Interesting situation

[Derek Ortt]

while the sats and pressure suggests rapid intensification, the wind speeds are 15% lower and do not justify anything more than 110KT, prehaps even as low as 105KT. This will be a serious delimma at the 11 p.m. forecast as to whether or not to upgrade, downgrade, or keep steady

[Mello1]

Question: so this is due to the lag effect right? with the dilemma being the wind speeds may not catch up before it hits Jamaica?

[lilbump3000]

This shouldnt be no delimma, i mean look at the latest infrared. That tells it all. I really want to see what they going to do at 8.

[greeng13]

questions...could the mountains be affecting the outer bands enough to not allow for wind intensification vs. pressure drop? they (the bands) are related to outflow/ventilation correct? or is wind intensification (as mentioned on another thread) to follow shortly?

[Derek Ortt]

I dont care what any satellite image says. If the data shows a clear 3, some consideration <b>MUST</b> be given to indicate a category three hurricane and not a destructive 4 or higher. I am hoping that there is one more pass through the eye before the plane leaves, to settle this once and for all

[Derek Ortt]

we may be seeing the lag from the weakening, plus a lowering of the ambient pressure is another possibility, which decreases the gradient wind

[Indystorm]

Derek, I appreciate your forecasts and am not being sarcastic. But I expect TPC to FOREcast. If data indicate that the pressure is down to 927 mb, but the winds have a lag and have not yet responded to the decrease in pressure, wouldn't they be expected to? Given that the satellite imagery looks very impressive and hard data indicate the pressure falling rapidly, wouldn't they up the intensity to err on the side of caution. I imagine there is an established procedure or precedence as to which parameter takes greater weight in recon.

[Derek Ortt]

the forecast should be for a 135KT hurricane in Jamaica in 6-8 hours, which is likely to occur. However, at the 8 p.m. update, a downgrade to a cat 3 is justified.

What I am afraid of is a Glorida type scenario where the widns are said to be 140 m.p.h., when they are really 90 m.p.h.

[Thunder44]

If Stewart is writing the advisory, Ivan will NOT be downgraded. That's all I have to say.

[huricanwatcher]

gotta wonder if the radars and stuff have been taken over by a third word country...... UGH terrorists!!!

[Coldfront]

Derek,

Is there any possibility that the device measuring the data could be malfunctioning?

The way Ivan looks now, plus the pressure drop, just doesn't seem to add up to a decrease in speed. Something's not right...

Thanks in advance!

[Air Force Met]

Sorry Derek...but a downgrade to a 3...with a pressure of 927...would be a dumb move. ...especially if you are forecasting it to go back up to 135 in 6 hours. No met would ever do that....and the NHC would be negligent if they did.

We also don't know what the drops are finding nearer the sfc. There is no way a <927 storm is only putting out 105-110 kts. Especially one that is deepening at 3.4 mb/hour.

[Derek Ortt]

make no mistake that this will be a near cat 5 at landfall.

I also would not downgrade and am keeping the winds at 145 in the 8 p.m. update. I'll let the downgrading be done by best track since its this close to land. If it were an open ocean storm, I'd likely do things much differently though

[calidoug]

So.. you just completely changed your mind, then ???

O-kay.

[Derek Ortt]

I have not changed my mind.

I am not going to reduce the winds at this point due to non-science reasons. Thousands of people who know nothing at all about storm2k do read these products; thus, I am reaching the general public. I do have to be a bit more careful as to what I may put on nwhhc than what I say here. I still have not seen any data to suggest that Ivan has category four winds... yet