Extratropical Irene Advisories

[cycloneye]

BULLETIN
TROPICAL DEPRESSION IRENE ADVISORY NUMBER 21
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
ISSUED BY THE HYDROMETEOROLOGICAL PREDICTION CENTER CAMP SPRINGS MD
5 PM EDT TUE AUG 09 2005

...IRENE BECOMING BETTER ORGANIZED...

AT 5 PM EDT...2100Z...THE CENTER OF TROPICAL DEPRESSION
IRENE WAS LOCATED NEAR LATITUDE 22.6 NORTH...LONGITUDE 54.4 WEST OR
ABOUT 925 MILES...1485 KM...SOUTHEAST OF BERMUDA.

THE DEPRESSION IS MOVING TOWARD THE WEST AT 9 MPH
...15 KM/HR...AND THIS MOTION IS EXPECTED TO CONTINUE
FOR THE NEXT 24 HOURS.

MAXIMUM SUSTAINED WINDS ARE NEAR 35 MPH... 55 KM/HR...WITH HIGHER
GUSTS. SOME GRADUAL INCREASE IN STRENGTH IS LIKELY DURING THE NEXT
24 HOURS.

ESTIMATED MINIMUM CENTRAL PRESSURE IS 1008 MB...29.77 INCHES.

REPEATING THE 5 PM EDT POSITION...22.6 N... 54.4 W. MOVEMENT
TOWARD...WEST AT 9 MPH. MAXIMUM SUSTAINED WINDS... 35 MPH. MINIMUM
CENTRAL PRESSURE...1008 MB.

THE NEXT ADVISORY WILL BE ISSUED BY THE NATIONAL
HURRICANE CENTER AT 11 PM EDT.

FORECASTER KIMBERLAIN

[gkrangers]

So NHC is back at 11.

[yoda]

So NHC is back at 11.

Yup... probably was just a dry run with HPC.

[cycloneye]

So NHC is back at 11.

Yep NHC takes over at 11 and I know that they are much more rapid in terms of putting out the advisorie products.

[cycloneye]

WTNT44 KNHC 092100
TCDAT4
TROPICAL DEPRESSION IRENE DISCUSSION NUMBER 21
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
ISSUED BY THE HYDROMETEOROLOGICAL PREDICTION CENTER CAMP SPRINGS MD
5 PM EDT TUE AUG 09 2005

VISIBLE SATELLITE IMAGERY THIS AFTERNOON INDICATES THAT IRENE
APPEARS TO BE UNDERGOING A METAMORPHOSIS. THE CLOUD STRUCTURE
ASSOCIATED WITH THE TROPICAL CYCLONE IS GRADUALLY BECOMING MORE
SYMMETRIC...CIRRUS OUTFLOW EMANATING FROM IT IS MORE DIVERGENT
...AND THERE ARE OCCASIONAL SIGNS OF BANDING. COMPARED TO 24 HOURS
EARLIER...IRENE IS CERTAINLY BETTER ORGANIZED. ALL SATELLITE
AGENCIES EXCEPT AFWA ARRIVED AT DVORAK CLASSIFICATIONS BELOW
TROPICAL STORM STRENGTH. ON THIS BASIS...IRENE IS KEPT A TROPICAL
DEPRESSION AT THIS TIME.

THERE WERE SOME DIFFERENCES CONCERNING THE INITIAL POSITION OF THE
DEPRESSION...BUT POSITION ESTIMATES YIELD A SIX HOUR MOTION OF
280/8. IN THE SHORT TERM...IRENE MAY NOT REGAIN ENOUGH
ORGANIZATION TO BE VERTICALLY COUPLED. THUS IT WILL LIKELY ASSUME
A HEADING AND SPEED MORE COMPARABLE WITH THE LOWER LEVEL FLOW.
THEREAFTER...THE FORECAST BECOMES MORE PROBLEMATIC. OVER THE NEXT
FEW DAYS...THE 12Z ECWMF AND NOGAPS MODELS INDICATE THAT IRENE WILL
MOVE UNDERNEATH A MID LEVEL RIDGE LYING OVER THE WESTERN ATLANTIC
...WHICH SHOULD KEEP THE STORM ON A MORE WESTERLY TRACK. ON THE
OTHER HAND...THE 12Z UKMET SHOWS A SHORTWAVE TROF ERODING THE RIDGE
ENOUGH TO CAUSE A TURN TOWARD THE NORTH AROUND 72 HOURS.

THE FUTURE TRACK OF IRENE DEPENDS VERY MUCH ON THE EVOLVING LONGWAVE
PATTERN IN THE MID LATITUDES LATER ON IN THE FORECAST.
SPECIFICALLY...A BLOCKING RIDGE OVER ALASKA AND AN AMPLIFICATION OF
A DOWNSTREAM TROF OVER THE NORTH CENTRAL/NORTHWESTERN U.S. WILL
DETERMINE HOW ROBUST THE WESTERN ATLANTIC RIDGE WILL BE AND HOW
LONG IT STAYS IN PLACE. AT THIS TIME...GIVEN THE GOOD AGREEMENT ON
THE LONGWAVE PATTERN IN THE NCEP AND ECWMF ENSEMBLE MEAN SOLUTIONS
WHICH DEPICT A CLOSED ANTICYCLONE TO FORM OVER THE WESTERN ATLANTIC
AT THAT RANGE...THE TRACK OF IRENE HAS BEEN SHIFTED FARTHER SOUTH
AND WEST.

AFTER SEVERAL DAYS OF ENDURING MODERATE VERTICAL WIND SHEAR IN
ASSOCIATION WITH A SHARP UPPER TROF TO ITS NORTHEAST...MODELS
GENERALLY AGREE THAT IRENE WILL ENTER A MORE FAVORABLE ENVIRONMENT
FOR DEVELOPMENT. THEY FORECAST THE SHEAR VECTOR OVER THE
DEPRESSION TO SHIFT FROM A NORTHWESTERLY TO EAST AND BECOME WEAKER
WITHIN 24 TO 36 HOURS. AFTER THIS TIME...IRENES POSITION SOUTH OF
THE RIDGE OVER THE WESTERN ATLANTIC SHOULD FAVOR A GENERAL
INTENSIFICATION. THE FORECAST INTENSIFICATION IS VERY MUCH IN LINE
WITH THE SHIPS MODEL THROUGH THE PERIOD.


FORECASTER KIMBERLAIN


FORECAST POSITIONS AND MAX WINDS

INITIAL 09/2100Z 22.6N 54.4W 30 KT
12HR VT 10/0600Z 22.7N 55.7W 30 KT
24HR VT 10/1800Z 23.4N 57.7W 35 KT
36HR VT 11/0600Z 24.7N 59.5W 40 KT
48HR VT 11/1800Z 25.7N 60.5W 45 KT
72HR VT 12/1800Z 27.0N 62.6W 50 KT
96HR VT 13/1800Z 28.0N 65.4W 55 KT
120HR VT 14/1800Z 29.0N 68.5W 60 KT

[deltadog03]

westward bound we go...

[Ivanhater]

westward ho!!!!!

[Derek Ortt]

becoming better organized? I'm sorry but this statement is absurred. Dry air has made the atmosphere more stable than previously. Yes, it is almost certain to intensify into a TS, with an outside chance at a cane, but the process has not yet begun

[gatorcane]

here we go....watch out FL and the East coast

[cycloneye]

[Brent]

[Thunder44]

becoming better organized? I'm sorry but this statement is absurred. Dry air has made the atmosphere more stable than previously. Yes, it is almost certain to intensify into a TS, with an outside chance at a cane, but the process has not yet begun

This is from the discussion:

COMPARED TO 24 HOURS
EARLIER...IRENE IS CERTAINLY BETTER ORGANIZED.

How did Irene look at this time yesterday?

[Derek Ortt]

from a LLC vantagepoint, it was better organized yesterday, to be honest.

As I said, I fully expect intensification... just aren't seeing signs of it yet

[deltadog03]

pretty crappy...she had a very nice LLC though

[mvtrucking]

Just a guess nothing more. It stays west across southern Florida (Maybe the FS) and into the GOM.

[gkrangers]

Just a guess nothing more. It stays west across southern Florida (Maybe the FS) and into the GOM.

No.

[Hyperstorm]

from a LLC vantagepoint, it was better organized yesterday, to be honest.

As I said, I fully expect intensification... just aren't seeing signs of it yet

I actually think it is better organized today. While it is NOT the best organized tropical depression, the system has gone through important structural changes today. It seems the MLC that I was seeing earlier will become the dominant circulation as the old center can no longer be tracked.

I blame the lack of strong convection to the diurnal minimum we're currently going through, plus the fact that the MLC hasn't reached the surface yet. Therefore, there is not enough forcing going on. I expect the system to re-fire strong convection starting tonight into tomorrow morning. Only then, will we see steady intensification.

Today was a head start...

[johngaltfla]

Looking at those model tracks, I think I'll just go play Roulette rather than venture a guess at what she'll do. Because if any of the more southern and westward ones bear out, this could be a very rainy weekend or Monday coming up. Until this sucker strengthens, I think all bets are off.....

[Brent]

Because if any of the more southern and westward ones bear out, this could be a very rainy weekend or Monday coming up. Until this sucker strengthens, I think all bets are off.....

Actually... it'll be next Tuesday-Wednesday before it gets close. The Sunday Afternoon position is still east of 70 W.

[Cookiely]

I like this word " METAMORPHOSIS". First thing that comes to mind is magic. Second thing that comes to mind is a woman is in constant flux. What's the moon doing at present? You do have to hand it to Irene because she has had a difficult journey just to get this far. Its amazing she has survived at all.