? About blocking High and Ivan

[HouTXmetro]

If the forecast holds true and Ivan runs into a blocking High near the Gulf, how come Ivan will still move North? Doesn't Highs steer Hurricanes? With that said, shoudn't Ivan move around the High which would actually send it S-SW around the High?

[HouTXmetro]

Somebody please answer? Why Wouldn't Ivan move clockwise around the high? That would give him a Southern movement correct?

[tronbunny]

Bump
Good question.

[Canelaw99]

If I'm not mistaken, I think by then the Coriolis effect will start to take hold, meaning the storm will want to go northward towards the pole....with that being said, as I understand this blocking high, it's like a wall that the storm would run into...so....if it runs into the wall and it wants to be pulled north, it would go northerly around the high, not south around the high....

But, remember, I said as I understand it - I'm not a pro. weather person, just someone trying to learn this stuff through the board also....

[tdess02]

My take on this "blocking High" that is forecast to be over the west Gulf is that with that High to the west and the Atlantic High to the East which is steering Ivan, there will be a weakness between the 2 Highs which would cause Ivan to move North. It is still a question as if that High developes and how strong the Atlantic Ridge holds, but either way it looks like a North Central to East Gulf Coast Target.

[southerngale]

We can all read model maps. It would be nice for an explanation of the reasoning behind certain models by our mets/amateurs, like what causes the models to shift left/right, etc. Some of us aren't very good at reading the weather maps so we don't understand the reasoning behind them.

[skysummit]

My take on this "blocking High" that is forecast to be over the west Gulf is that with that High to the west and the Atlantic High to the East which is steering Ivan, there will be a weakness between the 2 Highs which would cause Ivan to move North. It is still a question as if that High developes and how strong the Atlantic Ridge holds, but either way it looks like a North Central to East Gulf Coast Target.

This is what I have heard also. Frances will leave sort of a trough in its wake and with the High in the western gulf, and the High over the Atlantic, this trough will be sort of a "gateway" for Ivan to pass....toward the Central or Eastern Gulf Coast.

[southerngale]

This was from DT at 11am. At the 2pm update, Ivan was at 11.9 N and 61.2 W

The models divergence past 72 hours is still there so once more It is time to set some new BENCH MARKS for IVAN -- the method that worked so well with CHARLEY and FRANCES. Of course anyone looking at the Vis or IR can see Ivan is going to pass well south of Barbados which is MUCH further south then what the offiical forecast track from SUNDAY and MONDAY morning was calling falling .... and TPC has made that correction...as they usually do..

1st BENCHAMRK WHERE DOES IVAN CROSS 60 LONG TODAY?
IF IVAN crosses up by 12.5N then a track more like the Euro is showing seems likely. But if he crosses by say 11.4 N to say 12.0N then we are looking at a much more western track. In addition the closer IVAN passes to the north side of Trinidad the more likely we are looking at a CBH and a Gulf cane

[southerngale]

Oh yeah, link for above.

http://www.wxrisk.com/

[rtd2]

Quote " 1st BENCHAMRK WHERE DOES IVAN CROSS 60 LONG TODAY?
IF IVAN crosses up by 12.5N then a track more like the Euro is showing seems likely. But if he crosses by say 11.4 N to say 12.0N then we are looking at a much more western track. In addition the closer IVAN passes to the north side of Trinidad the more likely we are looking at a CBH and a Gulf cane"



PER 5PM NHC ADVISORY looks like we got 12.0 and 60.0 seems to split the above benchmark! what now?

[blizzard20]

ecwmf and gfs has the hurricane over or near florida area . Either way the hurricane if its in the eastern gulf will move Northeast across florida to the altantic ocean area .

[southerngale]

Quote " 1st BENCHAMRK WHERE DOES IVAN CROSS 60 LONG TODAY?
IF IVAN crosses up by 12.5N then a track more like the Euro is showing seems likely. But if he crosses by say 11.4 N to say 12.0N then we are looking at a much more western track. In addition the closer IVAN passes to the north side of Trinidad the more likely we are looking at a CBH and a Gulf cane"



PER 5PM NHC ADVISORY looks like we got 12.0 and 60.0 seems to split the above benchmark! what now?

12.0 and 62.0 at 5pm, not 60.0

[vbhoutex]

If the forecast holds true and Ivan runs into a blocking High near the Gulf, how come Ivan will still move North? Doesn't Highs steer Hurricanes? With that said, shoudn't Ivan move around the High which would actually send it S-SW around the High?

The blocking high will have a trough in front of it left behind by Frances. the winds in association with the trough will be from the SW out in front of the trough. That is what would steer Ivan on a more Northerly course. The blocking high would have clockwise winds as stated, but the trough out in front of it has counter clockwise winds and the winds furtherest out in front of the high are the SW or South winds which are anticipated to pick up Ivan. this may be a little simplified, but it is the basics of what we are looking at in relation to the question.