ATL: CHRIS - Post-Tropical

[CrazyC83]

AL, 03, 2012062200, , BEST, 0, 432N, 428W, 55, 987

[cycloneye]

TROPICAL STORM CHRIS DISCUSSION NUMBER 10
NWS NATIONAL HURRICANE CENTER MIAMI FL AL032012
1100 PM AST THU JUN 21 2012

TROPICAL STORM CHRIS RETAINS A TIGHT CIRCULATION THIS EVENING AS
BEST OBSERVED BY A 2349Z METOP-A MICROWAVE SATELLITE IMAGE FROM THE
NRL WEBSITE. AS THE CONVECTION IN THE INNER CORE HAS WARMED...THE
DVORAK TECHNIQUE CANNOT PROVIDE A DATA-T NUMBER FOR INTENSITY
ESTIMATES. THE MODEL EXPECTED T-NUMBER FROM SAB AND TAFB PROVIDE A
RANGE BETWEEN 45 AND 65 KT. A 2221Z AMSU PASS SUGGESTED AN
INTENSITY AROUND 55 KT FROM THE CIMSS TECHNIQUE. THE CURRENT
INTENSITY IS ASSESSED AT 55 KT...THOUGH WITH SUBSTANTIAL
UNCERTAINTY. THE CYCLONE SHOULD GRADUALLY SPIN DOWN WHILE OVER
QUITE CHILLY WATERS AND IT IS LIKELY THAT IT WILL BECOME A
POST-TROPICAL CYCLONE IN ABOUT 12 HOURS...OR SOONER...IF RELATIVELY
DEEP CONVECTION DOES NOT REDEVELOP OVER THE SYSTEM.

CHRIS IS MOVING NORTHWARD AT ABOUT 12 KT. THE TROPICAL STORM SHOULD
TURN TOWARD THE SOUTHWEST WITHIN A DAY AS IT IS ADVECTED AROUND
THE PERIPHERY OF A LARGE DEEP-LAYER CYCLONE. A SECONDARY SURFACE
LOW CURRENTLY SOUTHWEST OF CHRIS IS PROJECTED BY ALL OF THE
DYNAMICAL MODELS...EXCEPT FOR HWRF...TO ABSORB THE CIRCULATION OF
CHRIS IN ABOUT 24-36 HOURS. THE FORECAST TRACK IS NEAR THE
CONSENSUS OF THE DYNAMICAL MODELS AND SLIGHTLY TO THE WEST OF THE
PREVIOUS ADVISORY.

FORECAST POSITIONS AND MAX WINDS

INIT 22/0300Z 43.6N 42.9W 55 KT 65 MPH
12H 22/1200Z 44.2N 44.0W 50 KT 60 MPH...POST-TROPICAL
24H 23/0000Z 43.0N 45.5W 40 KT 45 MPH...POST-TROP/EXTRATROP
36H 23/1200Z...DISSIPATED

$$
FORECASTER LANDSEA

[CrazyC83]

It looks extratropical to me?

[brunota2003]

This ought to be interesting to watch...considering after the loop, if Chris survives, he'll be heading back toward the areas where he was just a hurricane at. Already appears to be moving NW in most recent satellite images.

Go Chris!

[Zanthe]

It looks extratropical to me?

Maybe...maybe JUST enough convection in the storm to keep it tropical. If this trend keeps up, extratropical for the next advisory, in my opinion, of course.

[cycloneye]

TROPICAL STORM CHRIS DISCUSSION NUMBER 11
NWS NATIONAL HURRICANE CENTER MIAMI FL AL032012
500 AM AST FRI JUN 22 2012

CHRIS CONTINUES TO WEAKEN AND IS TRANSITIONING TO A POST-TROPICAL
CYCLONE OVER THE NORTH ATLANTIC. SATELLITE IMAGES INDICATE THAT THE
STORM IS NOW DEVOID OF DEEP CONVECTION AND ONLY CONSISTS OF A TIGHT
SWIRL OF LOW- TO MID-LEVEL CLOUDS. THE INITIAL INTENSITY IS LOWERED
TO 45 KT...FOLLOWING THE DOWNWARD TREND IN THE DVORAK
CLASSIFICATIONS. CHRIS IS FORECAST TO WEAKEN FURTHER AND WILL
LIKELY COMPLETE ITS TRANSITION TO A POST-TROPICAL CYCLONE LATER
THIS MORNING.

THE CYCLONE HAS TURNED TO THE NORTHWEST AND THE LATEST INITIAL
MOTION ESTIMATE IS 315/12. CHRIS...OR ITS POST-TROPICAL
REMNANT...IS EXPECTED TO ROTATE COUNTER-CLOCKWISE AROUND A LARGER
EXTRATROPICAL LOW CURRENTLY LOCATED A FEW HUNDRED N MI TO ITS
SOUTH. THIS LARGER LOW WILL ULTIMATELY ABSORB WHATEVER IS LEFT OF
CHRIS IN 24 TO 36 HOURS. THE OFFICIAL FORECAST FOLLOWS THE
GUIDANCE PROVIDED BY THE OCEAN PREDICTION CENTER.

THE 34-KT WIND RADII HAVE BEEN MODIFIED BASED ON AN OSCAT PASS
AROUND 0200 UTC.

FORECAST POSITIONS AND MAX WINDS

INIT 22/0900Z 44.8N 44.5W 45 KT 50 MPH
12H 22/1800Z 44.3N 45.7W 40 KT 45 MPH...POST-TROPICAL
24H 23/0600Z 43.2N 45.5W 35 KT 40 MPH...POST-TROP/EXTRATROP
36H 23/1800Z...DISSIPATED

$$
FORECASTER CANGIALOSI

[brunota2003]

Chris got one last BT:

AL, 03, 2012062212, , BEST, 0, 448N, 455W, 45, 989, TS

But he is completely devoid of convection has he moves over SSTs (per the SSTs shown on the floater loops) in the 13C and below range. It was nice watching you, Chris

[Ptarmigan]

Gotta love it, most expected a very uneventful el nino hurricane season. (2) May TS w/ one landfall from the east into Jacksonville (crazy!!) and N Atlantic hurricane in June! Wow, I'm glad I bet the over w/ storm #'s prediction!

It shows that predicting hurricane season is not that easy and have a long way to go. The 2005 forecast was really underestimated. On the other hand, 2006 forecast was overestimated.

[Macrocane]

Bye Chris, you were an interesting and surprising system to watch.

[cycloneye]

Amazing it was indeed. Chris added good ACE numbers to the Atlantic.

Code: Select all

03L (Chris)
 
Operational
 
2.7200

North Atlantic Total

4.96