Dr. Jeff Masters' WunderBlog

WAG time again.

The ULL or TUTT Low (Tropical Upper Tropospheric Trough) should not be much of a factor in the future movement of Dean.

If you believe the non-tropical models this TUTT is really evident only at the 300mb level and above (approx 30,000 ft) and would not exert much of a steering influence at that height.
If anything, it may add some VWS (vertical wind shear) into the equation and limit or reduce storm intensity farther down the track.

Then again, it could aid outflow across the top of the storm as well.

That said, we're down to a persistence track and the model consensus appears logical.

Still see some model inconsistencies in the location of the western periphery of the ridge next week so the possibility of some small changes to the right of consensus could occur.
OR
just might be my evil-inner-wishcaster-self rearing its ugly head

(nuttin like a 2-3 day adrenaline rush just prior to and during a landfall in your neck of the woods)

Course the 2-3 or more weeks of primitve conditions that follow really suck.



I had guessed mid-upper TX coast on Friday next a couple of days ago as landfall/time.

The ULL over Fla seems to be on track..a slow wastward movement...thats wht the NHC holds to their forecast.

LAWXguy, If that trend continues, it would put the eye within 70 mi of Key West.

No one living on the Gulf Coast is going to make a decision based on a 5 day computer model.....if you don't like here its all theoretical.

HH just went through the eye

150530 1546N 06836W 6962 02749 9567 +118 +118 143135 138 110 008 00

max flight winds found 138 kts.

This movement could be good for Jamaica, not so great for DR, Haiti, and Cuba. It is pretty well N of the forecast points, and still moving that way WNW with a little more N in it.

Drak - good advice about not paying attention to the wobbles. Many on here make it seem like the models can't even predict what will happen in the next 12 hours...and that the NHC mets (some of the best in the world) can't figure it out either!! lol.

Now having said that...I remember models and NHC keeping Charley moving towards Tampa...and we clearly saw the bend away from the track that put him right into Punta Gorda.

Recon just went through the eye...extrapolated 924mb.
Oddly enough...the SFMR only had 115kt surface winds on the NE eyewall.

Dan....that is the highest 10 second wind,so essentially a flight level gust of 138,not a sustained wind.

i think we are looking at an allen analogue - http://www.nhc.noaa.gov/archive/storm_wallets/atlantic/atl1980-prelim/allen/prelim02.gif
i would like to see the september analogues and cat 1 and 2s in the area as well, but given the atmospheric conditions and upper level currents i'm hoping it is like allen. hits kingsville where nobody lives and looses steam before hitting

Conversion table for
knots to miles per hour
KTS to MPH

5 Knots = 5.8 MPH
10 Knots = 11.5 MPH
15 Knots = 17.3 MPH
20 Knots = 23.0 MPH
25 Knots = 28.8 MPH
30 Knots = 34.6 MPH
35 Knots = 40.3 MPH
40 Knots = 46.1 MPH
45 Knots = 51.8 MPH
50 Knots = 57.6 MPH
55 Knots = 63.4 MPH
60 Knots = 69.1 MPH
65 Knots = 74.9 MPH
70 Knots = 80.6 MPH
75 Knots = 86.4 MPH
80 Knots = 92.2 MPH
85 Knots = 97.9 MPH
90 Knots = 103.7 MPH
95 Knots = 109.4 MPH
100 Knots = 115.2 MPH
105 Knots = 121.0 MPH
110 Knots = 126.7 MPH
115 Knots = 132.5 MPH
120 Knots = 138.2 MPH
125 Knots = 144.0 MPH
130 Knots = 149.8 MPH
135 Knots = 155.5 MPH
140 Knots = 161.3 MPH
145 Knots = 167.0 MPH
150 Knots = 172.8 MPH

Thanks BtnTx.

I made the decision to hang out in Corpus Christi for Erin. I asked here and everyone who responded pretty much agreed.

Doug put me on the exact coordinates at landfall since I was busy driving.

I'll have to be careful about getting too close to the beach next week for Dean when it makes landfall. Had a storm the size of Dean hit Padre Island on Thursday, that entire part of the island would have been underwater.

I think I'll stay somewhat inland for Dean.

Just from past experience...........I seem to be picking up on a unsettleness from all the communication processes(NHC, TWC,etc)....I know we are dealing with a major hurricane but it just seems like there is alot of uncertainty behind the scenes......just something that i am sensing.....I just have a feeling that theres more to it then meets the eye.........

Is the change to more WNW on time with the models? It had been moving almost due W. The timing and degree and these changes is what I'm concentrating on.

SJ, Are those concentric eye walls on the PR radar? Thanks

I noticed a more northward jog with Dean. Is this a temporary job or one that stay permanent and could make go further east toward La.?

I still think Florida is safe. I don't recall any models pointing to Florida. It would literally have to cut at least 90 degrees to hit us from the SW point of the GOM.

wbk, that would be somewhat expected if Dean is starting to under go a EWRC. There is usually some weakening associated with that.

Morning all - just popped in for a moment - busy day...

What's the scoop? Is the current motion a change in direction, or some sort of wobble? With ULLs out of range to the NE and NW of the storm, I assume that they are not affecting it.

Just looked at the dropsonde in the eye...had 930mb with 8kt surface winds.So surface minimum pressure's around 927-929.

So far this season, these CSU guys have pretty well called it when formation probability spikes. The last 2 spikes resulted in systems and we are now exceeding the probability present when the previous systems formed.

atmoaggie....CSU doesn't make that map.

you can also use google calc for knots in mph - search "137 knots in mph" or whatever and it'll tell you - google is a good thing..

actually steve lyons said that if they moved the track at all they would probalby move it further sout. hard to believe for me but who knows.

I just have a feeling that theres more to it then meets the eye.........

Pun intended.

I don't jump at "wobbles". This has been constant all morning (at least 6 hours).

he north of the track right now..its probably just a wobble

Agreed SJ, WNW and N of track slightly. The GFS model takes this track and still parks it in Mexico. Interesting to see the spewing of 'atmosphere' off west coast Africa into CATL in a WNW direction. Almost looks like it is 'pushing' the CATL ULL toward the Dean ULH and in turn Dean ULH pushing ULL all westward. Just my untraind eye watching the force of that African wave that evaporated. I don't see s surface circ any more with the LB from yesterday now aorund 17N 38W. I think it fell apart.

Posted By: weatherboykris at 3:25 PM GMT on August 18, 2007.

atmoaggie....CSU doesn't make that map.

right, RAMMB in CIRA at CSU, staffed by CSU folks, sorry.

08er, yu have a link to the radar?

BuffaloSnow77....TWC had also hedged their bets with buying up stocks for roofers in south Texas.

wow a 20-25% formation probability in 24 hours...

Yes SJ,

Link

I believe has found a weakness for the time being.... How long do ya'll think it will last??

I'm not sure how long it will last.... BUT if it lasts up until 2pm this afternoon, I'm afraid some of the models may shift out of Mexico for the next model run...

DO ya'll think that's possible?

No.........I am talking about the potential U.S. Landfall possibities..........The U.S. government doesnt want to spook anyone if there is no need.......Still, alot of uncertainty.......What if Dean does one of its jogs right before hitting the Yucatan? Does it stay between cat 4 and cat 5 and for how long???????

Why all the wobble talk? In the almost last 6 hours it's starting moving more WNW. The coordinates bare this out. The biggest move north in the life of this storm.

Just got back on here... Anybody have any updates as to which way this thing may (or may not) turn? I'm hearing about a WNW or N jog. Haven't had a chance to check maps.

guru, he went from S of track to N of track, and this has been going on for quite some time.

Here is my current analysis on Hurricane Dean as of the latest advisory. Based on the latest satellite imagery, you can clearly see the WNW to almost NW motion of the hurricane that has been maintained for at least the past 6 to 8 hours. It is no longer a wobble in my opinion, but a change in course direction. But, of course, this hurricane can change back to a due west course like it was last night.

Now, we have all been watching a critical indicator for the future path of this storm in the ULL over South Florida. It appears to be migrating off the SW towards the Yucatan Channel. If this is the case, it could act as a "deflector shield" for the Yucatan and Southern Gulf and spare them of the worst. The big question is where is the ULL going to be positioned when Dean approaches the ULL? If the ULL is directly in the Yucatan Channel, it could take an extreme turn towards the north or even NNE which would create a whole new ballgame. If the ULL is located in the Bay of Campeche, then the Yucatan would get a direct hit and would be spun off into the northern GOM. If the ULL is located on the western tip of Cuba or the extreme western Florida Straits, it would get sucked up like a vaccuum into Florida. But, if the ULL is in the center of the GOM, it will have little effect on the storm.

I will not predict the future path of this hurricane as there is a great degree of uncertainty involved with the environment surrounding the storm. But, nonetheless, it will be very interesting ot see the impact the ULL makes in the future path of the storm.

What are your thoughts on my analysis?

LaWxGuy - anything's possible at that range. I wouldn't put any stock in any model beyond 72 - 96 hours. Pay attention to the regional conditions - they'll usually tip you off more accurately...

the RUC which is a very short term model is pushing the ULL farther south than the last GFS run. the closer this low gets to the passage between the yucatan and cuba, and the stronger it gets the more it is going to tug towards the gulf. this appears to be a pretty significant change to the status quo.

the satalite just made a adjustment move noth northwest.
models not adjusted to that. just happened now

well if i draw a line it looks really close to Port-au-Prince then Guantánamo

Trochoidal wobbles (or cycloidal oscillations) happen when the eye drifts slightly off-center with respect to the circulation and thus "orbits" the center. It is most common in the decaying stage of a pinhole eye. Wilma in 2005 gave a lovely example--and it was amusing to see how it confused those who did not see what was happening. If you track a storm by eye position, it can drive you nuts.

CCHS - agree on all points (for the most part).

Dean is moving a bit faster than the ULL. So, there's no doubt that at some point, there will be interaction.

SJ, Drak - I asked last night and didn't get any answer - any idea how far away from the ULL that Dean's motion can be effected by it?

cchs... very interesting... I think you have explained this the best I've ever heard it explained so far on this blog...

Great uncertainty is the key... ESPECIALLY if Dean's WNW to NW motion continues the rest of the day today... I believe that would prove that Dean is noticing and reacting to the ULL over Florida....

08er, I could not tell a lot from the radar, but from current sat, and MIMIC imagery that is 3hrs old, it looks that way to me.

If any of you have not seen MIMIC imagery, you really need to check it out. A type of Microwave morphed imagery. Really cool. Only problem is it only updates every 6-12hrs I think.