Outflow on West Side

[golter]

Does anyone else find it interesting that there is basically no outflow W of 88W? Is this significant?

[mf_dolphin]

It would appear that the shear is limiting the outflow on the west side. The bad thing is that the shear is forecast to subside soon. With the eye already getting better organized if the shear lets up Ivan could reintensify pretty quickly. The 11AM advisory also noted that there is a warm eddy in front of Ivan. That's more bad news....

[PurdueWx80]

It just so happens that the edge of the ridge that is centered over the TX and western LA coast is right around 88W. This basically acts like a wall in regards to Ivan. If we are going to see a ridge build north of Ivan, we will want to look for a flattening of the outflow on the northern side of the storm. That would give better indication of a more western hit. We would need to look for that within 12-24 hours or so.

[Lindaloo]

What about the dry air being pulled into his NW side? Is this having an affect on his west outflow as well?

[PurdueWx80]

The NHC mentioned that some of this dry air is below the outflow canopy, so we can't exactly see it. The drier air is probably helping to diminish clouds in this region, though. I think the outflow we are seeing is between about 300-200 mb, whereas the dry air is closer to 500 mb.

Check out this 500 mb analysis from this morning.
http://www.rap.ucar.edu/weather/upper/upaRAOB_500.gif

There is very dry air from Alabama to SW MO to NW LA. The upper number at each ob is the temperature, and the one below it is the dew point depression. Large dew point depressions mean that there is very dry air. These depressions are much less at 200 and 300 mb.

The outflow at all levels of the storm should be capable of mixing out some dry air, but if it keeps being advected in it will only hinder future development.

[HouTXmetro]

Looks like Ivan is starting to beat back some of that dry air. Not good.

[Lindaloo]

Thanks Purdue!