berrywr
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Loc: Opelika, AL
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I'm a little surprised you didn't factor the longwave pattern into Irene. As early as yesterday's 06Z run; not current 06Z run mentioned the possibility of strong ridging over Alaska which would induce a deeper longwave trof over the NW to Mid US thus induce stronger ridging over the W ATLC which it appears to be what's in play, though the new run doesn't indicate as strong a trof in the mid US, iit continues to amplify the SE ridge through 120 hours. Thus far the 06Z is the consensus model of choice with current features. Irene continues to move due west as of this typing and appears on satellite to be quite symmetrical and thunderstorms are firing to her SW and N with very cold tops. Whether that continues, remains to be seen, but it does appear it's becoming more organized early this morning. I think if the evolution of the longwave pattern pans out, Irene should continue on a more west and southerly track around the perphery of the ridge.
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Sincerely,
Bill Berry
"Survived Trigonometry and Calculus I"
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berrywr
Weather Analyst
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Right now, at best you're talking a good 6 days out assuming a Florida landfall would be in play at that time! No model at this time is hinting at that, though the longwave pattern is hinting at a more west and south track than currently projected. Right now, there's just no way to know. Possible? Yes; nothing is impossible this far out, but it would be foolish to even speculate.
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Sincerely,
Bill Berry
"Survived Trigonometry and Calculus I"
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berrywr
Weather Analyst
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Yes! In a hostile environment, it's reasonable to speculate, but thus far Irene has persevered through worse and she isn't looking too bad on satellite this morning...trudging west.
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Sincerely,
Bill Berry
"Survived Trigonometry and Calculus I"
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berrywr
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The link you're referring to what you see are called streamlines; it's common in tropical latitudes to use them because you don't see what we refer to in the met biz as dynamic lows and ridges which exist by baroclinic processes; differences between cold and hot in the atmosphere. In the tropics winds are usually very light and pressures don't vary too much at the surface. In the upper air, think of 850mb as 5,000 feet, 700 mb as 10,000 feet, 500 mb as 18,000 feet, 300mb as 30,000 feet. When you look at the particular chart you're looking at; there is no shear to speak of at 850 to 700mbs and you will note the streamlines are much more in line with the low and mid latitude flow below 10,000 feet which isn't indicative of a "developed" tropical system. Being that this system is relatively shallow, it continues to be steered by the low level winds this chart indicates. Satellite photos will also aid you in determining that too. Water vapor doesn't help unless you're talking about a vertically coupled system; that is the storm is stacked from bottom to top, and if so, it's steering is done by the flow at 500mbs and up. To get a picture of shear over the storm you need the main link: http://cimss.ssec.wisc.edu/tropic/real-time/atlantic/winds/winds.html Then go to Wind Shear http://cimss.ssec.wisc.edu/tropic/real-time/atlantic/winds/wg8shr.html When talks about shear, this is the chart they're looking at, now when they mention shear below the outflow level, you have to look for something higher, like 400 mbs. These charts are vital in determining the environment these cyclones are in, and as you see as of this typing, the storm is in a fairly low shear environment now at that level, so if you go lower and look at http://cimss.ssec.wisc.edu/tropic/real-time/atlantic/winds/wg8midshr.html which is mid level shear, you will note the northerly component which has been referring to and as you see, it's not low and it's not high, but more than likely just high enough to keep the storm somewhat decoupled at that particular column thus it remains a tropical depression at this time. To look at the satellite presentation currently, it appears it's winning the battle of the environment and as of this typing looks about as good as it's been in the past day or so, so don't be surprised if you might see an upgrade on the 5 am advisory, though is pretty conservative when it comes to continuity; very rare will you see them radically leap in one advisory, unless a recon mission justifies it. I suspect you'll see a shift west and south but not too radical on thie next advisory.
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Sincerely,
Bill Berry
"Survived Trigonometry and Calculus I"
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berrywr
Weather Analyst
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Loc: Opelika, AL
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Anything beyond 120 hours is simply speculation....If there is one thing I've learned it's you can't sit here and watch this thing in little increments, with every forecast in the future dependent among moment to moment events with a storm. Think about it? 5 days out! That's 20 advisories, 10 model runs and several recon missions and a few NOAA runs sampling the atmosphere ahead of the system. As this storm draws closer is when the atmosphere is sampled over and over for the littlest change; not 5 or 6 days out. Moderators need to pay heed to this too. You cannot moment to moment forecast 5 or 6 or 7 days out; you can't do it. There isn't enough upper air data out there to get a good fix on this, thus with each model run things change; currently the UKMET is the outlier with it's turn to the north at days 3, 4 and 5. That too will change. It always does!
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Sincerely,
Bill Berry
"Survived Trigonometry and Calculus I"
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berrywr
Weather Analyst
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As I just a moment ago posted...you can't moment to moment forecast, it's own thing to short term forecast or what they call NOW forecasting; it's another when it's current; that isn't forecasting; that's observing. will not sample the atmosphere religiously until it gets within the 120 hour window, which I suspect will be sometime on late Wednesday beginning with the 00Z run on the 11th or maybe later. And once that data is inputted into the model runs, then a clearer picture will begin to reveal itself as to the future track. I also said this earlier, the evolution of the longwave pattern will play a role in this storms' future track and the strength of the ridge to it's NW and if anyone has ever read the extended forecast discussion; it's a headache when you look at the models and what they're telling you; this time it's a ridge or rex block over Alaska that will determine where this baby eventually goes; hard to believe that something so far away has those kinds of effects, but like squeezing a balloon, that's exactly what happens when you take into effect the downstream affects.
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Sincerely,
Bill Berry
"Survived Trigonometry and Calculus I"
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danielw
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Loc: Hattiesburg,MS (31.3N 89.3W)
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TROPICAL DEPRESSION IRENE DISCUSSION NUMBER 23
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
5 AM EDT WED AUG 10 2005 (edited~danielw)
THERE IS LITTLE OR NO EVIDENCE THAT IRENE STILL HAS A CLOSED CIRCULATION.
AS NOTED IN THE PREVIOUS DISCUSSION...LAST NIGHT'S
QUIKSCAT AMBIGUITIES COULD NOT DEFINE A CENTER...AND THE LOW CLOUD LINES IN THE NIGHT-VIS IMAGERY ALSO SUGGEST THAT IRENE IS ELONGATING AND LIKELY HAS DEGENERATED INTO AN OPEN TROUGH.
IF THERE IS A CENTER...IT IS PROBABLY SOUTH OF THE CURRENT ADVISORY POSITION IN THE DEEP CONVECTION SOUTH OF 22N. GIVEN THE UNCERTAINTIES HOWEVER...IT IS PRUDENT TO WAIT FOR VISIBLE IMAGERY BEFORE
DISSIPATING OR RELOCATING THE CYCLONE.
THE INITIAL INTENSITY IS LOWERED TO 25 KT BASED ON THE MOST RECENT QUIKSCAT DATA AND THE PRESENT LACK OF ORGANIZATION OF THE SYSTEM.
http://www.nhc.noaa.gov/text/refresh/MIATCDAT4+shtml/100836.shtml
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OrlandoDan
Weather Master
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Loc: Longwood, FL
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Irene's Outflow is looking more impressive.
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Keith (1988), Charley (2004), Frances (2004) , Jeanne (2004), Fay (2008), Mathew (2016), Irma (2017), Dorian (2019)
Personal Weather Station: https://www.wunderground.com/dashboard/pws/KFLLONGW67
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rmbjoe1954
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Loc: Port Saint Lucie, Florida, USA
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Agreed. I believe we will see a flare up today with a closed circulation. It is approaching warmer waters- and I don't see sheer being a factor.
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________2023 Forecast: 20/10/5________
There is little chance that meteorologists can solve the mysteries of weather until they gain an understanding of the mutual attraction of rain and weekends. ~Arnot Sheppard
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OrlandoDan
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Loc: Longwood, FL
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Sure looks like there is a broad, closed, wobbling center to me.
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Steve H1
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Loc: Palm Bay FL USA
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Actually, Irene's appearance is improving this morning, with convection building around the center and improved outflow/symmetry. Interesting that the models are taking hertoward the WNW, and further north than last nights run, at least from the tropical models. Much speculation on the building of a ridge along the east coast.....have a feeling the models will change again....they usually do! Cheers!!
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Random Chaos
Weather Analyst
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Loc: Maryland
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Yeah, it is definately looking healthier this morning. I'm seeing stronger convection and what looks like banding starting to pop up.
Got a quicky question about SSD: On their storm floaters, where does it tell you which floater is on which storm without having to compare the graphic to some other site? Thanks!
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ftlaudbob
Storm Chaser
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Loc: Valladolid,Mx
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The bottom line is,She is still moving west.The last few days they keep on saying she will turn more north,she has not,not even a little bit.Everyday I look at the forcast map and it has it curving north,well,she is not listening to them.
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Survived: 10 hurricanes in Rhode Island,Florida and the Yucatan of Mexico .
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nl
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is that the high ridge coming in north of jacksonville? 
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VolusiaMike
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Little hard to tell on the visibles yet, but does that look like a center trying to develop at about 23/57 to anyone else?
If so, the convection is really building to the SW...
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Fletch
Weather Guru
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Loc: Ft. Lauderdale, Florida
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Quote:
The bottom line is,She is still moving west.The last few days they keep on saying she will turn more north,she has not,not even a little bit.Everyday I look at the forcast map and it has it curving north,well,she is not listening to them.
You're right, but I think its because the system has been so weak. This thing is like Randle "Tex" Cobb in a fight. It keeps getting the crap beat out of it but just won't go down. If the current organization keeps up, we'll probably start to see a more WNW motion later today.
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Irwin M. Fletcher
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ftlaudbob
Storm Chaser
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Loc: Valladolid,Mx
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Irene has survived alot,and now she will be moving into warm water with little or no shear.I am at 26N and 80.1W Irene is at 22.4N and 57.3W and heading due west.Thats what I care about.
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Survived: 10 hurricanes in Rhode Island,Florida and the Yucatan of Mexico .
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meto
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it is only at 22 latitude and it is moving w or even wsw. if ridge builds over it. it will not be able to recurve.
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Wxwatcher2
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If we were talking hurricane here I'd be worried but Irene is an extremely weak depression and at best if it does come toward South Florida, it would mainly be a rain event. True, if it continues West over warmer Bahamian waters than possibly it could strenghten. I don't see any reason at this time to even be concerned other than for the sake of tracking another storm.
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rmbjoe1954
Weather Master
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Loc: Port Saint Lucie, Florida, USA
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If TD irene is moving WSW than could she be feeling the affects of the ridge already?
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________2023 Forecast: 20/10/5________
There is little chance that meteorologists can solve the mysteries of weather until they gain an understanding of the mutual attraction of rain and weekends. ~Arnot Sheppard
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