mezzacyclone

This is serious from the "in depth" discussion adv 19: IT SHOULD BE NOTED THAT THE GLOBAL MODELS ARE FORECASTING A VERY FAVORABLE PATTERN OF UPPER-LEVEL WINDS OVER THE NORTHERN GULF OF MEXICO BY 72 HR. SHOULD THIS VERIFY AND SHOULD ISAAC ESTABLISH AN INNER CORE...THE CYCLONE COULD BE SIGNIFICANTLY STRONGER THAN CURRENTLY FORECAST. Fair to say the inner core`s going to be a given so the upper conditions could well be the only factor in deciding if Isaac turns out to be a monster?

NHC last fix at 20.8 75.3 ties in well with sat imagery showing the LLC thereabouts, heading NW and recon shows the centre right over Bahia Rio Seco coastline (Holguin province SE Cuba) maybe slightly inland no more than 30 miles 21.10 75.67 as we speak. Looks like Isaac has a run 300° NW just off the Cuban coast and between the Bahamas running over the Fl keys & with everything going for re-strengthening then the projections for entry just East of the Mississippi Alabama shelf somewhere between Dauphin Island and Pensacola (MS, AL & FL border region) are seriously worrying and further raising concerns for the surge into Chandeleur sound, Lake Borgne & the levys of N.O?

70kn (80.5mph) FLW peak 10 sec. avg. lat17.10 lon70.38. 70 miles ENE from NHC`s last LLC plot @ 16.8 71.4 994.8mb ESP reading lon16.783 lat71.383

66kn (75.9mph) FLW (30 sec avg.) a short while ago (lat16.05 lon69.28 approx 130miles due S of santo domingo DR) not quite `Cane status at Surface (est 66mph) but definitely getting their.

Mission 10`s picking up some westerly SMFR 10s peaks of 52kn (59.8mph) now lat15.01 long70.98 with a circulation earlier @ 15 69.6 where the dropsonde went down with a 1000mb MSLP,,,, So a shift south (by something in the region of 100 miles?) is clearly troublesome as the Haitian/DR mountains could have severely pegged it back but more open high SST seas look in the path with Jamaica and the Grand Caymans awaiting but will strengthening introduce a tighter turn? Their really scrutinising this one? 11:33bst update: 58kn (66.7mph) peak 10sec FLW @ lat16.11 lon -69.43 on AF300 mission 10 NE > SW sweep over suspect centre, Strengthening signs? Increasingly dangerous signs if it don`t start to veer NWards asap with an increased chance of `cane status sooner rather than later and poss 2 status in the GOM?

Holding on but looking out of sorts with 43kn winds despite dry air drawn in recently and lightly moderate shear but multiple circulations appear evident with south and north (weaker) vortices?, likely the (T)UTT had decoupled the main LLC but current mission 3 may find more strength surrounding the strengthening southern vortex? One noticeable point is visible outflow bands particularly over Venezuela/Guyana coastal areas? http://rammb.cira.co.../rmtcnhvis8.gif USAF Recon is headed SW over Dominica (21:18 bst) and over the fading NWern circulation with a lowest ESP of 1004mb and NOAA (mission 4) is just leaving Barbados base. I`d say we are at a point where Isaac is getting himself slowly better organised despite the re-occurring dry westerly air and shear barriers and it should not be such a surprise that he will look most impressive by tomorrow`s end? Upper Trough caveat upheld

Their did look some displacement earlier but it really looks to be coming together now! WOW, 995.5mb 15.867N 57.400W,,,,

below VDM Iceb touched on reinforcing that Isaac`s here, soon to slow down & not too fussy over any diminishing shear headaches Product: Air Force Vortex Message (URNT12 KNHC) Transmitted: 21st day of the month at 19:17Z Aircraft: Air Force Aircraft (Last 3 digits of the tail number are 307) Tropical Depression: Number 9 (flight in the North Atlantic basin) Mission Number: 1 Observation Number: 09 A. Time of Center Fix: 21st day of the month at 18:58:40Z B. Center Fix Coordinates: 15°20'N 53°20'W (15.3333N 53.3333W) B. Center Fix Location: 448 miles (722 km) to the ENE (70°) from Bridgetown, Barbados. C. Minimum Height at Standard Level: Not Available D. Estimated (by SFMR or visually) Maximum Surface Wind: 40kts (~ 46.0mph) E. Location of the Estimated Maximum Surface Wind: 20 nautical miles (23 statute miles) to the ENE (61°) of center fix F. Maximum Flight Level Wind Inbound: From 146° at 44kts (From between the SE and SSE at ~ 50.6mph) G. Location of Maximum Flight Level Wind Inbound: 21 nautical miles (24 statute miles) to the ENE (60°) of center fix H. Minimum Sea Level Pressure: 1005mb (29.68 inHg) - Extrapolated I. Maximum Flight Level Temp & Pressure Altitude Outside Eye: 24°C (75°F) at a pressure alt. of 304m (997ft) J. Maximum Flight Level Temp & Pressure Altitude Inside Eye: 25°C (77°F) at a pressure alt. of 246m (807ft) K. Dewpoint Temp (collected at same location as temp inside eye): 25°C (77°F) K. Sea Surface Temp (collected at same location as temp inside eye): Not Available L. Eye Character: Not Available M. Eye Shape: Not Available N. Fix Determined By: Penetration, Radar, Wind and Pressure N. Fix Level: 1,500 feet O. Navigation Fix Accuracy: 0.02 nautical miles O. Meteorological Accuracy: 2.5 nautical miles Remarks Section - Remarks That Were Decoded... Maximum Flight Level Wind: 44kts (~ 50.6mph) in the northeast quadrant at 18:51:00Z Sea Level Pressure Extrapolation From: Below 1,500 feet Remarks Section - Additional Remarks... SPIRAL BAND

Noticed a few 42kn (48.3mph) 30 sec. avg. Fl lev winds just NE of LLC, 10 sec. avg. peaks 44knots, 1005mb @ 15.2833N 53.3333W

as expected, NHC have increased the max wind probs across the whole range and Cat1 status for 8am Thurs is 48%, but this is still reserved IMO. Just about every model now has TD9 tracking between the area slightly N of the Brit virgin Isles to the latitude 14.6N (62.4W) or roughly 100 miles due W of Martinique. AF307 is headed SE through the outer bands 15.9N 55.9W, MSLP est @ 1010mb so far,,,

etc.And LOOK where Ivan tracked nearby SS, don`t wanna "little bit of history repeatin"

Can we say that`s quite a lethal track Ice? staying off Haiti/DR/ ECuban coast before N turn? Be interesting watching the max wind probability table in how it changes in the coming days?

Worryingly the form horses are showing uniform plots and are causing heightened concerns for FL residents? https://forum.netweather.tv/gallery/image/16151-t168-2108-00z/ CMC skirts the Bahamas further east http://moe.met.fsu.e...82100/slp24.png Hazard a guess that`s its an unofficial TD by now taking into account those cold tops, N&W banding, IR flaring and overall gen appearance etc? Recon (today 15:30 EDT) shifted the suspect area sweep slightly further NWest confirming the speedy momentum that many in the cone would prefer it keeps! and lets not forget how impressive 96L looks

Recon 16:30 local time today, 94L is still sched for tomorrow evening 18z over the area 500 mile west of Martinique 15.5N 53W.What with 96L into the fray then it`s all go and difficult to keep up? I dunno how SS handles `em all what with the far east/pacific etc.?

I`m goin with that too SBFlight Recon maybe out earlier than Tuesday? Euro and now GFS looking at a gulf entry with Isaac, Is it a matter of time before one of these "Crying wolf" tendencies turns out to be a Major landfall?

furthermore, we could well be facing 93L by tomorrows end? GFS have been chopping and changing with intensity/path (fishy) etc but it`s not that common for such an early advisory only just coming out of Guinea-Bissau! THIS WAVE HAS BEEN TRACKED ACROSS AFRICA THE PAST FEW DAYS AND EXHIBITS VERY DISTINCT CYCLONIC CIRCULATION IN THE LOW-LEVELS. WHILE THIS CIRCULATION IS NOTED IN GLOBAL MODEL DATA BETWEEN 600-850 MB...THE ONLY APPARENT SURFACE CIRCULATION IS LOCATED ON THE NORTHERN EXTENT OF THE WAVE AS A 1005 MB LOW CENTERED NEAR 16N12W ACCORDING TO RECENT SURFACE OBSERVATIONS ACROSS W AFRICA.

Ernesto-esque? Current Forward speed could coincide with east coast US mainland trough pushing through Southern Georgia/S Carolina come wed 15th and encourage a more NWesterly motion but as Ernie did maybe this could stave off shear and go TS to low end cane cat status but current probability favor's a TS @ 56% as early as 6-7pm BST tomorrow? out to 120hrs gives an all combined category `cane status @ 23%, changes to this will be interesting on the obvious favourables (or more accurately not so`s) along the way. I think it`s palpable however to say this won`t be a short lived "Florrie"? on the provisio of east Caribbean survival may I add

Figure we have a green light for Gordon here SB ;o) Let's run a dedicated thread with it?

yup, GFS was more or less bang on with the N&Westrn ridging & came very close, HWRF 2nd, BAMM 3rd, GFDL4th & NAM out of it totally with a TX hit? But maybe an ever so slight jig WNWards on the latest`s give a sea track for a while? here`s the CIMMS pic showing the pattern FWIW, CIMMS steering

Mission 11 on the runway and data should be coming back for midnight and i think most of us anticipate the strengthening SS? considering the last images I wonder how much sub 984mb will he go? The SW GOM/Campeche bay track is interesting me if he holds up over quintana roo, campeche, yucatan landfall etc.with anything between a 250-400 sea track before eastern Mexico shore?

So he made it, thanks to all the informative posts people