ATL: LEE - Remnants - Discussion

[clfenwi]

Lengthy discussion of this system in HPC's model diagnostics discussion

MODEL DIAGNOSTIC DISCUSSION
NWS HYDROMETEOROLOGICAL PREDICTION CENTER CAMP SPRINGS MD
223 PM EDT WED AUG 31 2011

VALID AUG 31/1200 UTC THRU SEP 04/0000 UTC


...DISTURBANCE IN THE GULF OF MEXICO...
PREFERENCE: ENSEMBLE COMPROMISE

FOLLOWING THE SAME TREND AS YESTERDAY...THE NAM REMAINS THE
NORTHERN MOST AND DEEPEST SOLUTION WITH THE LOW PRESSURE SYSTEM IN
THE GULF ON DAY 2. THERE IS LITTLE AGREEMENT AMONGST THE
OPERATIONAL MODELS WITH RESPECT TO THE LOW LOCATION WHEN IT MOVES
INTO THE NORTHERN GULF AND EVENTUALLY ONSHORE. THE 00Z ECMWF AND
CMC TAKE THE LOW INTO TEXAS...BUT THE CMC IS MUCH STRONGER THAN
THE ECMWF. THE 06Z GFS AND 00Z UKMET TAKE THE SYSTEM INTO
LOUISIANA AND MISSISSIPPI...WITH THE UKMET CARRYING THE STRONGER
SOLUTION. THE 12Z NAM STARTS WITH VERY DISORGANIZED SHORTWAVE
ENERGY STRUNG OUT ALONG THE TEXAS...LOUISIANA AND MISSISSIPPI
COASTS AT F48 FRIDAY MORNING...WHICH IS 12 HOURS EARLIER THAN MOST
OTHER OPERATIONAL MODELS INDICATE. THE NAM CONTINUES TO BE ONE OF
THE STRONGEST SOLUTIONS...EVENTUALLY ROTATING THE BULK OF THE
ENERGY WESTWARD INTO EAST TEXAS BY THE END OF THE FORECAST PERIOD.
THE SREF MEAN TENDS TO AGREE WITH THE PLACEMENT OF THE NAM LOW BUT
NOT ON THE STRENGTH...MEANWHILE OTHER ENSEMBLE GUIDANCE LEANS MORE
TOWARDS THE 00Z ECMWF SOLUTION.

THE 12Z GFS HAS SHIFTED THE LOW CENTER TO THE WEST TOWARDS THE 12Z
NAM SOLUTION. THE 12Z GFS HAS ALSO STRENGTHENED FROM THE 06Z
RUN...BUT STILL REMAINS MUCH WEAKER THAN THE NAM. THE 12Z GFS ALSO
PROPAGATES THE LOW CENTER EASTWARD ON DAY 3...WHICH IS THE
OPPOSITE DIRECTION FROM THE 12Z NAM MOVEMENT. THE 12Z UKMET
REMAINS ON THE EAST SIDE OF THE SPREAD WITH THE GFS THROUGH
F48...AND THEN ABRUPTLY CHANGES TRACK AND MOVES TOWARDS THE
CANADIAN/NAM SOLUTION. IN THE SHORT TERM THE 12Z ECMWF HAS TRENDED
SLIGHTLY DEEPER AND EAST OF ITS PREVIOUS TRACK...MOVING ITS
SOLUTION TOWARDS THE NAM CLUSTER.

HOWEVER...WITH THE RIDGE STILL IN PLACE OVER THE SOUTH THAT COULD
IMPACT THE WESTWARD EXTENT OF THIS SYSTEMS MOVEMENT...THE
VARIABILITY OF THE STRENGTH AND TRACK OF THIS SYSTEM FROM RUN TO
RUN WITH ALL OF THE OPERATIONAL GUIDANCE...AND THE PROPENSITY FOR
THE MODELS TO HAVE PROBLEMS NAILING DOWN CYCLOGENESIS...CONFIDENCE
IN THIS CLUSTERING WITH THE NAM/ECMWF IS MARGINALLY LOW THROUGH 48
HOURS AND EVEN LOWER BEYOND F48. DUE TO THE VARYING
SOLUTIONS...HPC IS GOING WITH A CONSERVATIVE SOLUTION BY
RECOMMENDING A TRACK/POSITION CONSISTENT WITH THE BEST CLUSTERING
OF ENSEMBLE GUIDANCE.

[BigB0882]

So, in other words, we have no idea so we will go straight down the middle. lol

[Stormcenter]

SE TX/SW LA. maybe?

So, in other words, we have no idea so we will go straight down the middle. lol

[SouthFloridawx]

Here are the first model runs on 93L

[Aric Dunn]

the bam models are saying a stronger system will likely eventually head off the ene then NE after drifting around for a couple days..

[Jevo]

Here are the first model runs on 93L

https://my.sfwmd.gov/sfwmd/common/image ... orm_93.gif

Awww it looks like a pretty flower

Ive been watching the GFS and Euro pretty intently due to Katia.. They both have 2 different scenarios... which means if I were anywhere in the gulf right now I would keep an eye out.....

[cycloneye]

Key West afternoon discussion:

AREA FORECAST DISCUSSION FOR THE FLORIDA KEYS
NATIONAL WEATHER SERVICE KEY WEST FL
305 PM EDT WED AUG 31 2011

.DISCUSSION...
.CURRENTLY...
KBYX IS UNAVAILABLE DUE TO MAINTENANCE. KAMX DETECTS WIDELY
SEPARATED SHOWERS THROUGHOUT THE FORECAST AREA. SKIES OVER THE
ISLAND CHAIN ARE MOSTLY CLOUDY. WINDS OVER LAND ARE EAST TO
SOUTHEAST NEAR 10 MPH. C-MAN WINDS...ON AVERAGE...ARE EAST TO
SOUTHEAST AT 10 TO 15 KNOTS. TEMPERATURES ARE IN THE UPPER 80S.

.SHORT TERM (TONIGHT THROUGH FRIDAY NIGHT)...
A TROPICAL WAVE NEAR THE YUCATAN PENINSULA WILL PROGRESS TO THE
WEST-NORTHWEST TONIGHT. THIS MAY ALLOW A RATHER WEAK ATLANTIC RIDGE
OF HIGH PRESSURE TO BUILD WESTWARD ACROSS THE FLORIDA PENINSULA
THURSDAY THROUGH FRIDAY NIGHT. PLENTY OF ATMOSPHERIC MOISTURE...WITH
NO CONVECTIVE INHIBITION...SHOULD ALLOW A FEW ROUNDS OF SHOWERS AND
THUNDERSTORMS TO DEVELOP WITHIN MODERATE FLOW OVER VERY WARM WATERS
TONIGHT THROUGH FRIDAY NIGHT.

.LONG TERM (SATURDAY THROUGH WEDNESDAY)...
THE FORECAST FROM SATURDAY INTO THE EARLY PART OF NEXT WEEK IS
HIGHLY UNCERTAIN AS IT HINGES ON WHETHER OR NOT CYCLOGENESIS OCCURS
IN THE CENTRAL OR WESTERN GULF OF MEXICO. THE POSITION AND EXTENT OF
POTENTIAL CYCLOGENESIS ONLY ADDS TO THE UNCERTAINTY. IF CYCLOGENESIS
DOES OCCUR IN THE CENTRAL GULF OF MEXICO...RAIN CHANCES SHOULD BE
HIGHER THAN ADVERTISED SATURDAY THROUGH SUNDAY. NO CHANGES TO THE
LONG TERM PORTION OF THE FORECAST UNTIL FORECAST CERTAINTY INCREASES.

[txwxpirate]

I really hope we get some good rain
and no rain w/name
I want to thank all the awesome pro mets
on this wx site.
I do emergency preparedness for the disability community and often use this site
and other wx sites to help me educate and it keeps me well informed. Thank you.
I'm going back to lurking as this is now an invest and I gotta keep on my toes.

Whatever may come, I hope we are prepared.
Thanks again....

[KWT]

The fact the BAM's are all over the place doesn't do much for the confidence does it!

[Comanche]

Euro does not move this for 4 days so far

its called a Rex Block....

Really like this "Rex" guy, he can drop by my house for a beer anytime he wants.

[KWT]

I'll give it 2-3 days before the thread on 93L/Future Lee passes the thread on Katia in number of pages.......

If it stalls for a few days in the GOM as some models have it may well get close to Irenes one.

Likely will get quite alot of pages, much really depends on the track as you say, if it hangs about and becomes a hurricane, then it may run it close.

[jabman98]

I realize it's way early, but for mental planning purposes, when do most of the models suggest this will develop? I think I'm seeing Friday?

Also, I'm in Houston and a family member is returning from several weeks abroad on Tuesday. This family member is the one who I need to help me prepare the house for a hurricane, should need arise. Should I start lining up other help just in case, or would Tuesday be too early to be be worrying about an imminent hit from a hurricane? I'm well inland and we didn't flood in Allison. I'm not too worried about flooding and storm surge isn't an issue. Wind would be, though.

I know it's way early, but am just trying to think ahead. Thanks for any thoughts.

[gboudx]

Here's Allan Huffman's thoughts. For those not familiar he is a pro-met based in Raleigh, NC.

Gulf of Mexico

The NHC has raised the area in the Gulf of Mexico to a 30% code orange area. The area is not well organized at the moment as it appears some shear is in the area. This will probably be an area that takes some time to develop. Both the 12z GFS and Euro have a 1007mb low in the northwestern Gulf by Friday morning. They both allow the system to sit in the Gulf and intensify although the GFS is further east near southeast Louisiana and the ECMWF is off the La/Texas border by Labor Day morning.

The GFS then absorbs the storm into a trough in the eastern US as Lee would make landfall in the Florida panhandle. However, it is significantly different than the rest of it’s ensemble members which are further west with Lee in the western Gulf of Mexico as the trough to its northeast bypasses it. This lines up also with the new 12z ECMWF. The euro then strengthens Lee into a category 2 hurricane and moves it to the WSW into southern Texas by next Wednesday. Many of the 12z GFS Ensemble members show the same thing and few show what the operational model shows.

The bottom line is that the global models are showing the development of significant tropical cyclone in the Gulf this weekend and over Labor Day. There is still uncertainty with this as it may get picked up by a trough and threaten the central or eastern Gulf next week, or be missed by this trough and threaten the western Gulf. I would say the odds right no favor the latter scenario.

http://www.examiner.com/weather-in-rale ... ts_article

[KWT]

These set-ups are always interesting, I'm fully expecting a wobbly all over the place type path, just the type to get storm2k buzzing!

[djmikey]

Why is wunderground showing Invest 93L as Invest 93. It's from Aug 18th!

Nevermind...they just changed it as I hit send.

[GCANE]

Plenty of time and juice for this to work with

http://cimss.ssec.wisc.edu/tropic/real- ... /main.html

[micktooth]

Any ideas on intensity yet? Do most models predict a TS or Hurricane? I remember living in NOLA for Allison and even though she was near Houston, our house almost flooded. Any slow moving tropical system has the potential to dump a ton of water on the Gulf South.

The above post is NOT an official forecast and should not be used as such. It is just the opinion of the poster and may or may not be backed by sound meteorological data. It is NOT endorsed by any professional institution including storm2k.org For Official Information please refer to the NHC and NWS products.

[Aric Dunn]

18z Nam rolling in.... little farther east

http://mag.ncep.noaa.gov/NCOMAGWEB/appc ... mageSize=M

[Ivanhater]

Experimental GFS/ENKF Ensembles are clustered around the north central Gulf coast

[South Texas Storms]

What is the ENKF model? I've never heard of it before.