6/16/07 FCST: SD/ND/MN/MT

[Dave Winslow]

Wanted to start a new thread for our northern plains chasers for Saturday. Fairly respectable ridge building into the region will keep wind fields rather meager but westerly flow from about 25-30 kts at 500 MB and ESE sfc flow around stationary front in central South Dakota yields decent turning and supercell possibilities.

These areas (eastern half of SD) have been inundated with rains for a good part of the spring and have consistently been showing higher dewpoints than surrounding areas. This should offset somewhat marginal return flow from Gulf of Mexico with cut-off upper low over Oklohama and southern plains disrupting best moisture.

GFS most bullish in painting QPF with a weak cap, 700 mb temps AOB 10 C in central SD.

My target is central South Dakota, or points NW of Huron.

 

[Mike Hollingshead]

I'm liking this day as well. The forecast soundings from this afternoon's 18z nam run are too tempting to not chase this. I'm hoping a storm can fire somewhere between Pierre and Rapid City.

RAP

PIR

 

[Jayson Prentice]

I'll be out there as well for tomorrow and Sunday with other ISU students and others... The NAM and even GFS have both shown nice potential along the warm front in SD during the evening. Good shear values as shown by those skew-t's, with instability and capping both being sufficient for supercells, possibly some isolated. With surface winds nearly eastward, then turning quickly back to the west with height it has very good low-level rotation possibilities. A great day in the northern plains in June...

 

[Michael O'Keeffe]

I like tomorrow as well. I will probably be heading out too and our target is somewhere between Rapid City to Pierre over to Huron. Cape is to be around 4000j/kg and helicity is excellent. Hopefully we can have an OFB interact with the WF. We also will have no capping issues as well. Tds should be good, but could be better although with all of the rain we've been getting we could have so ecoevaportation. I will make the final call in the morning.

 

[Billy Griffin]

Currently on data stop in Spokane. Will continue the drive east onto the high country of MT today. Not too bad of a drive over here from Seattle - very little traffic.

Upslope should aid in the development of storms in this area, and this is my first time chasing in Montana. TDs aren't even too bad even here in eastern WA, but I expect the best action will be east of the mountains later today. I hope to get to Shelby, MT by 3pm MDT.