EAST COAST : Tropical Depression ONE

[HURAKAN]

New storms trying to pop.

[wxman57]

Convection is separating further from the LLC now (center is 60 miles NW of convection), and cloud tops are much warmer than this morning. Definitely weakening now. No upgrade.

[KWT]

Yeah I did notice that on the longer loops wxman57 but the Dvorak numbers are still rising and I think in this case if we do get a reading of 2.5 then I can imagine we may get an upgrade, esp with reagrds to how sharp they were at upgrading this in the first place.

[CrazyC83]

I don't see upgrading until 11 pm at the earliest.

[wxman57]

Yeah I did notice that on the longer loops wxman57 but the Dvorak numbers are still rising and I think in this case if we do get a reading of 2.5 then I can imagine we may get an upgrade, esp with reagrds to how sharp they were at upgrading this in the first place.

I think that the Dvorak estimates are assuming its more vertically stacked than it is. I see absolutely no evidence that it has 39 mph winds. 30 mph may be pushing it.

[cycloneye]

CI keeps creeping up.


UW - CIMSS
ADVANCED DVORAK TECHNIQUE
ADT-Version 7.2.3
Tropical Cyclone Intensity Algorithm

----- Current Analysis -----
Date : 28 MAY 2009 Time : 191500 UTC
Lat : 37:45:16 N Lon : 69:58:40 W


CI# /Pressure/ Vmax
2.2 /1007.4mb/ 32.0kt


Final T# Adj T# Raw T#
(3hr avg)
2.2 2.4 3.0

Latitude bias adjustment to MSLP : +0.0mb

Center Temp : -31.6C Cloud Region Temp : -35.7C

Scene Type : CURVED BAND with 0.58 ARC in MD GRAY

Positioning Method : FORECAST INTERPOLATION

Ocean Basin : ATLANTIC
Dvorak CI > MSLP Conversion Used : ATLANTIC

Tno/CI Rules : Constraint Limits : 0.2T/hour
Weakening Flag : OFF
Rapid Dissipation Flag : OFF

[wxman57]

I don't see upgrading until 11 pm at the earliest.

A big problem with a night upgrade of a system like this is that it'll be very difficult to locate the center. Squalls may flare up significantly tonight but be located 100 or more miles from the weak center. It may look impressive but it wouldn't mean it's a TS if squalls are well-removed from the LLC. I think it's already past the point of making it to a TS. SSTs are cooler and cooler now, and wind shear will be increasing soon (if not already). Of course, I though it was dead last night.

[Cookie]

I wasn't expecting anything else to happen. mother nature dose what she want's we just watch.

[wxman57]

Here's a screenshot of TD One showing the center location northwest of the convection. No ships or buoys in the area:

[HURAKAN]

That's why RECON is invaluable. I think last year no one expected Marco to have TS winds because it was so little. Many times we have seen disturbances or TDs that Dvorak was not showing TS intensity and RECON has found storms.

[tolakram]

Is the center location certain?

[KWT]

Yep wxman57 no doubt the convection is located away from the center, and convection doesn't seem quite as impressive now. If it was upto me I'm not sure I'd upgrade it but the NHc may well do, we have to wait and see.

[cycloneye]

WTNT31 KNHC 282031
TCPAT1
BULLETIN
TROPICAL DEPRESSION ONE ADVISORY NUMBER 2
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL012009
500 PM AST THU MAY 28 2009

...DEPRESSION MOVING NORTHEASTWARD OVER THE OPEN ATLANTIC...

AT 500 PM AST...2100 UTC...THE CENTER OF TROPICAL DEPRESSION ONE WAS
LOCATED NEAR LATITUDE 37.7 NORTH...LONGITUDE 69.4 WEST OR ABOUT
305 MILES...485 KM...SOUTH-SOUTHEAST OF PROVIDENCE RHODE ISLAND AND
ABOUT 565 MILES...905 KM...SOUTHWEST OF HALIFAX NOVA SCOTIA.

THE DEPRESSION IS MOVING TOWARD THE NORTHEAST NEAR 16 MPH...
26 KM/HR...AND A GENERAL MOTION TOWARD THE EAST-NORTHEAST IS
EXPECTED OVER THE NEXT 24 TO 48 HOURS. THE DEPRESSION IS NOT
EXPECTED TO THREATEN ANY LAND AREAS.

MAXIMUM SUSTAINED WINDS ARE NEAR 35 MPH...55 KM/HR...WITH HIGHER
GUSTS. THE DEPRESSION COULD BECOME A TROPICAL STORM TONIGHT OR
FRIDAY...BUT THEN IS EXPECTED TO WEAKEN OR DISSIPATE OVER COLDER
WATERS BY SATURDAY.

ESTIMATED MINIMUM CENTRAL PRESSURE IS 1006 MB...29.71 INCHES.

...SUMMARY OF 500 PM AST INFORMATION...
LOCATION...37.7N 69.4W
MAXIMUM SUSTAINED WINDS...35 MPH
PRESENT MOVEMENT...NORTHEAST OR 55 DEGREES AT 16 MPH
MINIMUM CENTRAL PRESSURE...1006 MB

THE NEXT ADVISORY WILL BE ISSUED BY THE NATIONAL HURRICANE CENTER AT
1100 PM AST.

$$
FORECASTER BEVEN

000
WTNT41 KNHC 282031
TCDAT1
TROPICAL DEPRESSION ONE DISCUSSION NUMBER 2
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL012009
500 PM AST THU MAY 28 2009

CONVECTION ASSOCIATED WITH TROPICAL DEPRESSION ONE HAS DECREASED
SOMEWHAT THIS AFTERNOON AND IS NOW LIMITED TO THE SOUTHEASTERN
QUADRANT. SATELLITE INTENSITY ESTIMATES FROM TAFB AND SAB ARE
30 KT...WHICH REMAINS THE INITIAL INTENSITY. THE FORECAST TRACK
KEEPS THE CENTER OVER THE GULF STREAM FOR THE NEXT 6-12 HR IN A
LIGHT SHEAR ENVIRONMENT...SO SOME SLIGHT STRENGTHENING COULD OCCUR
DURING THAT TIME AS SHOWN BY THE SHIPS MODEL. AFTER THAT...COLDER
SEA SURFACE TEMPERATURES AND INCREASING SHEAR SHOULD CAUSE
WEAKENING. THE CYCLONE IS EXPECTED TO BECOME EXTRATROPICAL BY
36 HR AND DISSIPATE COMPLETELY AFTER 48 HR. IT IS POSSBLE THAT BOTH
OF THESE EVENTS COULD HAPPEN EARLIER THAN CURRENTLY FORECAST.

THE INITIAL MOTION IS 055/14. THE DEPRESSION IS EMBEDDED IN THE
WESTERLIES BETWEEN THE SUBTROPICAL RIDGE TO THE SOUTHEAST AND A
DEEP-LAYER TROUGH OVER THE EASTERN UNITED STATES AND EASTERN
CANADA. THIS PATTERN SHOULD STEER THE CYCLONE GENERALLY
EAST-NORTHEASTWARD UNTIL DISSIPATION.

FORECAST POSITIONS AND MAX WINDS

INITIAL 28/2100Z 37.7N 69.4W 30 KT
12HR VT 29/0600Z 38.7N 67.0W 35 KT
24HR VT 29/1800Z 40.4N 62.8W 30 KT
36HR VT 30/0600Z 42.2N 57.5W 25 KT...EXTRATROPICAL
48HR VT 30/1800Z 43.9N 52.5W 25 KT...EXTRATROPICAL
72HR VT 31/1800Z...DISSIPATED

$$
FORECASTER BEVEN

[jinftl]

Pressure down 1mb at 5pm....still a td at 35mph...forecast still leaves window for upgrade to ts:

THE FORECAST TRACK
KEEPS THE CENTER OVER THE GULF STREAM FOR THE NEXT 6-12 HR IN A
LIGHT SHEAR ENVIRONMENT...SO SOME SLIGHT STRENGTHENING COULD OCCUR
DURING THAT TIME AS SHOWN BY THE SHIPS MODEL

[cycloneye]

CI still creeping up now to 2.3


UW - CIMSS
ADVANCED DVORAK TECHNIQUE
ADT-Version 7.2.3
Tropical Cyclone Intensity Algorithm

----- Current Analysis -----
Date : 28 MAY 2009 Time : 194500 UTC
Lat : 37:49:16 N Lon : 69:50:00 W


CI# /Pressure/ Vmax
2.3 /1006.6mb/ 33.0kt


Final T# Adj T# Raw T#
(3hr avg)
2.3 2.7 2.7

Latitude bias adjustment to MSLP : +0.0mb

Center Temp : -21.7C Cloud Region Temp : -34.6C

Scene Type : CURVED BAND with 0.46 ARC in MD GRAY

Positioning Method : FORECAST INTERPOLATION

Ocean Basin : ATLANTIC
Dvorak CI > MSLP Conversion Used : ATLANTIC

Tno/CI Rules : Constraint Limits : NO LIMIT
Weakening Flag : OFF
Rapid Dissipation Flag : OFF

[Lurker]

Ana at 11 PM?

CI still creeping up now to 2.3


UW - CIMSS
ADVANCED DVORAK TECHNIQUE
ADT-Version 7.2.3
Tropical Cyclone Intensity Algorithm

----- Current Analysis -----
Date : 28 MAY 2009 Time : 194500 UTC
Lat : 37:49:16 N Lon : 69:50:00 W


CI# /Pressure/ Vmax
2.3 /1006.6mb/ 33.0kt


Final T# Adj T# Raw T#
(3hr avg)
2.3 2.7 2.7

Latitude bias adjustment to MSLP : +0.0mb

Center Temp : -21.7C Cloud Region Temp : -34.6C

Scene Type : CURVED BAND with 0.46 ARC in MD GRAY

Positioning Method : FORECAST INTERPOLATION

Ocean Basin : ATLANTIC
Dvorak CI > MSLP Conversion Used : ATLANTIC

Tno/CI Rules : Constraint Limits : NO LIMIT
Weakening Flag : OFF
Rapid Dissipation Flag : OFF

[HURAKAN]

TD 1 may have a small window to intensify during the extratropical transition process.

[jinftl]

If it's going to become Ana, it really will have to do it by morning at the latest....time is running out....but this system has shown itself to be a bit tenacious and underestimated so i wouldn't rule it out quite yet....it is over the Gulf Stream still and shear is low.

[WmE]

If it's going to become Ana, it really will have to do it by morning at the latest....time is running out....but this system has shown itself to be a bit tenacious and underestimated so i wouldn't rule it out quite yet....it is over the Gulf Stream still and shear is low.

Yeah. Also if it were to be named it'd be the third consecutive season with a named storm before June 1.

[jinftl]

If we get one more burst of convection near the center..which isn't impossible given the natural tendency of diurnal bursts of convection followed by a wane...we will have that 3rd-year-in-a-row named storm before June 1.

This would also make it the 4th storm before June 1 in the last 7 years...interesting that in half of the last 6 seasons, we have had activity pre-June 1. That is the probability of a June storm as well.

If it's going to become Ana, it really will have to do it by morning at the latest....time is running out....but this system has shown itself to be a bit tenacious and underestimated so i wouldn't rule it out quite yet....it is over the Gulf Stream still and shear is low.

Yeah. Also if it were to be named it'd be the third consecutive season with a named storm before June 1.