Why Franklin may LOOP after all

[mike18xx]

(Loops of above imagery: http://www.ghcc.msfc.nasa.gov/GOES/goeseastconuswv.html.)

The upper-air divergence zone is already passing Franklin's longitude, meaning the ridge ("red zone") behind the trough
("blue zone") will begin building north of the tropical system before it has moved appreciably to the northeast.

[Matt-hurricanewatcher]

The cyclone should fellow the back side of the weakness/trough to the north. So it is to late for the ridge to get it. One possible way is that the weakness weakens pulls north. Then the high builds in. We will need to watch this.


If it get pass 30 to 32 north by tomarrow around 2pm then forget about it. Also to note is that convection going all the way down off the eastern sea board. That is rising air in front of the trough/weakness. That shows just how far south it is. The models do hint of turning this more east later on as the trough/weakens pulls away to the north. In which is more of a case of moving on the back side of the Azores ridge later as it moves pass 35/60.

[mike18xx]

The cyclone should fellow the back side of the weakness/trough to the north.

Loop that WV a little faster, and you'll see that the "nose" of the ridge has already poked over West Virginia and is heading quickly into North Carolina; blow-off from Carolina convection north of Franklin is already veering from east to south and southwest.

[hial2]

Mike, your forecast goes against every model and against everything that the forecasters say, but like Franklin (the forecaster, not the storm) said "It is Worth noting however...that some of the largest track errors
occur in high-shear scenarios such as this one." It appears that that they are cya-ing just in case your scenario is correct!

[sweetpea]

If it did loop any ideas where it would go?

[wxwatcher91]

If it did loop any ideas where it would go?

somewhere between Miami and Boston???

[djones65]

Actually, there are some models which forecast Franklin to loop north of the Bahamas... The BAM Medium and BAM Deep models forecast it to move east northeast for next 18 hours and stall briefly as it drifts south and southwest and then west towards the northwest Bahamas and east-central Fl coast. In addition, the GFS run from 06Z shows Franklin getting sheared with the low level swirl accelerating northeast while the mid level circulation meanders near 30N 73W before turning back west southwest.
So therefore it is incorrect to say that none of the models forecast anything like what Mike was suggesting.
http://twister.sbs.ohio-state.edu/text/ ... ic/models/
Then click on the "05072312" link at the bottom of the page and it will list the forecast plots for the BAM models.
http://www.hpc.ncep.noaa.gov/discussions/pmdhmd.html
If you read in the second paragraph it describes the 06Z GFS forecast for Franklin.

[mike18xx]

Mike, your forecast goes against every model and against everything that the forecasters say, but like Franklin (the forecaster, not the storm) said "It is Worth noting however...that some of the largest track errors
occur in high-shear scenarios such as this one."

...because models are poor at predicting sheared and left-behind LLCCs (which then track SW/W behind the front as the ridge builds); they also, IMO, do not handle fujiwara situations between TCs and ULLs very well.

Back to the situation at hand: Check out the loop again, and note the Yucatan anticyclone becoming more circular; this will allow the Florida ULL, invigorated by the approaching front, to drop south into the "pocket" setting up. Franklin, fujiwaring, should go along for the ride.

[mike18xx]

One factor that was not present when I started this thread was all the convection now associated with Franklin -- and a storm with more "vertical presence" is likelier to be dragged east than a low-level swirl.

[Nimbus]

The convection is starting to curl back west all the way up to south Carolina now.

Wonder if the models have Franklin initialized correctly?

[hial2]

Mike said "this will allow the Florida ULL, invigorated by the approaching front, to drop south into the "pocket" setting up. Franklin, fujiwaring, should go along for the ride."

I just checked the IR loop, and the Fl ULL appears to be dropping south..so far, so good for your prediction...

[mike18xx]

The models are in stitches over this thing:

TROPICAL STORM FRANKLIN DISCUSSION NUMBER 9
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
11 AM EDT SAT JUL 23 2005

THE INITIAL MOTION ESTIMATE IS 055/08...BASED ON THE PAST 9 HOURS OF
RECON FIXES. THE CENTER OF FRANKLIN IS LOCATED NEAR THE NORTHWEST
PORTION OF THE COLD CDO CLOUD SHIELD AND IS SHOWING SIGNS OF
BECOMING BETTER ORGANIZED IN SATELLITE IMAGERY THAN WHAT MOST OF
THE GLOBAL MODELS HAVE BEEN INDICATING. THE STRONG SHORTWAVE NOW
APPROACHING THE U.S. EAST COAST HAS MOST OF ITS ENERGY FROM NORTH
CAROLINA NORTHWARD...WITH ONLY 5-10 WEST-NORTHWESTERLY MID-LEVEL
FLOW INDICATED SOUTH OF THE CAROLINAS. MOST OF THE MODEL GUIDANCE
...EXCLUDING THE MUCH FASTER GFS AND GFDL MODELS...NOW SLOWS DOWN
FRANKLIN THROUGH 72 HOURS AND EITHER DISSIPATED THE CYCLONE OR
WAITS FOR ANOTHER SHORTWAVE TROUGH TO PICK UP THE CYCLONE AND
ACCELERATE IT QUICKLY TO THE NORTHEAST. JUST ONE PROBLEM...ALL OF
THE MODELS...TO SOME DEGREE...MOVE THE MID-LEVEL CIRCULATION SLOWLY
BACK TO THE SOUTH AND SOUTHWEST AFTER 72 HOURS. THIS SCENARIO IS
SIMILAR TO THE MEDIUM AND DEEP BAM MODELS. GIVEN THAT FRANKLIN IS
CURRENTLY SOUTH OF AND SLOWER THAN ALL OF THE NHC MODEL GUIDANCE
FROM 06Z...AND THAT ALL OF THE MODELS FORECAST THE MID-LEVEL FLOW
TO BECOME NORTHWEST TO NORTHERLY BY 72 HOURS...THE OFFICIAL TRACK
HAS BEEN SHIFTED TO THE RIGHT...OR SOUTH...OF AND A LITTLE SLOWER
THAN THE PREVIOUS FORECAST. THIS TRACK IS CONSISTENT WITH THE GUNS
MODEL CONSENSUS.

[Sanibel]

As soon as I saw the visible loop I came in to post exactly that.

I don't know if it's looping - maybe it's not, but it is surely moving slowly enough that it may miss its connections.


You should be careful about Franklin Fujiwaring off a ULL. If Franklin reacts to a ULL it will be incidental instead of controlling. The dominating steering feature is the Atlantic synoptic, not the ULL. (I thought the Florida feature was a tongue of high pressure) (It's probably a surface High)

[WeatherEmperor]

and now we play the waiting game....

<RICKY>

[Sanibel]

HELLO!


He's definitely due east right now and probably entering a cyclonic loop...

[jhamps10]

HELLO!


He's definitely due east right now and probably entering a cyclonic loop...

I would have to agree on that. The NHC had that in the very 1st forecast.

[Stratusxpeye]

so if im interperting it all right you guys are saying it will most likely loop? and effect land or just loop back out to see?

[mike18xx]

You should be careful about Franklin Fujiwaring off a ULL. If Franklin reacts to a ULL it will be incidental instead of controlling. The dominating steering feature is the Atlantic synoptic, not the ULL.

Normally, you'd think so, but as I observe Franklin, it's not being dragged up by the zippin'-along northward-moving flow (on the west side of the Bermuda high) just to its east; instead, the TS is just sitting where it is and spitting off successions of outflow boundries to the northeast. Meanwhile, the surface front has cleared the Carolina outer-banks, and winds are now out of the north and northeast there.

(I thought the Florida feature was a tongue of high pressure) (It's probably a surface High)

Well, you can have surface high pressure associated with an upper-low (the feature clearly is an ULL on WV).

Predictaguesstimate: The short-wave trough (and associated mid-level easterlies) will rapidly exit the east-coast, leaving a lingering horizontally-draped front off-shore; this front will quickly modify and wash out (it has already done so on land, where it can no longer be discerned in the southeastern states. In approx 24-36hrs, the front will be completely dissolved, leaving behind Franklin on the south side of a strengthening ridge; the is an good chance Franklin will be a hurricane by this time. In about two days, west-southwest-ward movement should take Franklin near or over Florida.

[jhamps10]

so if im interperting it all right you guys are saying it will most likely loop? and effect land or just loop back out to see?

I think it will, as much as I hate to say this, espically since my neighbor just left for there on vacation , it will loop around and effect Florida.

[hurricanefreak1988]

Sheesh, the tropics just need to leave Florida alone. Come give us a visit, Franklin. My hometown hasn't seen some real hurricane action since Floyd.