ATL : TROPICAL DEPRESSION IDA

[Ivanhater]

UNCLAS//N03146//
WTNT21 KNGU 032000Z
MSGID/GENADMIN/NAVMARFCSTCEN NORFOLK VA//
SUBJ/TROPICAL CYCLONE FORMATION ALERT 032000Z NOV 09//
RMKS/1. FORMATION OF A TROPICAL CYCLONE IS POSSIBLE WITHIN 100NM
EITHER SIDE OF A LINE FROM 10.4N 81.2W TO 12.5N 83.6W WITHIN THE
NEXT 24 HOURS. AVAILABLE DATA DOES NOT JUSTIFY ISSUANCE OF A
NUMBERED TROPICAL CYCLONE WARNING AT THIS TIME.
2. REMARKS: A LOW PRESSURE CENTER IS LOCATED NEAR 10.0N 81.0W WITH ESTIMATED
WINDS OF 20 KNOTS AND IS CURRENTLY TRACKING WEST-NORTHWEST AT 5 TO 10
KNOTS. VISIBLE SATELLITE IMAGERY INDICATES THAT THIS SYSTEM IS
SLOWLY BECOMING BETTER ORGANIZED DUE TO ANTI-CYCLONIC FLOW ALOFT,
WARM SEA SURFACE TEMPERATURES AND VERY MINIMAL WIND SHEAR.
3. THIS ALERT WILL BE REISSUED, CANCELLED, OR EXPIRE BY 042000Z NOV
2009.//

[HURAKAN]

Latest

[cycloneye]

Latest microwave image shows spiral banding forming.

Microwave image

[Derek Ortt]

link isn't working for me. Getting a not found error

[leanne_uk]

yes me too. Gettin an error on the link

[HURAKAN]

03/1745 UTC 10.3N 81.1W T1.5/1.5 97L

Not bad!

[tolakram]

[cycloneye]

For a second run in a row,GFDL at the 18z run crawls it northward as a cat 3 cane.See loop below.

http://moe.met.fsu.edu/cgi-bin/gfdltc2. ... =Animation



975
WHXX04 KWBC 032319
CHGQLM
ATTENTION...NATIONAL HURRICANE CENTER

NCEP COUPLED GFDL HURRICANE MODEL FORECAST MADE FOR

TROPICAL DEPRESSION INVEST 97L

INITIAL TIME 18Z NOV 3

DISCLAIMER ... THIS INFORMATION IS PROVIDED AS GUIDANCE. IT
REQUIRES INTERPRETATION BY HURRICANE SPECIALISTS AND SHOULD
NOT BE CONSIDERED AS A FINAL PRODUCT. PLEASE SEE THE TPC/NHC
OFFICIAL FORECAST.


FORECAST STORM POSITION

HOUR LATITUDE LONGITUDE HEADING/SPEED(KT)

0 10.5 81.2 325./ 1.9
6 10.5 81.3 292./ 1.6
12 10.6 81.3 351./ .6
18 11.2 81.5 344./ 6.0
24 11.5 81.9 305./ 5.0
30 11.6 82.4 288./ 4.7
36 11.6 82.8 272./ 3.6
42 11.9 82.6 36./ 2.8
48 12.1 82.4 29./ 3.1
54 12.3 82.4 22./ 1.8
60 12.5 82.0 56./ 3.9
66 12.7 81.8 61./ 3.0
72 13.0 81.5 39./ 4.4
78 13.3 81.3 27./ 3.6
84 13.5 81.1 53./ 3.1
90 13.8 81.0 19./ 3.1
96 14.1 80.8 27./ 2.9
102 14.6 80.9 349./ 5.6
108 15.1 80.9 6./ 4.4
114 15.6 80.9 359./ 5.4
120 16.3 81.0 349./ 6.7
126 16.8 81.4 326./ 6.8

[wxman57]

I've been monitoring obs in the region and don't see much change. Still haven't found any over about 10-12 kts. There is an LLC, but the main circulation appears to be aloft, thus the higher Dvorak number. I do think that there's a bit greater than 50% shot at this becoming Ida, but I think it's most likely to move inland into Central America and/or Mexico where it would dissipate.

[cycloneye]

Code Orange


TROPICAL WEATHER OUTLOOK
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
700 PM EST TUE NOV 3 2009

FOR THE NORTH ATLANTIC...CARIBBEAN SEA AND THE GULF OF MEXICO...

CLOUDINESS AND SHOWERS ASSOCIATED WITH AN AREA OF LOW PRESSURE IN
THE EXTREME SOUTHWESTERN CARIBBEAN SEA CONTINUE TO SHOW SIGNS OF
ORGANIZATION. THE LOW IS EXPECTED TO MOVE LITTLE OVER THE NEXT DAY
OR SO...AND UPPER-LEVEL WINDS ARE FAVORABLE FOR SOME ADDITIONAL
DEVELOPMENT. THERE IS A MEDIUM CHANCE...30 TO 50 PERCENT...OF THIS
SYSTEM BECOMING A TROPICAL CYCLONE DURING THE NEXT 48 HOURS.
LOCALLY HEAVY RAINS ARE POSSIBLE OVER THE NEXT FEW DAYS OVER
PORTIONS OF PANAMA...COSTA RICA...NICARAGUA...AND HONDURAS IN
ASSOCIATION WITH THIS SYSTEM.

ELSEWHERE...TROPICAL CYCLONE FORMATION IS NOT EXPECTED DURING THE
NEXT 48 HOURS.

$$
FORECASTER PASCH

[cycloneye]

18z HWRF is more stronger than the 12z run as it has a strong tropical storm in the Western Caribbean.

http://moe.met.fsu.edu/cgi-bin/hwrftc2. ... =Animation

[Ivanhater]

[ozonepete]

Looks like a no-brainer on this getting to TS status. It has SSTs around 29C, good mid-level mositure, and little to no shear at all over it (and it's stationary under that low shear area for a day or two). The OHC may be borderline there, but OHC doesn't come into play for a developing TS anyway - it's the SSTs that matter. The conditions that will steer it and decide its strength a few days from now are not in place at all yet, so it's too early to say. But will this be a TS? Hello, TS Ida.

[Ivanhater]

I've been monitoring obs in the region and don't see much change. Still haven't found any over about 10-12 kts. There is an LLC, but the main circulation appears to be aloft, thus the higher Dvorak number. I do think that there's a bit greater than 50% shot at this becoming Ida, but I think it's most likely to move inland into Central America and/or Mexico where it would dissipate.

I'm very cautious with that solution at this time, with the Canadian, GFDL, and HWRF keeping this offshore. And looking at the setup from the Euro, I am seeing a clear weakness in the gulf that could[i][/i] allow this from being pushed into Central America.

What is very hard to ignore is the strong model agreement here. I agree with this threat being greater than 50 percent.

[cycloneye]

SHIP intensity in a weak status has not changed since the first run this morning as it tracks thru land,distint from other models like GFDL,HWRF and UKMET that avoid land and have a stronger system.

WHXX01 KWBC 040018
CHGHUR
TROPICAL CYCLONE GUIDANCE MESSAGE
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
0018 UTC WED NOV 4 2009

DISCLAIMER...NUMERICAL MODELS ARE SUBJECT TO LARGE ERRORS.
PLEASE REFER TO NHC OFFICIAL FORECASTS FOR TROPICAL CYCLONE
AND SUBTROPICAL CYCLONE INFORMATION.

ATLANTIC OBJECTIVE AIDS FOR

DISTURBANCE INVEST (AL972009) 20091104 0000 UTC

...00 HRS... ...12 HRS... ...24 HRS. .. ...36 HRS...
091104 0000 091104 1200 091105 0000 091105 1200

LAT LON LAT LON LAT LON LAT LON
BAMS 10.4N 80.9W 11.1N 81.6W 11.8N 82.4W 12.5N 83.1W
BAMD 10.4N 80.9W 11.1N 81.3W 11.9N 81.9W 13.0N 82.7W
BAMM 10.4N 80.9W 11.2N 81.3W 12.0N 82.0W 12.9N 82.6W
LBAR 10.4N 80.9W 11.1N 81.3W 12.3N 82.0W 13.8N 82.7W
SHIP 25KTS 27KTS 29KTS 32KTS
DSHP 25KTS 27KTS 29KTS 32KTS

...48 HRS... ...72 HRS... ...96 HRS. .. ..120 HRS...
091106 0000 091107 0000 091108 0000 091109 0000

LAT LON LAT LON LAT LON LAT LON
BAMS 13.1N 83.9W 14.4N 85.6W 16.2N 87.2W 17.9N 89.6W
BAMD 14.1N 83.3W 16.4N 83.9W 19.2N 84.1W 21.7N 83.7W
BAMM 13.8N 83.3W 15.4N 84.7W 17.6N 86.1W 19.5N 87.7W
LBAR 15.2N 83.2W 17.0N 82.7W 17.3N 80.9W 17.9N 79.4W
SHIP 34KTS 34KTS 34KTS 30KTS
DSHP 34KTS 28KTS 29KTS 24KTS

...INITIAL CONDITIONS...
LATCUR = 10.4N LONCUR = 80.9W DIRCUR = 0DEG SPDCUR = 0KT
LATM12 = 10.1N LONM12 = 81.1W DIRM12 = 342DEG SPDM12 = 2KT
LATM24 = 9.9N LONM24 = 80.8W
WNDCUR = 25KT RMAXWD = 25NM WNDM12 = 25KT
CENPRS = 1007MB OUTPRS = 1010MB OUTRAD = 150NM SDEPTH = M
RD34NE = 0NM RD34SE = 0NM RD34SW = 0NM RD34NW = 0NM

[gatorcane]

Both the 18Z GFDL and HWRF are in agreement on a general NNW to North movement over the next 5 days or so with strengthening in the Western Caribbean. That movement seems reasonable to me and that is the forecast I have gone with since yesterday. The GFDL is stronger initially since it keeps it over water. That means that these models are not forecasting the shear to be strong at all as it moves north with favorable conditions once in the Western Caribbean.

The 12Z ECMWF and 12Z GFS move it more to the left of the GFDL and HWRF with it bending west near or into the Yucatan/Belize. It will be interesting to see if the GFS/ECMWF joing the GFDL/HWRF or visa-versa. When I look at the GFDL and HWRF, I see a pretty decent area of high pressure sitting over the Eastern CONUS, over the Ohio river-valley area by day 5. That could mean a more WNW bend in the Western Caribbean....

Perhaps the GFDL/HWRF send it poleward because they both forecast a deeper system than the GFS/ECMWF. I recall an ECMWF run yesterday with a deeper system heading more right than what the ECMWF showed today in the 12Z.

[Ivanhater]

Both the 18Z GFDL and HWRF are in agreement on a general NNW to North movement over the next 5 days or so with strengthening in the Western Caribbean. The GFDL is stronger initially since it keeps it over water. That means that these models are not forecasting the shear to be strong at all as it moves north.

The 12Z ECMWF and 12Z GFS move it more to the left of the GFDL and HWRF with it bending west near or into the Yucatan/Belize. It will be interesting to see if the GFS/ECMWF joing the GFDL/HWRF or visa-versa. When I look at the GFDL and HWRF, I see a pretty decent area of high pressure sitting over the Eastern CONUS, over the Ohio river-valley area. That could mean a more WNW bend in the Western Caribbean....

Perhaps the GFDL/HWRF send it poleward because they both forecast a deeper system than the GFDL/ECMWF.

Most of the models are showing favorable conditions for strengthening, most notably the Euro and GFDL. With the water temps in that region, people need to keep a close eye on it.

BTW, this is the reason people cannot say the season is over until its over. Still plenty of crow left over for thanksgiving.

[wxman57]

I've been monitoring obs in the region and don't see much change. Still haven't found any over about 10-12 kts. There is an LLC, but the main circulation appears to be aloft, thus the higher Dvorak number. I do think that there's a bit greater than 50% shot at this becoming Ida, but I think it's most likely to move inland into Central America and/or Mexico where it would dissipate.

I'm very cautious with that solution at this time, with the Canadian, GFDL, and HWRF keeping this offshore. And looking at the setup from the Euro, I am seeing a clear weakness in the gulf that could[i][/i] allow this from being pushed into Central America.

What is very hard to ignore is the strong model agreement here. I agree with this threat being greater than 50 percent.

Well, the GFDL and HWRF haven't proven to be very trustworthy this season. I see the new GFDL only takes it to 17N/81W in 5 days, 4 deg farther south than the last run. Canadian track may not be too bad (a bit east of GFS), but it seems to have a hard time discerning the impact of shear on a tropical cyclone.

Surface obs this evening don't indicate any better organization. There's an LLC, but it is still very weak. The 25 kts in the model initialization may be a bit generous. It certainly doesn't appear to represent the average wind speeds around the low center. And convection is having a hard time maintaining itself. Without that, it can't deepen and develop.

Here's a 00Z analysis:

[HURAKAN]

03/2345 UTC 10.4N 80.9W T1.5/1.5 97L

No change

[ozonepete]

I've been monitoring obs in the region and don't see much change. Still haven't found any over about 10-12 kts. There is an LLC, but the main circulation appears to be aloft, thus the higher Dvorak number. I do think that there's a bit greater than 50% shot at this becoming Ida, but I think it's most likely to move inland into Central America and/or Mexico where it would dissipate.

I'm very cautious with that solution at this time, with the Canadian, GFDL, and HWRF keeping this offshore. And looking at the setup from the Euro, I am seeing a clear weakness in the gulf that could[i][/i] allow this from being pushed into Central America.

What is very hard to ignore is the strong model agreement here. I agree with this threat being greater than 50 percent.

Well, the GFDL and HWRF haven't proven to be very trustworthy this season. I see the new GFDL only takes it to 17N/81W in 5 days, 4 deg farther south than the last run. Canadian track may not be too bad (a bit east of GFS), but it seems to have a hard time discerning the impact of shear on a tropical cyclone.

Surface obs this evening don't indicate any better organization. There's an LLC, but it is still very weak. The 25 kts in the model initialization may be a bit generous. It certainly doesn't appear to represent the average wind speeds around the low center. And convection is having a hard time maintaining itself. Without that, it can't deepen and develop.

Here's a 00Z analysis:

Convection re-developing over the center for the second time in less than 6 hours. And the satellite loops have shown a considerably strong mid-level circulation for how long now? In the kind of environment this is in, these are pretty good indicators that a very viable, deep center is forming. With enough continuous pulling up at the mid and upper levels, the lower levels will come along...