ATL: KATIA - Post Tropical - Discussion

[bamajammer4eva]

From Joe Bastardi

back to the weather. pattern is reason Katia trends west. Typhoon hit in Japan supports big bermuda hi in week, blocks storm from going out Why? wpac weather forces changes in n hemisphere that "teleconnect"to western atlantic ridge, ohio valley trough

So basically he thinks Katia will make landfall somewhere in the East coast?

He's said this one would be a US threat since before it was even Classified. I would normally think he was out there with the teleconnection thing but the model trends are making him sound not so far fetched.

[Annie Oakley]

http://tropic.ssec.wisc.edu/real-time/windmain.php?&basin=atlantic&sat=wg8&prod=sht&zoom=&time=

Shear is almost nothing once past 57W.

Forgive my newbieness, but what does that indicate?

Meriland23, it is great you want to learn more about tropical weather etc. I applaud you! Here is a link you can check out when you have time.

https://www.meted.ucar.edu/index.php

from their site.........
"MetEd is a free collection of hundreds of training modules intended for the geoscience community. Whether you're an experienced meteorologist honing existing skills or a student looking for new topics of interest, we have something for you."

Like this

https://www.meted.ucar.edu/training_module.php?id=778

[RL3AO]

What's up with the UKMet? All day it's been trending toward Florida. Everything else is curving away. I thought it was supposed to be fairly accurate.

I think one of the UKMET's adjusted models was the most accurate last season.

[BigA]

The ULL looks like it's started to move out north during the last few hours, or at least the southern extent of its bad shear. Shear should still be a factor through tomorrow, but I believe it will lessen late tomorrow.

But shear is tricky. I'm not certain about the above statement.

[WeatherManwx79]

Not all hurricanes that get above the islands go out to sea. Just look at Fran's track in 1996.



Uploaded with ImageShack.us

[cycloneye]

BULLETIN
TROPICAL STORM KATIA ADVISORY NUMBER 16
NWS NATIONAL HURRICANE CENTER MIAMI FL AL122011
1100 PM AST THU SEP 01 2011

...KATIA CONTINUES OVER THE OPEN ATLANTIC...NO IMMEDIATE THREAT TO
LAND...


SUMMARY OF 1100 PM AST...0300 UTC...INFORMATION
-----------------------------------------------
LOCATION...16.7N 50.6W
ABOUT 830 MI...1335 KM E OF THE NORTHERN LEEWARD ISLANDS
MAXIMUM SUSTAINED WINDS...70 MPH...110 KM/H
PRESENT MOVEMENT...WNW OR 290 DEGREES AT 16 MPH...26 KM/H
MINIMUM CENTRAL PRESSURE...990 MB...29.23 INCHES


WATCHES AND WARNINGS
--------------------
THERE ARE NO COASTAL WATCHES OR WARNINGS IN EFFECT.


DISCUSSION AND 48-HOUR OUTLOOK
------------------------------
AT 1100 PM AST...0300 UTC...THE CENTER OF TROPICAL STORM KATIA WAS
LOCATED NEAR LATITUDE 16.7 NORTH...LONGITUDE 50.6 WEST. KATIA IS
MOVING TOWARD THE WEST-NORTHWEST NEAR 16 MPH...26 KM/H. THIS
GENERAL MOTION WITH A DECREASE IN FORWARD SPEED IS EXPECTED DURING
THE NEXT TWO DAYS. ON THE FORECAST TRACK...KATIA WILL CONTINUE TO
MOVE OVER THE OPEN ATLANTIC.

MAXIMUM SUSTAINED WINDS REMAIN NEAR 70 MPH...110 KM/H...WITH HIGHER
GUSTS. KATIA IS FORECAST TO REGAIN HURRICANE STRENGTH DURING THE
NEXT DAY OR SO.

TROPICAL STORM FORCE WINDS EXTEND OUTWARD UP TO 140 MILES...220 KM
FROM THE CENTER.

ESTIMATED MINIMUM CENTRAL PRESSURE IS 990 MB...29.23 INCHES.


HAZARDS AFFECTING LAND
----------------------
SURF...SWELLS GENERATED BY KATIA WILL BEGIN AFFECTING THE LESSER
ANTILLES BY LATE FRIDAY. THESE SWELLS ARE LIKELY TO CAUSE
LIFE-THREATENING SURF AND RIP CURRENT CONDITIONS. PLEASE CONSULT
PRODUCTS FROM YOUR LOCAL WEATHER OFFICE.


NEXT ADVISORY
-------------
NEXT COMPLETE ADVISORY...500 AM AST.

$$
FORECASTER AVILA



TROPICAL STORM KATIA DISCUSSION NUMBER 16
NWS NATIONAL HURRICANE CENTER MIAMI FL AL122011
1100 PM AST THU SEP 01 2011

MICROWAVE IMAGES AROUND 2245 UTC SHOWED THE CENTER OF KATIA ON THE
EDGE OF THE DEEP CONVECTION...BUT MORE RECENT SATELLITE IMAGES SHOW
AN INCREASE OF THE THUNDERSTORM ACTIVITY AND IT APPEARS THAT THE
CENTER IS AGAIN UNDER THE CANOPY. THE OUTFLOW HAS ALSO BECOME A
LITTLE BETTER DEFINED IN THE NORTHWEST QUADRANT. DVORAK T-NUMBERS
ONLY SUPPORT 55 KNOTS BUT GIVEN THAT THE CLOUD PATTERN IS A LITTLE
BETTER ORGANIZED THAN EARLIER THIS EVENING...THE INITIAL INTENSITY
IS KEPT AT 60 KNOTS. WATER VAPOR IMAGES STILL SHOW A SHARP
UPPER-TROUGH WITH ITS AXIS ALONG 56 DEGREES WEST LONGITUDE INDUCING
STRONG SOUTHWESTERLY SHEAR OVER KATIA. GLOBAL MODELS...MAINLY THE
GFS AND EVENTUALLY THE ECMWF INSIST ON WEAKENING THIS TROUGH AND
FORECAST A MORE FAVORABLE ENVIRONMENT FOR INTENSIFICATION IN A DAY
OR SO. THERE ARE NO SIGNS THAT THE TROUGH IS WEAKENING YET...AND
GIVEN THE CURRENT SHEAR...NO CHANGE IN STRENGTH IS INDICATED IN THE
NEXT 12 TO 18 HOURS. KATIA SHOULD BEGIN TO RE-INTENSIFY IN ABOUT 24
TO 36 HOURS AND BECOME A MAJOR HURRICANE IN A FEW DAYS ASSUMING
THAT THE ENVIRONMENT BECOMES LESS HOSTILE AS INDICATED BY GLOBAL
MODELS.

KATIA HAS SLOWED DOWN A LITTLE BIT AND IT APPEARS TO BE MOVING
TOWARD THE WEST-NORTHWEST OR 290 DEGREES AT 14 KNOTS AROUND THE
PERIPHERY OF THE SUBTROPICAL RIDGE. A TROUGH CURRENTLY LOCATED OVER
THE WESTERN ATLANTIC IS ERODING THE WESTERN SIDE OF THE SUBTROPICAL
RIDGE AND THIS WILL INDUCE A NORTHWESTERLY MOTION DURING THE NEXT
TWO TO THREE DAYS. HOWEVER...IN THE LONG RANGE...A STRONG MID-LEVEL
TROUGH IS FORECAST TO DEVELOP OVER THE GULF OF MEXICO AS THE
ATLANTIC SUBTROPICAL RIDGE BUILDS WESTWARD. THIS PATTERN SHOULD
FORCE KATIA ON A MORE WEST-NORTHWESTWARD MOTION BY THE END OF THE
FORECAST PERIOD AS INDICATED BY THE ECMWF AND THE GFS. THIS SMALL
BEND TO THE WEST-NORTHWEST IS REFLECTED IN THE OFFICIAL FORECAST.

ON THE FORECAST TRACK...KATIA WILL CONTINUE TO MOVE OVER OPEN WATER
DURING THE NEXT FIVE DAYS.


FORECAST POSITIONS AND MAX WINDS

INIT 02/0300Z 16.7N 50.6W 60 KT 70 MPH
12H 02/1200Z 17.5N 52.5W 60 KT 70 MPH
24H 03/0000Z 18.5N 54.0W 65 KT 75 MPH
36H 03/1200Z 19.5N 55.5W 75 KT 85 MPH
48H 04/0000Z 20.5N 57.0W 85 KT 100 MPH
72H 05/0000Z 22.5N 60.0W 95 KT 110 MPH
96H 06/0000Z 25.0N 63.5W 100 KT 115 MPH
120H 07/0000Z 26.5N 67.0W 105 KT 120 MPH

$$
FORECASTER AVILA

[gatorcane]

The nhc discussion indicates there is a wnw bend at the end of the forecast period.

The ECMWF and UKMET actually bends more wsw.

[AdamFirst]

[cycloneye]

http://img32.imageshack.us/img32/5917/023614w5nlsm.gif

Look at the bend to the left at the end.

[gatorcane]

I wonder if that bend west will be the start if a trend,,,,will it bend more?

Next set of model runs at 00z are going to be interesting,

[ozonepete]

Looks like a growing loss of confidence now that this will miss the CONUS. This line from the NHC discussion isn't comforting:

"A STRONG MID-LEVELTROUGH IS FORECAST TO DEVELOP OVER THE GULF OF MEXICO AS THE ATLANTIC SUBTROPICAL RIDGE BUILDS WESTWARD. THIS PATTERN SHOULD FORCE KATIA ON A MORE WEST-NORTHWESTWARD MOTION BY THE END OF THE FORECAST PERIOD AS INDICATED BY THE ECMWF AND THE GFS. THIS SMALL BEND TO THE WEST-NORTHWEST IS REFLECTED IN THE OFFICIAL FORECAST."

Man, those small bends are the killers.

The posts in this forum are NOT official forecast and should not be used as such. They are just the opinion of the poster and may or may not be backed by sound meteorological data. They are NOT endorsed by any professional institution or storm2k.org. For official information, please refer to the NHC and NWS products.

[WeatherGuesser]

Actually, if you look at the 5PM, the bend was there also, albeit less pronounced.

I keep saying that people are too fast to jump to conclusions based on historical tracks and that the last 2-3 years have not been following those tracks. People need to be more open minded and not get into the 'it has to do this' or 'it can't do that' mindset. We should have learned by now that nearly anything is possible except storms rotating clockwise.

[ozonepete]

Boy is the convection blowing up now.

[ozonepete]

Actually, if you look at the 5PM, the bend was there also, albeit less pronounced.

I keep saying that people are too fast to jump to conclusions based on historical tracks and that the last 2-3 years have not been following those tracks. People need to be more open minded and not get into the 'it has to do this' or 'it can't do that' mindset. We should have learned by now that nearly anything is possible except storms rotating clockwise.

Yeah. I'm not a big believer in past tracks, unless you can show me a detailed analysis of the atmosphere at all levels during every day of those prior storms' existence. Climatology is a "fair" indicator, but it's way more complicated than that.

[BigA]

[quote="ozonepete"]Boy is the convection blowing up now.

quote]

Center well-tucked under the convection right now...typical nighttime blowup of sheared systems. But the shear over Katia doesn't look to be fatal, and the ULL looks to be just starting to beat a retreat northbound. This plus non of the reliable models forecasting significant weakening tells me that Katia should survive.

[meriland23]

Looks like NHC agrees with that curve


http://www.nhc.noaa.gov/refresh/graphic ... e#contents

[Steve H.]

UKMET isn't all that reliable. I would take the Euro over it any day.

[meriland23]

(bold areas are pieces that might interest you)
[quoting from NHC]

000
WTNT42 KNHC 020237
TCDAT2

TROPICAL STORM KATIA DISCUSSION NUMBER 16
NWS NATIONAL HURRICANE CENTER MIAMI FL AL122011
1100 PM AST THU SEP 01 2011

MICROWAVE IMAGES AROUND 2245 UTC SHOWED THE CENTER OF KATIA ON THE
EDGE OF THE DEEP CONVECTION...BUT MORE RECENT SATELLITE IMAGES SHOW
AN INCREASE OF THE THUNDERSTORM ACTIVITY AND IT APPEARS THAT THE
CENTER IS AGAIN UNDER THE CANOPY. THE OUTFLOW HAS ALSO BECOME A
LITTLE BETTER DEFINED IN THE NORTHWEST QUADRANT.
DVORAK T-NUMBERS
ONLY SUPPORT 55 KNOTS BUT GIVEN THAT THE CLOUD PATTERN IS A LITTLE
BETTER ORGANIZED THAN EARLIER THIS EVENING...THE INITIAL INTENSITY
IS KEPT AT 60 KNOTS. WATER VAPOR IMAGES STILL SHOW A SHARP
UPPER-TROUGH WITH ITS AXIS ALONG 56 DEGREES WEST LONGITUDE INDUCING
STRONG SOUTHWESTERLY SHEAR OVER KATIA. GLOBAL MODELS...MAINLY THE
GFS AND EVENTUALLY THE ECMWF INSIST ON WEAKENING THIS TROUGH AND
FORECAST A MORE FAVORABLE ENVIRONMENT FOR INTENSIFICATION IN A DAY
OR SO. THERE ARE NO SIGNS THAT THE TROUGH IS WEAKENING YET...AND
GIVEN THE CURRENT SHEAR...NO CHANGE IN STRENGTH IS INDICATED IN THE
NEXT 12 TO 18 HOURS. KATIA SHOULD BEGIN TO RE-INTENSIFY IN ABOUT 24
TO 36 HOURS AND BECOME A MAJOR HURRICANE IN A FEW DAYS ASSUMING
THAT THE ENVIRONMENT BECOMES LESS HOSTILE AS INDICATED BY GLOBAL
MODELS.

KATIA HAS SLOWED DOWN A LITTLE BIT AND IT APPEARS TO BE MOVING
TOWARD THE WEST-NORTHWEST OR 290 DEGREES AT 14 KNOTS AROUND THE
PERIPHERY OF THE SUBTROPICAL RIDGE. A TROUGH CURRENTLY LOCATED OVER
THE WESTERN ATLANTIC IS ERODING THE WESTERN SIDE OF THE SUBTROPICAL
RIDGE AND THIS WILL INDUCE A NORTHWESTERLY MOTION DURING THE NEXT
TWO TO THREE DAYS. HOWEVER...IN THE LONG RANGE...A STRONG MID-LEVEL
TROUGH IS FORECAST TO DEVELOP OVER THE GULF OF MEXICO AS THE
ATLANTIC SUBTROPICAL RIDGE BUILDS WESTWARD. THIS PATTERN SHOULD
FORCE KATIA ON A MORE WEST-NORTHWESTWARD MOTION BY THE END OF THE
FORECAST PERIOD AS INDICATED BY THE ECMWF AND THE GFS. THIS SMALL
BEND TO THE WEST-NORTHWEST IS REFLECTED IN THE OFFICIAL FORECAST.

ON THE FORECAST TRACK...KATIA WILL CONTINUE TO MOVE OVER OPEN WATER
DURING THE NEXT FIVE DAYS.


FORECAST POSITIONS AND MAX WINDS

INIT 02/0300Z 16.7N 50.6W 60 KT 70 MPH
12H 02/1200Z 17.5N 52.5W 60 KT 70 MPH
24H 03/0000Z 18.5N 54.0W 65 KT 75 MPH
36H 03/1200Z 19.5N 55.5W 75 KT 85 MPH
48H 04/0000Z 20.5N 57.0W 85 KT 100 MPH
72H 05/0000Z 22.5N 60.0W 95 KT 110 MPH
96H 06/0000Z 25.0N 63.5W 100 KT 115 MPH
120H 07/0000Z 26.5N 67.0W 105 KT 120 MPH

[terrapintransit]

That is a very ominous looking cone atm...It sure isn't screaming recurve by any means. Katia seems to be developing feelings for future Lee. That would not be a good marriage..

[meriland23]

That is a very ominous looking cone atm...It sure isn't screaming recurve by any means. Katia seems to be developing feelings for future Lee. That would not be a good marriage..

http://www.storm2k.org/weather//images/ ... 40_480.jpg

LOl, reminds me of myself that *special 7* days a month.. Lee, would be my fiancee huddled together in a little ball, sitting in a corner. I would be Katia, pointing the finger and racing towards him to yell at him about something even though I am not etirely sure of what he did wrong.. LOL