ATL: KATIA - Post Tropical - Discussion

[brunota2003]

Looks like it's been heading more WNW for the past couple hours to me. Even the 30 image loop on GHCC looked like at first it was NW, then it started heading closer to WNW.

I wish we could get a couple of G-IV flights out there...I'd put money down that the ridge is stronger than the models are thinking, it usually always is. Is it strong enough to bring Katia westward and hit the East Coast? I don't think so, but possibly enough to scare some unsuspecting people.

Note: 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.

[ozonepete]

Looks like it's been heading more WNW for the past couple hours to me. Even the 30 image loop on GHCC looked like at first it was NW, then it started heading closer to WNW.

I wish we could get a couple of G-IV flights out there...I'd put money down that the ridge is stronger than the models are thinking, it usually always is. Is it strong enough to bring Katia westward and hit the East Coast? I don't think so, but possibly enough to scare some unsuspecting people.

Note: 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.

Yup. Look at the satellite image of the Atlantic that I posted just above. The northern half is getting pulled northward by the bottom of what's left of that trough and the southern half can be seen getting pushed westward as the ridge builds behind and a little NE of it. The net result is still NW, but at times the westward push of the building ridge is winning out. This kind of tug in two directions is one of the reasons we see the eye wobble (just one - there are definitely others.) I would have to say that given all of these factors, it will stay on a net NW track tonight.

[SouthernBreeze]

Yesterday they said they were considering a G-IV research flight Tue - anyone know if that's still on?

[cycloneye]

BULLETIN
HURRICANE KATIA ADVISORY NUMBER 32
NWS NATIONAL HURRICANE CENTER MIAMI FL AL122011
1100 PM AST MON SEP 05 2011

...KATIA BECOMES A CATEGORY FOUR HURRICANE...DANGEROUS RIP CURRENTS
ARE THE MAIN HAZARD ALONG U.S. EAST COAST AND BERMUDA...


SUMMARY OF 1100 PM AST...0300 UTC...INFORMATION
-----------------------------------------------
LOCATION...25.8N 64.4W
ABOUT 450 MI...725 KM S OF BERMUDA
MAXIMUM SUSTAINED WINDS...135 MPH...215 KM/H
PRESENT MOVEMENT...NW OR 315 DEGREES AT 10 MPH...17 KM/H
MINIMUM CENTRAL PRESSURE...946 MB...27.94 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 HURRICANE KATIA WAS
LOCATED NEAR LATITUDE 25.8 NORTH...LONGITUDE 64.4 WEST. KATIA IS
MOVING TOWARD THE NORTHWEST NEAR 10 MPH...17 KM/H...AND THIS GENERAL
MOTION IS EXPECTED TO CONTINUE THROUGH WEDNESDAY

MAXIMUM SUSTAINED WINDS HAVE INCREASED TO NEAR 135 MPH...215 KM/H...
WITH HIGHER GUSTS. KATIA IS A CATEGORY FOUR HURRICANE ON THE
SAFFIR-SIMPSON HURRICANE WIND SCALE. SOME FLUCTUATIONS IN STRENGTH
ARE POSSIBLE DURING THE NEXT 24 HOURS...FOLLOWED BY SLOW WEAKENING.

HURRICANE FORCE WINDS EXTEND OUTWARD UP TO 60 MILES...95 KM...FROM
THE CENTER...AND TROPICAL STORM FORCE WINDS EXTEND OUTWARD UP TO 205
MILES...335 KM.

ESTIMATED MINIMUM CENTRAL PRESSURE IS 946 MB...27.94 INCHES.


HAZARDS AFFECTING LAND
----------------------
SURF...LARGE SWELLS GENERATED BY KATIA ARE EXPECTED TO AFFECT MOST
OF THE EAST COAST OF THE UNITED STATES...BERMUDA...THE GREATER
ANTILLES...AND EAST-FACING BEACHES OF THE BAHAMAS DURING THE NEXT
FEW DAYS. THESE SWELLS ARE LIKELY TO CAUSE LIFE-THREATENING SURF
AND RIP CURRENT CONDITIONS. SWELLS AFFECTING THE NORTHERN LEEWARD
ISLANDS SHOULD CONTINUE TO SUBSIDE OVERNIGHT. PLEASE CONSULT
PRODUCTS FROM YOUR LOCAL WEATHER SERVICE OFFICE FOR ADDITIONAL
INFORMATION.


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

$$
FORECASTER CANGIALOSI



HURRICANE KATIA DISCUSSION NUMBER 32
NWS NATIONAL HURRICANE CENTER MIAMI FL AL122011
1100 PM AST MON SEP 05 2011

SATELLITE IMAGES INDICATE THAT KATIA HAS STRENGTHENED CONSIDERABLY
DURING THE PAST SEVERAL HOURS. AS THE ASSOCIATED DEEP CONVECTION
BECAME MUCH MORE SYMMETRIC AND THE EYE WARMED DURING THE EVENING
HOURS...DVORAK CLASSIFICATIONS FROM TAFB AND SAB INCREASED TO
6.0/115 KT AT 0000 UTC. DESPITE SOME FLUCTUATIONS IN THE APPEARANCE
OF THE EYE OVER THE LAST HOUR OR TWO...ADT ESTIMATES FROM UW-CIMSS
ARE STILL 6.2/122 KT...SO THE INITIAL INTENSITY IS INCREASED TO 115
KT...MAKING KATIA A CATEGORY FOUR HURRICANE.

THE LATEST 12-HOUR INITIAL MOTION ESTIMATE IS 315/9...A TOUCH SLOWER
THAN NOTED IN THE PREVIOUS PACKAGE. THE TRACK FORECAST REASONING IS
UNCHANGED. KATIA IS EXPECTED TO CONTINUE MOVING NORTHWESTWARD FOR
THE NEXT 36 HOURS AS IT REMAINS ON THE SOUTHWESTERN PERIPHERY OF
THE SUBTROPICAL RIDGE. A TURN TOWARD THE NORTH IS FORECAST IN 48 TO
72 HOURS AS THE HURRICANE BECOMES EMBEDDED IN SOUTHERLY FLOW
BETWEEN THE RIDGE AND A LARGE CUTOFF LOW OVER THE EASTERN UNITED
STATES. THIS STEERING PATTERN WILL ALLOW KATIA TO MOVE BETWEEN
BERMUDA AND THE UNITED STATES EAST COAST DURING THAT TIME PERIOD.
AFTER THAT...A SHARP NORTHEASTWARD AND EAST-NORTHEASTWARD TURN WITH
AN INCREASE IN FORWARD SPEED IS FORECAST AS KATIA GETS CAUGHT IN
THE MID-LATITUDE WESTERLIES. THE MODEL SOLUTIONS HAVE BEEN
CONVERGING DURING THE PAST FEW CYCLES AND ARE NOW IN RELATIVELY
GOOD AGREEMENT...INCREASING CONFIDENCE IN THE TRACK FORECAST. THE
OFFICIAL FORECAST IS SIMILAR TO THE PREVIOUS ONE AND NEAR THE
MIDDLE OF THE GUIDANCE ENVELOPE.

FLUCTUATIONS IN THE INTENSITY OF KATIA ARE LIKELY DURING THE NEXT 12
TO 24 HOURS...PERHAPS DUE TO EYEWALL REPLACEMENT CYCLES...AS THE
MAJOR HURRICANE REMAINS IN A FAVORABLE ENVIRONMENT. SLOW WEAKENING
IS EXPECTED BEYOND THAT TIME AS KATIA MOVES INTO AN ENVIRONMENT OF
MODERATE SHEAR AND SLIGHTLY COOLER WATERS. THE NEW NHC INTENSITY
FORECAST HAS BEEN ADJUSTED UPWARD THROUGH 36 HOURS BASED ON THE
OBSERVED STRENGTHENING AND IS NEAR THE MODEL CONSENSUS. KATIA IS
NOW FORECAST TO BE A POST-TROPICAL CYCLONE BY DAY 5...AS IT IS
EXPECTED TO BE WELL-EMBEDDED IN THE WESTERLIES AND OVER 20-21C
WATERS BY THAT TIME.

DRIFTING BUOY 41855...WHICH WAS LOCATED ABOUT 20 N MI NORTHEAST OF
THE EYE OF KATIA AT 0000 UTC...REPORTED A MINIMUM PRESSURE OF 952
MB.

FORECAST POSITIONS AND MAX WINDS

INIT 06/0300Z 25.8N 64.4W 115 KT 135 MPH
12H 06/1200Z 26.9N 65.5W 115 KT 135 MPH
24H 07/0000Z 28.1N 66.9W 115 KT 135 MPH
36H 07/1200Z 29.4N 68.3W 110 KT 125 MPH
48H 08/0000Z 30.9N 69.5W 100 KT 115 MPH
72H 09/0000Z 35.4N 69.7W 90 KT 105 MPH
96H 10/0000Z 39.5N 63.5W 75 KT 85 MPH
120H 11/0000Z 42.5N 48.0W 65 KT 75 MPH

$$
FORECASTER CANGIALOSI

[cycloneye]

At 11 PM is a Cat 4

...KATIA BECOMES A CATEGORY FOUR HURRICANE...DANGEROUS RIP CURRENTS
ARE THE MAIN HAZARD ALONG U.S. EAST COAST AND BERMUDA...


SUMMARY OF 1100 PM AST...0300 UTC...INFORMATION
-----------------------------------------------
LOCATION...25.8N 64.4W
ABOUT 450 MI...725 KM S OF BERMUDA
MAXIMUM SUSTAINED WINDS...135 MPH...215 KM/H
PRESENT MOVEMENT...NW OR 315 DEGREES AT 10 MPH...17 KM/H
MINIMUM CENTRAL PRESSURE...946 MB...27.94 INCHES

[GCANE]

Looks like an EWRC could be starting up.

Just in the last few frames:

Strong inner eyewall on the NE Quad and new secondary eyewall forming on the SW quad.

New eyewall looks pretty strong and forming fast.

Looking at Funktop, the green flashes indicates she still is firing small rapid hot towers on the inner eyewall.

She is tracking into the anti-cyclone, so if the EWRC goes quick, she could still ramp up.


http://tropic.ssec.wisc.edu/real-time/m ... splay.html

http://www.ssd.noaa.gov/goes/flt/t2/flash-ft.html

[Patrick99]

That storm is a Cat 4? Katia might be the worst-looking Cat 4 on satellite presentation I've ever seen. She's not winning any hurricane beauty contests, that's for sure.

[supercane]

Latest microwave from about 3 hours ago:

[ozonepete]

That storm is a Cat 4? Katia might be the worst-looking Cat 4 on satellite presentation I've ever seen. She's not winning any hurricane beauty contests, that's for sure.

LOL. It had a pretty good symmetry just a few hours ago, which is when the NHC analysed it. But as I said before, it's now undergoing a push from behind by the building ridge and a tug to the north by the passing trough. By getting tugs and pushes in two different directions the symmetry is collapsing fast - it's trying to go north and west at the same time. IMHO. this is not good at all for any more strengthening in the near term. In fact the last few satellite images tell me this will weaken a lot over the short term. This point, where a hurricane is entering a serious recurve, is often where they lose a lot of power because they lose symmetry. That really nice ramp-up may be the last for Katia.

Maybe it could ramp up one more time after it corrects to a northerly track and this weakening ends, but it's running out of time before the Oceanic Heat Content drops off.

[Macrocane]

I recommend to some members to watch loops and not only single images, as ozonepete mentioned Katia looked better a few hours ago and that's why they upgraded it, IMO D-max should help Katia to regain organization in a few hours.

[wx4me]

Does anyone know where I can find an "extended" loop of Katia? IE: like an animated IR image of the last few days or more of Katia?? I know I have seen extended loops of past storms before?

[Macrocane]

Maybe this could help you http://rammb.cira.colostate.edu/products/tc_realtime/archive.asp?product=4kmirimg&storm_identifier=AL122011

[wx4me]

:uarrow: Maybe this could help you http://rammb.cira.colostate.edu/products/tc_realtime/archive.asp?product=4kmirimg&storm_identifier=AL122011

YEP!! Thank You VERY MUCH Macrocane!!

[ozonepete]

I recommend to some members to watch loops and not only single images, as ozonepete mentioned Katia looked better a few hours ago and that's why they upgraded it, IMO D-max should help Katia to regain organization in a few hours.

Yeah, you are probably right here, macro, as you usually are. It's a very strong hurricane now and sure looks like it's fighting to establish good symmetry again. There still aren't any negatives outside of the lack of symmetry, and in these cases a category 4 will often win out and maintain itself.

[cheezyWXguy]

I recommend to some members to watch loops and not only single images, as ozonepete mentioned Katia looked better a few hours ago and that's why they upgraded it, IMO D-max should help Katia to regain organization in a few hours.

Yeah, you are probably right here, macro, as you usually are. It's a very strong hurricane now and sure looks like it's fighting to establish good symmetry again. There still aren't any negatives outside of the lack of symmetry, and in these cases a category 4 will often win out and maintain itself.

yeah theres a pretty intense ring of red around the eye now, although that eye does look a tad ragged. still looks like a 4 to me.

[Ptarmigan]

Katia has come a long way.

[Macrocane]

Yeah, you are probably right here, macro, as you usually are. It's a very strong hurricane now and sure looks like it's fighting to establish good symmetry again. There still aren't any negatives outside of the lack of symmetry, and in these cases a category 4 will often win out and maintain itself.

Thanks ozone, although I think you're right more often than I am I agree with you and cheezyWXguy it looks like it's trying to strengthen again, still looks kind of ragged and lopsided but looks a little better than it did by the time of the advisory.

[toto]

.

How far was the earthquake from the hurricane's path ?

http://earthquake.usgs.gov/earthquakes/ ... merica.php

http://earthquake.usgs.gov/earthquakes/ ... 005pl2.php


.

[WeatherGuesser]

Hurricane Katia weakens to a Category 3 storm

(AP) – 18 minutes ago

MIAMI (AP) — Hurricane Katia has weakened to a Category 3 storm as it moves across the Atlantic Ocean after briefly becoming a Category 4 system.

The U.S. National Hurricane Center in Miami says Katia's maximum sustained winds early Tuesday have decreased to near 125 mph (205 kph). The hurricane center says some fluctuation in strength is possible over the next 24 hours followed by slow weakening.

Forecast maps show Katia veering to the northeast, away from the U.S. in the coming week, but the hurricane center says large swells from the hurricane could affect the East Coast, Bermuda, the Greater Antilles and parts of the Bahamas over the next few days.

Katia is centered about 400 miles (645 kilometers) south of Bermuda and moving northwest near 10 mph (17 kph).

http://www.google.com/hostednews/ap/art ... f154cfbb28

[WeatherGuesser]

AT 500 AM AST...0900 UTC...THE CENTER OF HURRICANE KATIA WAS LOCATED
NEAR LATITUDE 26.5 NORTH...LONGITUDE 65.1 WEST. KATIA IS MOVING
TOWARD THE NORTHWEST NEAR 10 MPH...17 KM/H. THIS GENERAL MOTION
IS EXPECTED TO CONTINUE THROUGH WEDNESDAY...FOLLOWED BY A TURN
TOWARD THE NORTH-NORTHWEST BY THURSDAY.

MAXIMUM SUSTAINED WINDS HAVE DECREASED TO NEAR 125 MPH...205
KM/H...WITH HIGHER GUSTS. KATIA IS A CATEGORY THREE HURRICANE ON
THE SAFFIR-SIMPSON WIND SCALE. SOME FLUCTUATIONS IN STRENGTH ARE
POSSIBLE DURING THE NEXT 24 HOURS...FOLLOWED BY SLOW WEAKENING.