ATL: TROPICAL STORM BILL (03L)

[shah8]

/me eyes deltadog's placement, then the NHC's placement....

One thing for sure, I will be shouting Hallelujah! when there is a nice, obvious eye to track.

[Meso]

06z models shifted right, but they have straightened out northwards at the end of the run.

Models continuing to flip flop.

[deltadog03]

Got up for a few mins here. Stupid weather.. ha Looking at latest sat pic, I still see it almost charging due west for the time being. I still do no believe the models are handeling the short term movement very well, but its gonna be hard to really tell if that makes much difference in the end game.

[KWT]

Still looks roughly 285 right now looking at the loops and all the data. Also does rather look like Bill is about to bust out a huge eye, will be interesting to watch this.

Got to say this doesn't look great for the Atlantic Canada at the moment and certainly can't rule out a NE US hit either yet IMO.

[Thunder44]

000
WTNT33 KNHC 180834
TCPAT3
BULLETIN
HURRICANE BILL ADVISORY NUMBER 12
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL032009
500 AM AST TUE AUG 18 2009

...BILL MOVING WEST-NORTHWESTWARD ACROSS THE TROPICAL ATLANTIC WITH
LITTLE CHANGE IN STRENGTH...

INTERESTS IN THE LEEWARD ISLANDS SHOULD MONITOR THE PROGRESS OF
BILL.

FOR STORM INFORMATION SPECIFIC TO YOUR AREA IN THE UNITED
STATES...INCLUDING POSSIBLE INLAND WATCHES AND WARNINGS...PLEASE
MONITOR PRODUCTS ISSUED BY YOUR LOCAL NATIONAL WEATHER SERVICE
FORECAST OFFICE. FOR STORM INFORMATION SPECIFIC TO YOUR AREA
OUTSIDE OF THE UNITED STATES...PLEASE MONITOR PRODUCTS ISSUED
BY YOUR NATIONAL METEOROLOGICAL SERVICE.

AT 500 AM AST...0900 UTC...THE CENTER OF HURRICANE BILL WAS LOCATED
NEAR LATITUDE 15.5 NORTH...LONGITUDE 49.7 WEST OR ABOUT 810 MILES...
1305 KM...EAST OF THE LEEWARD ISLANDS.

BILL IS MOVING TOWARD THE WEST-NORTHWEST NEAR 17 MPH...28 KM/HR...
AND THIS MOTION IS EXPECTED TO CONTINUE FOR THE NEXT DAY OR TWO WITH
A GRADUAL TURN TO THE NORTHWEST ON WEDNESDAY.

MAXIMUM SUSTAINED WINDS ARE NEAR 100 MPH...160 KM/HR...WITH HIGHER
GUSTS. BILL IS A CATEGORY TWO HURRICANE ON THE SAFFIR-SIMPSON
SCALE. STRENGTHENING IS FORECAST DURING THE NEXT 48 HOURS...AND
BILL COULD BECOME A MAJOR HURRICANE WITHIN THE NEXT DAY OR SO.

HURRICANE FORCE WINDS EXTEND OUTWARD UP TO 30 MILES...45 KM...FROM
THE CENTER...AND TROPICAL STORM FORCE WINDS EXTEND OUTWARD UP TO 150
MILES...240 KM.

ESTIMATED MINIMUM CENTRAL PRESSURE IS 967 MB...28.56 INCHES.

...SUMMARY OF 500 AM AST INFORMATION...
LOCATION...15.5N 49.7W
MAXIMUM SUSTAINED WINDS...100 MPH
PRESENT MOVEMENT...WEST-NORTHWEST OR 285 DEGREES AT 17 MPH
MINIMUM CENTRAL PRESSURE...967 MB

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

$$
FORECASTER BEVEN


000
WTNT43 KNHC 180837
TCDAT3
HURRICANE BILL DISCUSSION NUMBER 12
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL032009
500 AM AST TUE AUG 18 2009

TRMM DATA FROM 0223 UTC AND RECENT INFRARED IMAGERY SUGGEST THAT
BILL IS UNDERGOING AN EYEWALL REPLACEMENT CYCLE...WITH THE COLDEST
CLOUD TOPS CURRENTLY IN THE OUTER CONVECTIVE RING. SATELLITE
INTENSITY ESTIMATES REMAIN 90 KT FROM SAB AND 77 KT FROM TAFB. THE
INITIAL INTENSITY IS 85 KT...AND THIS COULD BE GENEROUS DUE TO THE
EYEWALL REPLACEMENT.

THE INITIAL MOTION IS 285/15. BILL IS ON THE SOUTH SIDE OF A
LOW/MID-LEVEL RIDGE...WHICH SHOULD STEER THE HURRICANE GENERALLY
WEST-NORTHWESTWARD FOR THE NEXT COUPLE OF DAYS. AFTER THAT...THE
LARGE-SCALE MODELS FORECAST THE RIDGE TO WEAKEN AS A SERIES OF
TROUGHS MOVE THROUGH THE WESTERN ATLANTIC AND THE EASTERN UNITED
STATES. ONE MID/UPPER-LEVEL TROUGH IS CURRENTLY NORTHEAST OF
BERMUDA...MOVING SOUTHWARD. A SECOND MID/UPPER-LEVEL TROUGH IS
ALONG THE EAST COAST OF THE UNITED STATES...FORECAST TO MOVE
EASTWARD AND THEN SOUTHWARD. FINALLY...A STRONG DEEP-LAYER TROUGH
IS FORECAST TO DEVELOP OVER THE EASTERN UNITED STATES BETWEEN
72-120 HR. ALL TRACK GUIDANCE INDICATES THAT BILL SHOULD TURN
NORTHWARD IN RESPONSE TO THE TROUGHS...BUT THERE IS SOME NOTABLE
SPREAD IN WHERE AND WHEN. THE ECMWF...GFS...GFS ENSEMBLE MEAN...
AND THE BAM MODELS TURN BILL NORTHWARD BETWEEN 62W-65W IN RESPONSE
TO THE FIRST TWO TROUGHS. THE REMAINDER OF THE TRACK GUIDANCE
CALLS FOR THE NORTHWARD TURN BETWEEN 65W-70W...DUE TO LESS RESPONSE
TO THE FIRST TWO TROUGHS AND THE EVENTUAL EFFECT OF THE THIRD
TROUGH. THE PREVIOUS FORECAST TRACK WAS IN THE WESTERN CLUSTER...
AND THERE IS NO OBVIOUS REASON TO JUMP THE FORECAST TO THE EASTERN
CLUSTER. THEREFORE...THE NEW TRACK IS DOWN THE MIDDLE OF THE
WESTERN GUIDANCE CLUSTER AND SIMILAR TO THE PREVIOUS FORECAST.

BILL IS IN A LIGHT VERTICAL WIND SHEAR ENVIRONMENT...AND THE SEA
SURFACE TEMPERATURES INCREASE ALONG THE FORECAST TRACK. THE
HURRICANE SHOULD INTENSIFY AFTER THE EYEWALL REPLACEMENT CYCLE IS
OVER...WITH ALL GUIDANCE FORECASTING IT TO BECOME A MAJOR
HURRICANE. THE INTENSITY FORECAST CALLS FOR A PEAK INTENSITY OF
110 KT IN 48 HR. AFTER 48 HR...THE LARGE-SCALE MODELS FORECAST
BILL TO ENCOUNTER MODERATE SOUTHERLY OR SOUTHWESTERLY VERTICAL WIND
SHEAR...AND THE INTENSITY FORECAST THUS CALLS FOR GRADUAL WEAKENING
DURING THAT TIME.

FORECAST POSITIONS AND MAX WINDS

INITIAL 18/0900Z 15.5N 49.7W 85 KT
12HR VT 18/1800Z 16.2N 51.7W 90 KT
24HR VT 19/0600Z 17.4N 54.2W 100 KT
36HR VT 19/1800Z 18.9N 56.7W 105 KT
48HR VT 20/0600Z 20.5N 59.0W 110 KT
72HR VT 21/0600Z 24.0N 63.5W 110 KT
96HR VT 22/0600Z 29.5N 67.5W 105 KT
120HR VT 23/0600Z 35.5N 68.0W 100 KT

$$
FORECASTER BEVEN

[KWT]

06z GFS just starting to come out now.

[Cyclenall]

Why is the GOES imagery having so many problems recently? There are missing images at different times, skipping of every other image at times, blackouts, pixelated images, off center NRL images, etc.

It's still trying to pop a stable eye out and is finishing the inner core. It looks better than it has previously.

[Nimbus]

You can see the upper level low just off the DelMarVa that they are talking about starting to drop in around the back side of the ridge in the water vapor imagery. The earlier weakness has missed but is puliing some of Bills outflow up into it.

Bill looks like he slowed his forward motion enough that he might not be able to keep up with the eastern side of the ridge unless his intensification reinforces the ridge and prevents the Delmarva impulse from dropping south of 30N.

[KWT]

That eye still does look rather ragged however it has to be said, quite a large looking eye as well, still we shall see how well it handles today.

[alan1961]

Why is the GOES imagery having so many problems recently? There are missing images at different times, skipping of every other image at times, blackouts, pixelated images, off center NRL images, etc.

It's still trying to pop a stable eye out and is finishing the inner core. It looks better than it has previously.

yep been a bit jittery all morning cyclenall, NRL are a tad behind as usual but Bill looks like he's on track somewhat for now.

[cycloneye]

Any information from the P-3 flying right now?

[weatherSnoop]

000
UZNT13 KWBC 181023
XXAA 68102 99190 70556 04295 99013 27650 05527 00118 26656 05031
92801 20839 05034 85529 18461 06033 70174 09463 03531 50588 05382
05518 40760 14790 07521 30970 30380 03008 25097 40172 02512 20245
531// 35007 88999 77999
31313 09608 80947
61616 NOAA9 WX03A BILL OB 06
62626 SPL 1898N05570W 1001 MBL WND 05031 AEV 20801 DLM WND 05019
012168 WL150 05030 083 REL 1903N05563W 094749 SPG 1898N05569W 100
152 =
XXBB 68108 99190 70556 04295 00013 27650 11930 21031 22863 17250
33850 18461 44828 18664 55818 19474 66797 18271 77681 07462 88632
01440 99612 00157 11598 00271 22579 01074 33557 00277 44393 15579
55292 31579 66249 40372 77212 49966 88189 559//
21212 00013 05527 11004 05031 22916 05035 33874 05528 44850 06033
55620 03033 66540 06515 77495 05019 88466 07520 99388 08022 11318
08012 22296 02506 33248 03013 44233 36018 55215 02013 66206 01011
77179 14510 88176 15512
31313 09608 80947
61616 NOAA9 WX03A BILL OB 06
62626 SPL 1898N05570W 1001 MBL WND 05031 AEV 20801 DLM WND 05019
012168 WL150 05030 083 REL 1903N05563W 094749 SPG 1898N05569W 100
152 =


Here is what I can find Dropsonde

[Thunder44]

Any information from the P-3 flying right now?

They flew out this morning and have been dropping some dropsondes. But so far, they seem to be staying out the storm. This is the last drosponde decoded:

Code: Select all

Product: NOAA Temp Drop (Dropsonde) Message (UZNT13 KWBC)
Transmitted: 18th day of the month at 10:23Z
Aircraft: Gulfstream IV-SP (G-IV) (Reg. Num. N49RF)
Storm Number: 03
Storm Name: Bill (in the North Atlantic basin)
Mission: Non-Tasked Mission
Observation Number: 06

Part A...

Date: Near the closest hour of 10Z on the 18th day of the month
Highest Mandatory Level For Which Wind Was Reported: 200mb
Coordinates: 19.0N 55.6W
Location: 686 miles (1105 km) to the E (87°) from San Juan, Puerto Rico (USA).
Marsden Square: 042 (About)


Level
Geo. Height
Air Temp.
Dew Point
Wind Direction
Wind Speed
1013mb (29.91 inHg)
Sea Level (Surface)
27.6°C (81.7°F)
Approximately 23°C (73°F)
55° (from the NE)
27 knots (31 mph)
1000mb
118m (387 ft)
26.6°C (79.9°F)
Approximately 21°C (70°F)
50° (from the NE)
31 knots (36 mph)
925mb
801m (2,628 ft)
20.8°C (69.4°F)
16.9°C (62.4°F)
50° (from the NE)
34 knots (39 mph)
850mb
1,529m (5,016 ft)
18.4°C (65.1°F)
Approximately 7°C (45°F)
60° (from the ENE)
33 knots (38 mph)
700mb
3,174m (10,413 ft)
9.4°C (48.9°F)
Approximately -4°C (25°F)
35° (from the NE)
31 knots (36 mph)
500mb
5,880m (19,291 ft)
-5.3°C (22.5°F)
Approximately -37°C (-35°F)
55° (from the NE)
18 knots (21 mph)
400mb
7,600m (24,934 ft)
-14.7°C (5.5°F)
Approximately -55°C (-67°F)
75° (from the ENE)
21 knots (24 mph)
300mb
9,700m (31,824 ft)
-30.3°C (-22.5°F)
Reading unavailable when relative humidity is less than 20%
30° (from the NNE)
8 knots (9 mph)
250mb
10,970m (35,991 ft)
-40.1°C (-40.2°F)
Approximately -62°C (-80°F)
25° (from the NNE)
12 knots (14 mph)
200mb
12,450m (40,846 ft)
-53.1°C (-63.6°F)
Reading usually unavailable when air temperature is below -40°C (-40°F)
350° (from the N)
7 knots (8 mph)


Information About Radiosonde:
- Launch Time: 9:47Z
- About Sonde: A descending radiosonde tracked automatically by satellite navigation with no solar or infrared correction.

Remarks Section...
Splash Location: 18.98N 55.7W
Splash Time: 10:01Z

Release Location: 19.03N 55.63W
Release Time: 9:47:49Z

Splash Location: 18.98N 55.69W

Mean Boundary Level Wind (mean wind in the lowest 500 geopotential meters of the sounding):
- Wind Direction: 50° (from the NE)
- Wind Speed: 31 knots (36 mph)

Deep Layer Mean Wind (average wind over the depth of the sounding):
- Wind Direction: 50° (from the NE)
- Wind Speed: 19 knots (22 mph)
- Depth of Sounding: From 168mb to 1012mb

Average Wind Over Lowest Available 150 geopotential meters (gpm) of the sounding:
- Lowest 150m: 158 gpm - 8 gpm (518 geo. feet - 26 geo. feet)
- Wind Direction: 50° (from the NE)
- Wind Speed: 30 knots (35 mph)

Sounding Software Version: AEV 20801

Rest of remarks section: 100 152 (Our system could not determine how to decode this text.)

Part B: Data For Significant Levels...


Significant Temperature And Relative Humidity Levels...
Level
Air Temperature
Dew Point
1013mb (Surface)
27.6°C (81.7°F)
Approximately 23°C (73°F)
930mb
21.0°C (69.8°F)
17.9°C (64.2°F)
863mb
17.2°C (63.0°F)
Approximately 12°C (54°F)
850mb
18.4°C (65.1°F)
Approximately 7°C (45°F)
828mb
18.6°C (65.5°F)
Approximately 5°C (41°F)
818mb
19.4°C (66.9°F)
Approximately -5°C (23°F)
797mb
18.2°C (64.8°F)
Approximately -3°C (27°F)
681mb
7.4°C (45.3°F)
Approximately -5°C (23°F)
632mb
1.4°C (34.5°F)
-2.6°C (27.3°F)
612mb
-0.1°C (31.8°F)
Approximately -7°C (19°F)
598mb
0.2°C (32.4°F)
Approximately -21°C (-6°F)
579mb
1.0°C (33.8°F)
Approximately -23°C (-9°F)
557mb
0.2°C (32.4°F)
Approximately -27°C (-17°F)
393mb
-15.5°C (4.1°F)
Approximately -44°C (-47°F)
292mb
-31.5°C (-24.7°F)
Approximately -60°C (-76°F)
249mb
-40.3°C (-40.5°F)
Approximately -62°C (-80°F)
212mb
-49.9°C (-57.8°F)
Approximately -66°C (-87°F)
189mb
-55.9°C (-68.6°F)
Reading usually unavailable when air temperature is below -40°C (-40°F)



Significant Wind Levels...
Level
Wind Direction
Wind Speed
1013mb (Surface)
55° (from the NE)
27 knots (31 mph)
1004mb
50° (from the NE)
31 knots (36 mph)
916mb
50° (from the NE)
35 knots (40 mph)
874mb
55° (from the NE)
28 knots (32 mph)
850mb
60° (from the ENE)
33 knots (38 mph)
620mb
30° (from the NNE)
33 knots (38 mph)
540mb
65° (from the ENE)
15 knots (17 mph)
495mb
50° (from the NE)
19 knots (22 mph)
466mb
75° (from the ENE)
20 knots (23 mph)
388mb
80° (from the E)
22 knots (25 mph)
318mb
80° (from the E)
12 knots (14 mph)
296mb
25° (from the NNE)
6 knots (7 mph)
248mb
30° (from the NNE)
13 knots (15 mph)
233mb
360° (from the N)
18 knots (21 mph)
215mb
20° (from the NNE)
13 knots (15 mph)
206mb
10° (from the N)
11 knots (13 mph)
179mb
145° (from the SE)
10 knots (12 mph)
176mb
155° (from the SSE)
12 knots (14 mph)

The highest wind observed in the "Significant Wind Levels" section is noted in bold.

---

Dropsonde Diagram:

[caribepr]

Well, I'll go back to sleep when that curve starts really going on...

[cycloneye]

It looks like the ERC is finishing.

[KWT]

Still looks like being a big threat to Bermuda at the moment, also looking at the IR seems like Bill is just about ready to strengthen quite a lot...big eye is starting to get really well developed so today looks like the one where it'll strengthen upto major status.

[Thunder44]

First drop is the one over NOAA symbol. Last drop is the one on the top left:

[alan1961]

Still looks like being a big threat to Bermuda at the moment, also looking at the IR seems like Bill is just about ready to strengthen quite a lot...big eye is starting to get really well developed so today looks like the one where it'll strengthen upto major status.

Better do KWT because my eyes are about blinkin shut with Bill's slow progress

[KWT]

Yeah you can see the eye starting to really improve so I'd think if that starts to clear out we'd be looking at a major. At least we have a decent hurricane at all the talk of a very slow season!

[cycloneye]

Well, I'll go back to sleep when that curve starts really going on...

I am in that camp too Mj.Yes,it passed just north of the 15N-50W box but until it passes the latitud of the most northern island I wont be tranquil.I cant forget Luis (not me but the hurricane) as he loved the 17N line.