHERN
APPALACHIANS.
edit: While the system isn't a purely tropical system at this time-1210AM EDT. The combination of the purely tropical airmass, northward moving warm front, and other upper atmosphere disturbances appear to be setting the stage for a Heavy Rainfall event.
Per the HPC maps. The Eastern Gulf Coast is the Coastline east of Appalachicola,FL
http://www.hpc.ncep.noaa.gov/images/us_bndrys2_print.gif
EXCESSIVE RAINFALL DISCUSSION
NWS HYDROMETEOROLOGICAL PREDICTION CENTER CAMP SPRINGS MD
1002 PM EDT MON OCT 15 2007
...VALID 03Z TUE OCT 16 2007 - 00Z WED OCT 17 2007...
...REFERENCE AWIPS GRAPHIC UNDER...DAY 1 EXCESSIVE RAINFALL...
CNTRL GULF COAST...
SATL IMAGERY IS SHOWING CONVECTION TRYING TO ORGANIZE IN AN AXIS
OF HIGH PWS SURGING NWD TOWARD THE CNTRL GULF COAST. MODEL
GUIDANCE CONTS TO SUGGEST THAT THERE WL BE POTENTIAL FOR HEAVY
PCPN AMTS ALONG THE GULF COAST...ALTHOUGH THE APPEARS TO HAVE
SOME GRID SCALE ISSUES. GIVEN THE LATEST SATL IMAGERY AND FAIRLY
GOOD MODEL AGRMNT...BELIEVE THERE WL BE A THREAT OF HEAVY RAINS
SPREADING NWD INTO THE CNTRL GULF COAST OVERNIGHT. ISOLATED SHRT
TERM PCPN AMTS OF 1-2" AND ISOLATED TOTALS APPCHG 5" POSSIBLE
ALONG THE CNTRL GULF COAST THIS PERIOD.
http://www.hpc.ncep.noaa.gov/discussions/qpferd.html
http://www.hpc.ncep.noaa.gov/qpf/qpf2.shtml
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cieldumort
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If it weren't for all the dry air and nearby high shear I would say 99L is on the West GOM Fast Track to pull it off. But, unlike last month, times have changed. Still, looking at the post-eclipse loops tonight, particularly the IR2, it is hard not to argue that 99 has been drawn north and is attempting to recenter about a new plot near 22.5N 93.5W, but this does not appear to be firmly rooted in the surface at this time.
Should 99 become a TC before long, as it might not have much time before it gets burried in its own new plot under the mounds of shear and dry air, it could draw away some of that rich fetch of moisture heading into the southeast. Ultimately, more and more models that have locked on to it have moved it northeasterly, anyway, and hopefully this brings more welcome rains to the region, regardless.
In the mean time, what a nice slug of deep tropical thunderstorms just off the coast in the northeastern GOM!
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cieldumort
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There is little room left to doubt that Invest 99L has become slightly better organized than just 12 hours ago, and considerably better organized than 24-48 hours ago. has just bumped up the estimated winds from 20 knots to 25, and has changed the wording of the most recent from "nothing expected" to the following:
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1130 AM EDT TUE OCT 16 2007
FOR THE NORTH ATLANTIC...CARIBBEAN SEA AND THE GULF OF MEXICO...
1. SATELLITE IMAGES AND SURFACE OBSERVATIONS SHOW AN AREA OF LOW
PRESSURE IN THE WESTERN GULF OF MEXICO CENTERED ABOUT 250 MILES
SOUTHEAST OF BROWNSVILLE TEXAS. SHOWER ACTIVITY IS DISORGANIZED AT
THIS TIME BUT THERE IS A POTENTIAL FOR SOME DEVELOPMENT TODAY OR
TOMORROW BEFORE THE UPPER-LEVEL WINDS BECOME UNFAVORABLE IN THE
AREA. THIS SYSTEM IS EXPECTED TO MOVE NORTHWESTWARD TO NORTHWARD.
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Thunderbird12
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99L is now inland. It was nothing much of tropical significance, but it will enhance the tornado threat over TX/LA/AR as it gets absorbed into a very intense mid-latitude system developing over the central U.S..
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Storm Hunter
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nice little low off the central east coast of Florida, however with the front back over central US... Upper level winds don't give it much of a chance... which it should move north a bit then out to sea with the front coming to the east coast... Sounds like Sever wx. season is kicking in now. Here in NW Florida, were still about 20Inches behind in rainfall this year... YIKES!
10 Days away from my 1 yr anniversary of the F-0 Intercept.. haha... Looks like might get another chance in coming days!
Tropics look to be shutting down out to the east in the far atlantic.... Upper level winds are screaming over the region....
--------------------
www.Stormhunter7.com ***see my flight into Hurricane Ike ***
Wx Data: KFLPANAM23 / CW8771
2012== 23/10/9/5 sys/strms/hurr/majh
Edited by Storm Hunter (Wed Oct 17 2007 12:03 PM)
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cieldumort
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99 - and it's associated trough - was a very prolific wind-maker while approaching the coast. Ship report from very near the center of circulation late overnight came in at 34 knots, and an oil platform with an anemometer at around 400 feet was blasted by hours and hours of sustained winds between 40 and 67 mph, with a pronounced wind shift noted in its obs during passage. Pressure in 99 looked to have dropped to about 29.65 or so, before coming ashore.
Now inland, it has already had enough spin of its own, combined with a few slugs of moisture, friction and daytime heating, to pop one tornado in Buna, Tx. this morning (inland from the uppermost Tx coast.) SPC has had this to say about it in the Day 1:
LASTLY...ANOTHER ZONE OF ENHANCED SVR THREATS WILL EXIST FROM THE
UPR TX COASTAL REGION NWD INTO LA AND AR ASSOCD WITH A PLUME OF RICH
TROPICAL MOISTURE SURGING NWD WITH A GULF IMPULSE. MODEST LOW-LEVEL
WIND/SHEAR PROFILES ALREADY IN PLACE WILL CONTINUE TO IMPROVE WITH
TIME AS THE SRN PLAINS UPR JET PUNCHES EWD AND LOW-LEVEL SLY FLOW
RESPONDS. HIGHEST POTENTIAL FOR EMBEDDED SUPERCELLS WITH
TORNADOES...SOME STRONG...WILL SPREAD NEWD FROM THE UPR TX COAST/WRN
LA AT MID-DAY AND REACH THE MID-SOUTH/OZARKS BY TONIGHT.
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