EPAC : TROPICAL DEPRESSION CARLOS (04E)

[Aric Dunn]

highly doubtful with that system near, the inflow is severely limited on the east side..

I could be wrong, but I don't think it is close enough to cause a hurricane to barf outflow boundaries and get downgraded to a tropical storm.


Should be an official invest soon, if I had to guess...

that image does no justice.. the sat loop tell a much better story .. you can clearly see the split flow in the low levels. the large circualtion is clearly affecting the inflow on the east side and Se. if you take a look here http://www.ssd.noaa.gov/goes/flt/t7/loop-rgb.html

and pay attention to the flow going to the system to the east.

here is a image with a outline for you . ( sorry for the crudeness)
but without the strong inflow that you typically would see in that quadrant, we are not going to see a strengthing system and i highly sugest looking at the loop

[Iceman56]

Don't get me wrong. Overall the thesis looks good and there's some great stuff in there. My point is that you cannot take a hypothesis from a thesis (that lack of wind shear prevents dry air intrusion, which he states in his summary is, indeed, only a hypothesis), and claim it as an absolute, as he did here.

Thus, "dry air cannot get into a storm if there is no shear" does not equal "it was hypothesized that strong shear allows the dry air to penetrate into the inner core region of the TC."

Suffice to say that I'm a professional met, have been for a long time (longer than I'd like to admit), and although I won't claim to be one of the TC "gods" by any stretch, I'm quite well qualified to discuss tropical cyclones.

[Aric Dunn]

Don't get me wrong. Overall the thesis looks good and there's some great stuff in there. My point is that you cannot take a hypothesis from a thesis (that lack of wind shear prevents dry air intrusion, which he states in his summary is, indeed, only a hypothesis), and claim it as an absolute, as he did here.

Suffice to say that I'm a professional met, have been for a long time (longer than I'd like to admit), and although I won't claim to be one of the TC "gods" by any stretch, I'm quite well qualified to discuss tropical cyclones.

lol .. no comment... but whos that from ?

[Derek Ortt]

perhaps I overstated the hypothesis from my M.S. thesis here

I should have said, it is unlikely that dry air reaches the core without shear or some other convective disruption. Yes, we had dry air today as evidenced by the outflow boundaries. Was there some other disruption... that I am not sure but I suspect there was

[cycloneye]

WTPZ34 KNHC 130243
TCPEP4
BULLETIN
TROPICAL STORM CARLOS ADVISORY NUMBER 12
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL EP042009
800 PM PDT SUN JUL 12 2009

AT 800 PM PDT...0300 UTC...THE CENTER OF TROPICAL STORM CARLOS WAS
LOCATED NEAR LATITUDE 10.2 NORTH...LONGITUDE 123.0 WEST OR ABOUT
1230 MILES...1985 KM...SOUTHWEST OF THE SOUTHERN TIP OF BAJA
CALIFORNIA.

CARLOS IS MOVING TOWARD THE WEST NEAR 12 MPH...19 KM/HR...AND THIS
GENERAL MOTION IS EXPECTED TO CONTINUE DURING THE NEXT COUPLE OF
DAYS.

MAXIMUM SUSTAINED WINDS ARE NEAR 60 MPH...95 KM/HR...WITH HIGHER
GUSTS. SOME STRENGTHENING IS FORECAST DURING THE NEXT DAY OR TWO.

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

ESTIMATED MINIMUM CENTRAL PRESSURE IS 994 MB...29.35 INCHES.

...SUMMARY OF 800 PM PDT INFORMATION...
LOCATION...10.2N 123.0W
MAXIMUM SUSTAINED WINDS...60 MPH
PRESENT MOVEMENT...WEST OR 270 DEGREES AT 12 MPH
MINIMUM CENTRAL PRESSURE...994 MB

THE NEXT ADVISORY WILL BE ISSUED BY THE NATIONAL HURRICANE CENTER AT
200 AM PDT.

$$
FORECASTER BROWN



WTPZ24 KNHC 130242
TCMEP4
TROPICAL STORM CARLOS FORECAST/ADVISORY NUMBER 12
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL EP042009
0300 UTC MON JUL 13 2009

TROPICAL STORM CENTER LOCATED NEAR 10.2N 123.0W AT 13/0300Z
POSITION ACCURATE WITHIN 25 NM

PRESENT MOVEMENT TOWARD THE WEST OR 270 DEGREES AT 10 KT

ESTIMATED MINIMUM CENTRAL PRESSURE 994 MB
MAX SUSTAINED WINDS 50 KT WITH GUSTS TO 60 KT.
50 KT....... 20NE 20SE 0SW 0NW.
34 KT....... 50NE 50SE 30SW 50NW.
12 FT SEAS..150NE 90SE 45SW 90NW.
WINDS AND SEAS VARY GREATLY IN EACH QUADRANT. RADII IN NAUTICAL
MILES ARE THE LARGEST RADII EXPECTED ANYWHERE IN THAT QUADRANT.

REPEAT...CENTER LOCATED NEAR 10.2N 123.0W AT 13/0300Z
AT 13/0000Z CENTER WAS LOCATED NEAR 10.2N 122.3W

FORECAST VALID 13/1200Z 10.2N 124.6W
MAX WIND 55 KT...GUSTS 65 KT.
50 KT... 20NE 20SE 0SW 0NW.
34 KT... 50NE 50SE 30SW 50NW.

FORECAST VALID 14/0000Z 10.4N 126.9W
MAX WIND 60 KT...GUSTS 75 KT.
50 KT... 25NE 25SE 0SW 20NW.
34 KT... 60NE 60SE 45SW 60NW.

FORECAST VALID 14/1200Z 10.6N 129.1W
MAX WIND 65 KT...GUSTS 80 KT.
64 KT... 15NE 15SE 0SW 15NW.
50 KT... 30NE 30SE 20SW 30NW.
34 KT... 75NE 75SE 50SW 75NW.

FORECAST VALID 15/0000Z 10.9N 131.2W
MAX WIND 65 KT...GUSTS 80 KT.
50 KT... 30NE 30SE 20SW 30NW.
34 KT... 75NE 75SE 50SW 75NW.

FORECAST VALID 16/0000Z 11.7N 135.3W
MAX WIND 60 KT...GUSTS 75 KT.
50 KT... 30NE 30SE 20SW 30NW.
34 KT... 75NE 75SE 50SW 75NW.

EXTENDED OUTLOOK. NOTE...ERRORS FOR TRACK HAVE AVERAGED NEAR 200 NM
ON DAY 4 AND 225 NM ON DAY 5...AND FOR INTENSITY NEAR 20 KT EACH DAY

OUTLOOK VALID 17/0000Z 12.5N 140.0W
MAX WIND 55 KT...GUSTS 65 KT.

OUTLOOK VALID 18/0000Z 12.5N 145.0W
MAX WIND 45 KT...GUSTS 55 KT.

REQUEST FOR 3 HOURLY SHIP REPORTS WITHIN 300 MILES OF 10.2N 123.0W

NEXT ADVISORY AT 13/0900Z

$$
FORECASTER BROWN

075
WTPZ44 KNHC 130244
TCDEP4
TROPICAL STORM CARLOS DISCUSSION NUMBER 12
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL EP042009
800 PM PDT SUN JUL 12 2009

THE MYSTERIOUS WEAKENING TREND THAT BEGAN EARLY THIS MORNING HAS
CONTINUED THROUGHOUT THE DAY. SATELLITE IMAGES SHOW THAT THE
CONVECTIVE BANDING HAS BECOME LESS DEFINED AND ONLY A SMALL AREA
OF CONVECTION REMAINS NEAR THE CENTER OF CARLOS. OBJECTIVE AND
SUBJECTIVE DVORAK DATA T-NUMBERS HAVE CONTINUED TO DECREASE AND
SUPPORT A SOMEWHAT UNCERTAIN INITIAL INTENSITY OF 50 KT. DESPITE
THE RAGGED APPEARANCE IN SATELLITE IMAGERY A VERY RECENT 0150 UTC
SSMIS MICROWAVE IMAGE SHOWS WHAT APPEARS TO BE AN EYE-LIKE FEATURE.
PERHAPS THIS IS AN INDICATION THAT CARLOS IS TRYING TO RE-ORGANIZE.

DESPITE THE WEAKENING THAT HAS OCCURRED DURING THE PAST 24 HOURS...
THE FORECAST PATH KEEPS CARLOS OVER 28 DEGREE CELSIUS WATER AND IN
A LOW SHEAR ENVIRONMENT DURING THE NEXT 2 TO 3 DAYS. HOWEVER...THE
GFDL AND GFDN MODELS ARE THE ONLY GUIDANCE THAT PREDICTS
SIGNIFICANT RESTRENGTHENING. THE HWRF HAS BACKED-OFF ON ITS
EARLIER FORECAST OF RE-INTENSIFICATION AND NOW CALLS FOR GRADUAL
WEAKENING TO BELOW TROPICAL STORM STRENGTH IN A COUPLE OF DAYS.
THE SHIPS/LGEM GUIDANCE MAINTAIN CARLOS AS A 45 TO 55 KT TROPICAL
STORM THROUGHOUT THE 5 DAY PERIOD. SINCE THE OVERALL CONDITIONS
APPEAR FAVORABLE FOR INTENSIFICATION THE OFFICIAL FORECAST WILL
CONTINUE TO CALL FOR SOME MODEST RESTRENGTHENING...BUT A LITTLE
LESS THAN THE PREVIOUS ADVISORY. AFTER 72 HOURS...SHEAR IS EXPECTED
TO INCREASE AND GRADUAL WEAKENING IS SHOWN AT THAT TIME.

THE INITIAL MOTION ESTIMATE IS 265/10. THE NOGAPS AND GFDN MODELS
CONTINUE TO FORECAST A TRACK MORE TOWARD THE NORTH THAN THE REST OF
THE GUIDANCE. THE NEW OFFICIAL FORECAST FOLLOWS THE CONSENSUS OF
THE REMAINDER OF THE TRACK MODELS...WHICH ARE TIGHTLY CLUSTERED ON
A WEST TO WEST-NORTHWESTWARD PATH THAT IS CLOSE TO THE PREVIOUS
OFFICIAL FORECAST.

FORECAST POSITIONS AND MAX WINDS

INITIAL 13/0300Z 10.2N 123.0W 50 KT
12HR VT 13/1200Z 10.2N 124.6W 55 KT
24HR VT 14/0000Z 10.4N 126.9W 60 KT
36HR VT 14/1200Z 10.6N 129.1W 65 KT
48HR VT 15/0000Z 10.9N 131.2W 65 KT
72HR VT 16/0000Z 11.7N 135.3W 60 KT
96HR VT 17/0000Z 12.5N 140.0W 55 KT
120HR VT 18/0000Z 12.5N 145.0W 45 KT

$$
FORECASTER BROWN

[Derek Ortt]

this is not that disorganized

http://www.nrlmry.navy.mil/tc_pages/tc0 ... atest.html. Clear eye present even with this low resolution data

[tolakram]

Well, the SST's on that flash loop miht be wrong but Carlos is exiting the phantom cooler water and looks to be regenerating.

Yes, I really have no idea if the SST data is correct or not.

http://www.ssd.noaa.gov/goes/flt/t7/flash-avn.html

[Aric Dunn]

this is not that disorganized

http://www.nrlmry.navy.mil/tc_pages/tc0 ... atest.html. Clear eye present even with this low resolution data

its still lacking significant inflow in the eastern quad... there is almost no banding at all in the east quad in that image... but I agree it trying to hang on .. but very limited

[CrazyC83]

50 kt may be bringing it down too much with the well-defined eyewall. This is quite reminiscent of Marco and Polo last year, and Dvorak doesn't do very well with tiny circulations.

Smaller storms are also far more sensitive to intensity changes, so it could easily go back into rapid deepening - or dissipate. It could go either way.

[HURAKAN]

Not bad.

[MGC]

Appears convection is on the increase. Perhaps the dry air that Carlos injested has run its limit. Little shear and warm ocean temps ahead, I see no reason for Carlos not to intensify.....MGC

[Derek Ortt]

looks like mid level NE shear is still present. I'll check again in morning when I am not half asleep

[wxmann_91]

dry air cannot get into a storm if there is no shear

the stratocu deck is well to the north, that's not an issue.

I wish we had some obs... I'd love to see a sounding to check the lapse rate

My bad... stable air would have been more appropriate (and I certainly know the difference between dry and stable).


And yes, I agree, a sounding would help soooo much right now.

[Ptarmigan]

Carlos is weakening quite a bit.

[senorpepr]

WTPZ34 KNHC 130832
TCPEP4
BULLETIN
TROPICAL STORM CARLOS ADVISORY NUMBER 13
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL EP042009
200 AM PDT MON JUL 13 2009

...CARLOS A LITTLE WEAKER...

AT 200 AM PDT...0900 UTC...THE CENTER OF TROPICAL STORM CARLOS WAS
LOCATED NEAR LATITUDE 10.2 NORTH...LONGITUDE 124.1 WEST OR ABOUT
1285 MILES...2065 KM...SOUTHWEST OF THE SOUTHERN TIP OF BAJA
CALIFORNIA.

CARLOS IS MOVING TOWARD THE WEST NEAR 13 MPH...20 KM/HR...AND THIS
GENERAL MOTION IS EXPECTED TO CONTINUE OVER THE NEXT COUPLE OF DAYS.

MAXIMUM SUSTAINED WINDS HAVE DECREASED TO NEAR 50 MPH...85
KM/HR...WITH HIGHER GUSTS. SOME STRENGTHENING IS POSSIBLE DURING
THE NEXT DAY OR TWO.

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

ESTIMATED MINIMUM CENTRAL PRESSURE IS 1000 MB...29.53 INCHES.

...SUMMARY OF 200 AM PDT INFORMATION...
LOCATION...10.2N 124.1W
MAXIMUM SUSTAINED WINDS...50 MPH
PRESENT MOVEMENT...WEST OR 270 DEGREES AT 13 MPH
MINIMUM CENTRAL PRESSURE...1000 MB

THE NEXT ADVISORY WILL BE ISSUED BY THE NATIONAL HURRICANE CENTER AT
800 AM PDT.

$$
FORECASTER KIMBERLAIN/PASCH


WTPZ44 KNHC 130834
TCDEP4
TROPICAL STORM CARLOS DISCUSSION NUMBER 13
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL EP042009
200 AM PDT MON JUL 13 2009

CARLOS CONSISTS OF AN AMORPHOUS BLOB OF DEEP CONVECTION WITH A FEW
POORLY-DEFINED BANDING FEATURES OVER THE SOUTHERN AND WESTERN
PORTIONS OF THE CIRCULATION. ITS RECENT APPEARANCE REPRESENTS A
DECREASE IN ORGANIZATION...AND SUBJECTIVE DVORAK T-NUMBERS OF 2.5
AND 3.0 FROM SAB AND TAFB...RESPECTIVELY...REFLECT A GRADUAL
WEAKENING. THEREFORE THE INITIAL INTENSITY IS LOWERED TO 45
KT...WITHIN THE REALM OF AVAILABLE ESTIMATES.

THE WEAKENING OF CARLOS OBSERVED DURING THE PAST 24 HOURS HAS INDEED
BEEN PUZZLING...AND THUS THE INTENSITY FORECAST IS OF LOW
CONFIDENCE. CARLOS HAS WELL-DEFINED UPPER-LEVEL OUTFLOW...AND IS
IN AN ENVIRONMENT OF LOW VERTICAL WIND SHEAR AND RELATIVELY WARM
SEA SURFACE TEMPERATURES. ALL OF THESE FACTORS SHOULD FAVOR
INTENSIFICATION...YET THE CYCLONE HAS WEAKENED 30 KT SINCE THIS
TIME YESTERDAY. THIS IS ANOTHER EXAMPLE OF OUR LACK OF
UNDERSTANDING OF TROPICAL CYCLONE INTENSITY CHANGE. NO MATTER THE
INEXPLICABLE WEAKENING...THE GFDL AND GFDN MODELS PREDICT THAT
CARLOS WILL REACQUIRE HURRICANE STATUS...WHILE SHIPS INDICATES
LITTLE FURTHER DEVELOPMENT...AND THE HWRF WEAKENS CARLOS TO A
TROPICAL DEPRESSION. GIVEN RECENT TRENDS AND THE LESS BULLISH
NUMERICAL GUIDANCE...THE OFFICIAL FORECAST WILL CALL FOR ONLY
MODEST STRENGTHENING EVEN THOUGH ENVIRONMENTAL CONDITIONS ARE
EXPECTED TO REMAIN FAVORABLE FOR THE NEXT 2 TO 3 DAYS.
THEREAFTER...A SUBTLE INCREASE IN WESTERLY FLOW ALOFT AND SLIGHTLY
COOLER WATERS SHOULD RESULT IN WEAKENING.

THE INITIAL MOTION ESTIMATE IS 270/11. THE NOGAPS AND GFDN MODELS
REMAIN NORTHERN OUTLIERS...AND ARE DISCOUNTED AS MOST DYNAMICAL
GUIDANCE INDICATES THE MID-LEVEL SUBTROPICAL RIDGE REMAINING
WELL-ESTABLISHED TO THE NORTH OF CARLOS THROUGH THE FORECAST
PERIOD. ESSENTIALLY...THE NEW OFFICIAL FORECAST IS AN UPDATE OF
THE PREVIOUS ADVISORY BUT IS FARTHER SOUTH THAN THE MODEL
CONSENSUS...SINCE THE LATTER INCLUDES THE QUESTIONABLE NOGAPS AND
GFDN SOLUTIONS.

FORECAST POSITIONS AND MAX WINDS

INITIAL 13/0900Z 10.2N 124.1W 45 KT
12HR VT 13/1800Z 10.2N 125.8W 50 KT
24HR VT 14/0600Z 10.4N 128.0W 50 KT
36HR VT 14/1800Z 10.7N 130.2W 55 KT
48HR VT 15/0600Z 11.1N 132.3W 55 KT
72HR VT 16/0600Z 11.9N 136.4W 55 KT
96HR VT 17/0600Z 12.5N 141.0W 50 KT
120HR VT 18/0600Z 12.5N 145.5W 45 KT

$$
FORECASTER KIMBERLAIN/PASCH

[cyclonic chronic]

u can see the low level center here and there in between bouts of strong convection on vis. carlos ingested some dry air as it reached hurricane strength imo. i wish the l.i. index worked on the floater. then yesterday tried to push that air back out as seen in the outflow boundries. wow we are still in the infancy of intensity prediction, esp with tiny systems. guess thats what keeps us comin back for more.

[HURAKAN]

Puzzling Carlos

[Derek Ortt]

still has an eye on microwave

however, it has moved WSW

[Ed Mahmoud]

NHC has gone CODE RED on disturbance East of Carlos. Not remembering ftp page to look for upgrades, do we have a 96E yet?


Nevermind...

[Ed Mahmoud]

still has an eye on microwave

however, it has moved WSW

You think 96E has a big enough circulation to affect the steering of Carlos?