10/26/2010 FCST: IN/MI/OH/IL/KY/TN/MS/AL/GA/PN

[jshields]

i'd be really worried if i was from near indianapolis and south of there into southern indiana. the models have been showing this as a peak of instability with dewpoints forecast to rise into the mid 60's. obviously we know the insane amounts of shear and especially 0-1km shear. the wrf forecast radar seemed to show a peak in intensity here and the line a little more broken than earlier in the day. the spc has gone with a high risk in this area now too, with a 15% hatched area for tornadoes and 60% hatched wind probs. could be a very dangerous situation, especially if it moves through the indianapolis metro area, and forecast storm motions over 60 kts

 

[rdale]

A few points north of St Cloud MN coming in at 967mb, which ties it with the 1940/1998 storms as third lowest.

 

[John Vandehei]

Longville, MN (KXVG) has been reporting 965 mb for the past two hours.

 

[Paul Racine]

961.4 now at Duluth.

 

[John Vandehei]

Eveleth, MN reported 959 mb last hour. The low appears to still be deepening somewhat. Looks like the models did a good job forecasting the strength of the main low. The overnight runs of GFS and NAM I saw were indicating just under 960 mb by mid-afternoon.

 

[Tim Shriver]

We have a new record here in WI.

Old record - Greenbay WI - 963.43 MB April 3rd 1982

New Record - Superior WI - 961.06 MB at 11:35 today

How low can it go.

Tim

 

[Robert Dewey]

Incredible. SFC analysis shows the low down to about 957mb, with the RUC continuing to deepen the system down to about 953mb. This doesn't look too unreasonable to me.

However, warning criteria winds have really failed to develop behind the cold front across IL/IN/MI. There's still opportunity tomorrow for much of the Great Lakes to experience extremely strong winds as low level lapse rates become nearly dry adiabatic up to about 750mb tomorrow (Wed). Within that layer, winds are forecast to be 60-80knts across much of the area... so we'll see what happens.

 

[Robert Dewey]

I know a lot of people are letting their guard down around here, but I think the worst of the winds is yet to come. 0z NAM BUFKIT showing phenomenal mixing layer heights tomorrow afternoon with nearly dry adiabatic lapse rates right up through 700-600mb. It has been insistent on 65-75knts within the mixing layer for the past couple days worth of model runs. In fact, there's a brief spike to 83knts around 19z. It will be interesting to see what the GFS shows, but the NAM solution would offer at least several hours of high wind warning criteria wind gusts of 60-65mph, at least north of a DTW to MKX line. In addition, a strengthening high pressure over the SW US should keep the pressure gradient rather tight, even as the low begins to fill.