ATL: KARL - Ex-Hurricane - Discussion

[Bailey1777]

seems to me that the further north it gets pulled early on the more risk it poses on the gulf states as it gets blocked back westward.

[cycloneye]

Remains at 40%

TROPICAL WEATHER OUTLOOK
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
200 PM EDT THU SEP 9 2010

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

THE NATIONAL HURRICANE CENTER IS ISSUING ADVISORIES ON TROPICAL
STORM IGOR...LOCATED ABOUT 65 MILES NORTHWEST OF BRAVA IN THE CAPE
VERDE ISLANDS.

SHOWERS AND THUNDERSTORMS ASSOCIATED WITH A WEAK AREA OF LOW
PRESSURE LOCATED NEAR THE WINDWARD ISLANDS HAVE CHANGED LITTLE
DURING THE LAST SEVERAL HOURS. THIS SYSTEM CONTINUES TO SHOW SIGNS
OF ORGANIZATION...AND ENVIRONMENTAL CONDITIONS APPEAR FAVORABLE FOR
SOME GRADUAL DEVELOPMENT AS THE LOW MOVES SLOWLY WESTWARD. THERE IS
A MEDIUM CHANCE...40 PERCENT...OF THIS SYSTEM BECOMING A TROPICAL
CYCLONE DURING THE NEXT 48 HOURS.

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

$$
FORECASTER CANGIALOSI/BRENNAN

[Bailey1777]

can someone explain why there is such a discrepancy in the models?

[RL3AO]

can someone explain why there is such a discrepancy in the models?

Really weak steering currents so the models don't know what to do.

[chrisjslucia]

can someone explain why there is such a discrepancy in the models?

Not me, but there seems to be a certain consistency showing Jamaica as dead centre of the track and the first major landfall after the Windwards. As it is heading west, it has not impacted the north of St Lucia - I had guessed we were in for heavy rain earlier today but it has kept south of here and we're just on the fringe, with overcast conditions. Still raining in Grenada I'm told.

Of concern is what impact this might have on Igor, as mention has been made of 92L pulling Igor more westerly. Or is that dependent on the track 92 takes?

[Vortex]

GFDL/HWRF/NAM/Nogaps/CMC all lift 92 N/NW towards PR into the weakness as the polar trough passes to the N with a bend back towards the w/wnw....this seams reasonable given the forecasted synoptics....

[tolakram]

can someone explain why there is such a discrepancy in the models?

No center, no accurate point to initialize on.

[HURAKAN]

Latest

[Bailey1777]

even without a center wouldn't the laws of synoptics come into play. imaginary center still playing off the real time synoptics as they are forecast to occur?

[tolakram]

even without a center wouldn't the laws of synoptics come into play. imaginary center still playing off the real time synoptics as they are forecast to occur?

Yes, which is why one might guess this will move NW (just because due north is rather insane). It's easy for a human to evaluate the problem and apply some reasoning to it, computer programs can only do what they're programmed to do and when a condition isn't handled the results are usually wrong.

[KWT]

GFDL/HWRF/NAM/Nogaps/CMC all lift 92 N/NW towards PR into the weakness as the polar trough passes to the N with a bend back towards the w/wnw....this seams reasonable given the forecasted synoptics....

I have a funny feeling they are overdoing it, quite a few of those models are knowing to be a little overzealous on weakening the upper flow...the 12z ECM looks about right...IMO upto 15-17N then a bend to the WNW...certainly could be enough to threaten some of the islands.

That being said it IMO will gain enough latitude to at least be a threat to possibly Hispaniola and Cuba and as you say the bend back west solution is probably a good one given the upper ridging that builds over the SE states.

Without a doubt this one will probably be the story of the season along with Alex, Earl and maybe another October system.

[Sambucol]

About many days away would 92L enter the GOM, if it does at all? Thanks.

[hurricaneCW]

GFDL/HWRF/NAM/Nogaps/CMC all lift 92 N/NW towards PR into the weakness as the polar trough passes to the N with a bend back towards the w/wnw....this seams reasonable given the forecasted synoptics....

I have a funny feeling they are overdoing it, quite a few of those models are knowing to be a little overzealous on weakening the upper flow...the 12z ECM looks about right...IMO upto 15-17N then a bend to the WNW...certainly could be enough to threaten some of the islands.

That being said it IMO will gain enough latitude to at least be a threat to possibly Hispaniola and Cuba and as you say the bend back west solution is probably a good one given the upper ridging that builds over the SE states.

Without a doubt this one will probably be the story of the season along with Alex, Earl and maybe another October system.

Well who knows, it might not even get its act together. I had a feeling that Julia or Juliette would be one of the big ones this season, I never was feeling the name Igor like most on here were.

[South Texas Storms]

does anyone else think that this could have a track similar to hurricane allen in 1980?

[jlauderdal]

can someone explain why there is such a discrepancy in the models?

weak flow, weak system

[cycloneye]

18z Best Track

AL, 92, 2010090918, , BEST, 0, 123N, 610W, 20, 1009, DB

ftp://ftp.tpc.ncep.noaa.gov/atcf/tcweb/ ... 010.invest

[frederic79]

With the troughiness the Atlantic has shown for some time now around 60W, you'd have to think that anything that could threaten the Gulf states would have to develop west of there. This may be that storm, if it develops. This season, development is hit or miss.

[Wthrman13]

even without a center wouldn't the laws of synoptics come into play. imaginary center still playing off the real time synoptics as they are forecast to occur?

It's not really the "laws of synoptics": it's the laws of fluid dynamics as applied to the atmosphere (and coupling with the ocean, land surface, etc, etc.), but yes, your intuition is correct. Given a good set of initial conditions and a good numerical model that faithfully represents all the relevant physical processes, you don't need a "center" to initialize a storm and still get a good forecast. That is, a good model (with good initial conditions) should be able to develop a storm in situ based on the laws of physics. That said, many models contain optional "bogussing" routines that artificially place an idealized TC vortex into the initial condtions to help the model along a little, because most of the models (particularly the global ones) don't have the resolution to adequately resolve small and weak systems, and, more importantly, the initial conditions don't have enough data in them to adequately initialize the storm at the level of detail needed.

[Ivanhater]

The potential is absolutely sickening

[shell70]

Please, a PLEA about the island radars... and please don't flame me, it's only because I care about the people actually IN the bad weather!

Bandwidth here in the islands isn't the same as the states. I'm pretty sure the French and Dutch radars can't handle the load of great interest by the mainland U.S., because I've seen them crumble under load during other storms of interest to US mainland (translation: being hyped on US tv).

For us on the islands, the 3 radars are much more critical than any one radar is in the U.S., there is so little timely data locally. If they get overloaded and crash, nobody can use them.

Just asking users to exert some restraint, and don't be hitting refresh constantly. {off soapbox}

Is there anyway to make this a thread and sticky it because this is important? I didn't realize this information and I imagine there are many of us in the US that didn't know.