ATL: MARIA - Post-Tropical - Discussion

[Aric Dunn]

Looks to be organizing quite quickly and moving around 280. Dont think this will last long as a TD... TS by morning. outflow established and already see a decent curved band wrapping around with convection firing centrally over the center. at about 11.5N 36.2W

[LarryWx]

yes the 00z run after 168 hours had a more progressive trough which let the trough in the 12z run to pass by and kept it on the wnw heading to the NW carrib. but remember how many run to run consistency issues we just had with the euro for Katia after 144 to 168 hours.. from 12z to 00z it was flip flopping from trough to ridge. but up to the 120 hours the euro was very good and again the 120 to 144 hours difference with the 00z and 12z is very small its after where things change. . and so given the current set up the euro seems the most reasonable..

biggest difference up to 120 hours is the the gulf system this run is much stronger than the 00z run which might be the reason for the stronger trough this run

Aric/others,
As of 2 PM EDT (6 hour map), the 12Z GFS has 95L near 11.5N, 39.5W (and at ~1011 mb) whereas the 12Z Euro has it near 10.0N, 35.5W and slightly stronger at 1010 mb. Also, the 2 AM EDT Wed. 12 Euro position (18 hour Euro map) is almost right on top of the 12Z GFS' 2 PM Tue. (6 hour) map and is ~2 mb stronger. (It is actually ~30 miles south of that GFS map.)

Any opinion on which model is closer to the actual position and actual strength? I think the Euro is clearly closer in position, but want others' opinions.

[gatorcane]

Looks very similar to katia actually looking at the BAMs above.

The 12Z FIM model shows a track nearly identical to Katia:

http://fim.noaa.gov/FIMscp/Welcome.cgi? ... 2011+-+12Z

By the way, NHC track will probably follow the grey line since it is the consensus, which will show a turn to the NW or WNW at the end.

[Aric Dunn]

With this possibly being td14, do you think this is developing a little faster than modeled

no its about right. most of the models have a 1008 to 1010 mb closed low at this time which is TD. none of them how ever strengthen it quickly ... but given the environment and present trend a TS should come sooner rather than later and I do see this intensifying faster than the models are saying.

[HenkL]

BEGIN
NHC_ATCF
invest_al142011.invest
FSTDA
R
U
040
010
0000
201109061840
NONE
NOTIFY=ATRP
END
FOURTEEN, AL, L, , , , , 14, 2011, TD, O, 2011090506, 9999999999, , , , , , METWATCH, 4, AL142011

.....

AL, 14, 2011090618, , BEST, 0, 116N, 362W, 30, 1008, LO, 0, , 0, 0, 0, 0, 1012, 175, 75, 0, 0, L, 0, , 0, 0, FOURTEEN, S,

[cycloneye]

Aric,will that upper low to the NW of the system have an effect?

[Aric Dunn]

yes the 00z run after 168 hours had a more progressive trough which let the trough in the 12z run to pass by and kept it on the wnw heading to the NW carrib. but remember how many run to run consistency issues we just had with the euro for Katia after 144 to 168 hours.. from 12z to 00z it was flip flopping from trough to ridge. but up to the 120 hours the euro was very good and again the 120 to 144 hours difference with the 00z and 12z is very small its after where things change. . and so given the current set up the euro seems the most reasonable..

biggest difference up to 120 hours is the the gulf system this run is much stronger than the 00z run which might be the reason for the stronger trough this run

Aric/others,
As of 2 PM EDT (6 hour map), the 12Z GFS has 95L near 11.5N, 39.5W (and at ~1011 mb) whereas the 12Z Euro has it near 10.0N, 35.5W and slightly stronger at 1010 mb. Also, the 2 AM EDT Wed. 12 Euro position (18 hour Euro map) is almost right on top of the 12Z GFS' 2 PM Tue. (6 hour) map and is ~2 mb stronger. (It is actually ~30 miles south of that GFS map.)

Any opinion on which model is closer to the actual position and actual strength? I think the Euro is clearly closer in position, but want others' opinions.

39W is way to far west.. Like I was mentioning earlier the GFS and most of the other models are not intializing its position or motion very well the center appears to be about 36.2 W and 11.5 North. so its basically the Euro is better on lon and gfs better on lat. but the GFS is too fast to turn because it has a much weaker current ridge.

[Aric Dunn]

Aric,will that upper low to the NW of the system have an effect?

well i have been watching it and in the short term its not having a effect... right now it seems the upper environment is being influenced by a upper trough to its north that is helping venting it... which should continue for the next 36 hrs or so.. after which it looks like northerly flow from Katia and that upper low may affect it. but that ULL should basically follow KATIA out of the way. the timing will be key of course.

[gatorcane]

NWS Miami snippet from 2:35 pm EST discussion. Looks like they are not buying the GFS and other models that take it well east of Florida and the Bahamas.

It's interesting they keep mentioning it as they are usually a conservative group that waits until absolutely necessary to talk about any tropical threats...

THE LONG RANGE MODELS ARE STILL SHOWING THE VIGOROUS TROPICAL
WAVE OVER THE EASTERN ATLANTIC WATERS TO MOVE TO THE WEST
NORTHWEST AND BE APPROACHING THE SOUTHERN BAHAMA ISLANDS EARLY
NEXT WEEK. FLORIDA RESIDENTS AND VISITORS NEED TO CONTINUE TO
MONITOR THE LATEST FORECAST FROM THE NATIONAL HURRICANE CENTER ON
THIS VIGOROUS TROPICAL WAVE THROUGH THE WEEK.

http://forecast.weather.gov/product.php ... glossary=1

[gatorcane]

it doesn't look like 95L is gaining much lattitude today, more west than WNW.....

Katia was well on a WNW track by now so not sure I am going to believe the FIM or GFS at this point.

Going to be interesting to see the next set of model runs when they initialize position and strength properly.

[Gustywind]

Given NRL ...
20110906.1915.14LFOURTEEN.25kts-1009mb-112N-344W

[AdamFirst]

Things will get much more clearer when the models have a legit center to digest.

[gatorcane]

Using this floater loop and clicking on LAT/LON, I don't see any lattitude gain today so far. Due west...

http://www.ssd.noaa.gov/goes/flt/t3/loop-vis.html

[cycloneye]

Using this floater loop and clicking on LAT/LON, I don't see any lattitude gain today so far. Due west...

http://www.ssd.noaa.gov/goes/flt/t3/loop-vis.html

West and moving fast.

[HurricaneMaster_PR]

TAFB Surface Forecast 72 hrs

[Aric Dunn]

NWS Miami snippet from 2:35 pm EST discussion. Looks like they are not buying the GFS and other models that take it well east of Florida and the Bahamas.

It's interesting they keep mentioning it as they are usually a conservative group that waits until absolutely necessary to talk about any tropical threats...

THE LONG RANGE MODELS ARE STILL SHOWING THE VIGOROUS TROPICAL
WAVE OVER THE EASTERN ATLANTIC WATERS TO MOVE TO THE WEST
NORTHWEST AND BE APPROACHING THE SOUTHERN BAHAMA ISLANDS EARLY
NEXT WEEK. FLORIDA RESIDENTS AND VISITORS NEED TO CONTINUE TO
MONITOR THE LATEST FORECAST FROM THE NATIONAL HURRICANE CENTER ON
THIS VIGOROUS TROPICAL WAVE THROUGH THE WEEK.

http://forecast.weather.gov/product.php ... glossary=1

well they are right next door to the NHC.. lol maybe a indication of the NHC thinking as well... besides the EUro is the only model I have seen that accurately initializes the present synoptic setup.. They could be leaning that way.

[LarryWx]

Given NRL ...
20110906.1915.14LFOURTEEN.25kts-1009mb-112N-344W

34.4 W at 1915Z? The 12Z GFS has it all the way to 39.5W at 1800 Z. So, IF this is accurate, that would mean the GFS is more than 5 degrees too far west

However, I suspect that as Aric and other posts suggest, it is really near 36.2W and not 34.4W meaning the 12Z GFS is only about 3 degrees too far west.

[Aric Dunn]

Given NRL ...
20110906.1915.14LFOURTEEN.25kts-1009mb-112N-344W

34.4 W at 1915Z? The 12Z GFS has it all the way to 39.5W at 1800 Z. So, IF this is accurate, that would mean the GFS is more than 5 degrees too far west

However, I suspect that as Aric and other posts suggest, it is really near 36.2W and not 34.4W meaning the 12Z GFS is only about 3 degrees too far west.

3 degress is still a good deal off.

[fci]

NWS Miami talking about a system that far away puts up some red flags to me.

[CronkPSU]

must be getting ready to rename...it has suddenly disappeared off the map up top!