335 replies to this topic

[WeatherNC]

downeastNC, on 27 September 2010 - 07:49 PM, said:

Looks good we will take the TVCN thats perfect hehe.

1001mb ship report (C6FN5) at 0z, lowest I can find and fits nicely with where the NHC initialized the invest...



soupy air too...

[WeatherNC]

NAM spits out a storm off Cape Canaveral 42hrs, sub 1000mb...



Should be an interesting interaction with the ULL



997 into Myrtle Beach six-z Thursday, copious QPF, moving up through central NC into VA, with a strung out tail extending down to the Bahamas, which then forms another GIC off Miami at 66 hrs as the first low is near Winchester VA.

[downeastNC]

Not to much spread overall in the models the real question is what is the thing gonna be pure tropical or mixed up POS. Even a fully tropical storm on the western tracks still should give us a decent hit here but something down the middle and a bit slower like some models have could mean a bonafide solid Cat 1 or dare I hope it over performs and makes it to a weak Cat 2 coming in ILM and hitting us pretty good.

[crossthread]

I'll take it... cat 1... Lotsa fun!

[WeatherNC]

Brings a large chunk of the Caribbean up with it...

[Bozart Farm]

downeastNC, on 27 September 2010 - 10:16 PM, said:

dare I hope it over performs and makes it to a weak Cat 2 coming in ILM and hitting us pretty good.

That would be a lot of intensification, mighty fast, starting from nothing 60 hours out, with land to cross on its way here. I'm just hoping for a final blow to this drought.

[WeatherNC]

For entertainment purposes only.

18z GFDL (976) - big hit



18z HWRF (963) - big miss

[downeastNC]

Bozart Farm, on 27 September 2010 - 11:20 PM, said:

That would be a lot of intensification, mighty fast, starting from nothing 60 hours out, with land to cross on its way here. I'm just hoping for a final blow to this drought.

I dunno depends on the track if its more east then the east side may never see land until ILM, if its a true tropical core and can actually get the pressure down to around 990 then a solid Cat 1 is well within reach and all it would take would be a small burst right before landfall a la Bertha to get more. Honestly I dont expect that at all and think a mid range TS weak Cat 1 is about all we can hope for. Wioth the drought and recent soaking it prolly will not take more than some 50-60 mph gust to knock lots of trees down. We dont need the rain its gonna bring after today lol besides most of it is gonna end up in the rivers anyways.

[RevDodd]

Morning models seem to be converging on landfall north of Charleston and west of Morehead City. GFS at 60 slaps our neck of the woods pretty well. Looks like about 986 or so, so strong TS, maybe minimal Cat 1? And lots, lots of rain.
 gfs60.png (70.11K)
Number of downloads: 5

[WeatherNC]

Quote

000
ABNT20 KNHC 280909
TWOAT
SPECIAL TROPICAL WEATHER OUTLOOK
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
510 AM EDT TUE SEP 28 2010

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

SATELLITE AND SURFACE OBSERVATIONS INDICATE THE LARGE LOW PRESSURE
SYSTEM LOCATED OVER THE NORTHWESTERN CARIBBEAN SEA IS CONTINUING TO
STRENGTHEN AND THUNDERSTORM ACTIVITY IS BECOMING BETTER ORGANIZED.
SURFACE PRESSURES ARE FALLING AND SUSTAINED WINDS HAVE NOW
INCREASED TO NEAR TROPICAL-STORM-FORCE. ENVIRONMENTAL CONDITIONS
ARE BECOMING MORE FAVORABLE FOR DEVELOPMENT...AND ONLY A LITTLE MORE
ORGANIZATION OF THE ASSOCIATED THUNDERSTORM ACTIVITY IS NEEDED FOR
THIS SYSTEM TO BECOME A TROPICAL DEPRESSION OR A TROPICAL STORM
AT ANY TIME. THERE IS A HIGH CHANCE...80 PERCENT... OF THIS SYSTEM
BECOMING A TROPICAL CYCLONE DURING THE NEXT 48 HOURS. INTERESTS IN
CUBA...THE CAYMAN ISLANDS...THE FLORIDA KEYS...AND THE CENTRAL AND
SOUTHERN FLORIDA PENINSULA SHOULD MONITOR THE PROGRESS OF THIS
SYSTEM. FOR ADDITIONAL INFORMATION... CONSULT STATEMENTS FROM YOUR
NATIONAL WEATHER SERVICE FORECAST OFFICE OR NATIONAL METEOROLOGICAL
SERVICE.

$$
FORECASTER STEWART

I would say something between the AEM and AVN, Myrtle Beach - Topsail area, likely in between around ILM...



Note, that cluster that keeps it well offshore is made up of mostly the statistical-simple models. The landfalling group are the more advanced dynamic ones...

[RevDodd]

MHC discussion makes it look like a nasty day for y'all...

"THURSDAY NIGHT CONTINUES TO BE THE PERIOD OF CONCERN AS THE NEXT SHORTWAVE AND
UPPER LOW DIG THE BASE OF THE UPPER TROUGH FURTHER SOUTH. THE
STALLED FRONT IS LIKELY TO BE THE FOCUS FOR THE ENERGY FROM THE
TROPICS WITH ONE OR MORE LOWS TRACKING ALONG IT WED NIGHT-FRI.
CURRENTLY LOOKS LIKE THESE LOWS WILL BE EXTRA- TROPICAL BUT THEY
COULD PRODUCE A PERIOD OF GALE FORCE WINDS AND VERY HEAVY RAINS.
THERE IS STILL MUCH UNCERTAINTY ON THE TIMING/TRACK/INTENSITY OF
THIS SYSTEM. HPC QPF CONTINUES TO SHOW RAINFALL AMOUNTS OF 4-7
INCHES WITH THIS SYSTEM. COUPLED WITH THE HEAVY RAINFALL FROM
MONDAY...THE THREAT FOR SIGNIFICANT FLOODING WILL BE A CONCERN
WEDNESDAY-FRIDAY WITH THE POSSIBILITY OF COASTAL FLOOD ISSUES IF
STRONG WINDS MATERIALIZE."

Wilmington seems less impressed:

STILL A LOT OF UNCERTAINTY CONCERNING THE TIMING
AND STRENGTH OF THIS FEATURE...WHICH MAY OR MAY NOT BE OF TROPICAL
NATURE BY THE TIME IT REACHES THE CAROLINAS. WHAT DOES SEEM LIKE A
GOOD BET IS ANOTHER ROUND OF HEAVY PROLONGED PRECIP ON WED. DEEP
TROPICAL MOISTURE REMAINS IN THE AREA ALONG WITH LOW LEVEL
CONVERGENCE AND GOOD DIVERGENCE ALOFT. ON WED BIGGEST QUESTION MAY
END UP BEING HOW MUCH PRECIP WILL FALL. HIGHEST PRECIP SHOULD BE AT
THE COAST...FORECAST SOUNDINGS KEEP PRECIPITABLE WATER VALUES OVER 2
INCHES WED AND WED NIGHT TOPPING OUT AT 2.74 INCHES THU MORNING.
FOUS PRECIP TOTALS FOR WED AND WED NIGHT APPROACH 4 INCHES AT ILM.

[RevDodd]

WeatherNC, on 28 September 2010 - 06:53 AM, said:

Note, that cluster that keeps it well offshore is made up of mostly the statistical-simple models. The landfalling group are the more advanced dynamic ones...

Dynamic? Not sure I follow. I'm guessing that means they're looking at other variables than simply where the storm track "should" go. IIRC, the boundary was projected to develop a negative or at least neural tilt, which is why the system is heading this way in the first place.

Do the other models simply not factor that in?

[downeastNC]

RevDodd, on 28 September 2010 - 06:21 AM, said:

Morning models seem to be converging on landfall north of Charleston and west of Morehead City. GFS at 60 slaps our neck of the woods pretty well. Looks like about 986 or so, so strong TS, maybe minimal Cat 1? And lots, lots of rain.
gfs60.png

986 is a solid Cat 1 in most cases (however it can vary quite a bit remember Earl was a 950mb TS ) low 990's equal 70-75knt storm. The GFDL and HWRF are taking it to 970ish off of Florida that would be a Bertha type 100-110 mph and then it really gets interesting. My thing is timing seems like this would have to slow down some and be more a Friday into Sat thing not a Thursday into Friday hit.

The GFS map WeatherNC posted has all of this area in 65-75 knt winds so a solid Cat 1 event along and east of I-95 really this would be the best case scenario for this setup so we will just have to wait and see if it forms ( looks good) and how the NHC plays it out.

[Wow]

If the ULL bottoms out a bit more SW and a neg tilt per the 6z NAM, the better the chance for more western areas to get in on it with a more NNW trajectory of the system rather than due N.

[downeastNC]

What really sucks is I am working nights first half of this week so I just got home and gotta sleep so I can work 7-7 tonight so I will miss all the fun of watching Nicole get born, I will know good things happened if this thread is 10 pages longer when I wake up around 4-5 this afternoon........

Look at her go this will be a TD or straight to Nicole by 11 am

http://www.ssd.noaa....2/flash-ft.html

[downeastNC]

Wow, on 28 September 2010 - 07:18 AM, said:

If the ULL bottoms out a bit more SW and a neg tilt per the 6z NAM, the better the chance for more western areas to get in on it with a more NNW trajectory of the system rather than due N.

Also the ULL could help setup a period of strengthing for the TC by venting it, then maybe we do get a decent wind event to go along with the rain we dont need that close on the heels of the 6" we got yesterday.

[WeatherNC]

RevDodd, on 28 September 2010 - 07:11 AM, said:

Dynamic? Not sure I follow. I'm guessing that means they're looking at other variables than simply where the storm track "should" go. IIRC, the boundary was projected to develop a negative or at least neural tilt, which is why the system is heading this way in the first place.

Do the other models simply not factor that in?

Hope this helps...

http://www.tropicala...cgi?page=models

http://www.nhc.noaa....n/verify6.shtml

Allan's model page breaks them down, statistical and dynamic, and the links above give detailed information about what each one is.

Also, that GFS map was 900mb winds, surface map keeps all the TS force winds on or off the coast.

6z earl cycle intensity forecast, starting to see a nice group between the 50-60 kt range at 48 hrs...

[RevDodd]

WeatherNC, on 28 September 2010 - 07:46 AM, said:

Hope this helps...

http://www.tropicala...cgi?page=models

http://www.nhc.noaa....n/verify6.shtml

Allan's model page breaks them down, statistical and dynamic, and the links above give detailed information about what each one is.

Also, that GFS map was 900mb winds, surface map keeps all the TS force winds on or off the coast.

'Preciate it!

[eyewall]

I have a feeling this might be a covoluted mess but obviously if it ends up a cane at ILM I will be there. There is unfortunately a good bit of model divergence in the track forecast.

[Lookout]

Wow, on 28 September 2010 - 07:18 AM, said:

If the ULL bottoms out a bit more SW and a neg tilt per the 6z NAM, the better the chance for more western areas to get in on it with a more NNW trajectory of the system rather than due N.

That's what I'm hoping. I was surprised a little bit by how much further southwest the 06z nam had that upper low. 12z nam is just a touch further north but it's noise level. It's going to be a razor thin margin here as far as the rain goes. 30 miles could mean the difference between no rain and a couple of inches I think since there is going to be a pronounced dry slot on the eastern edge of that upper low. I really didn't think there was much chance here of anything significant but the nam runs, and even the gfs, clearly indicates there is a chance at least now. Meanwhile, of course this puts all of south carolina in the running for heavy rain and most of nc, except maybe the extreme southwest mountains.

You can see here how sharp the western edge will be. Going to be a nail biter here.



btw, the nam has a strong easterly upslope flow into the mountains for quite a while. Edit, 850mb winds of 50knots to 70 knots or so touching the eastern mountains and in the foothills. So some heavy rainfall for sure there is a possibility and the 12z nam agrees.



This is just sick.



A ridiculous sharp cutoff as I was talking about. If this was 100% accurate, I'd be a little sick.