Storm Chase Opportunities Monday-Thursday March 8-11

Meteorologist Ted Keller posted this in Forecast Discussion, Storm Chase Discussion on March 7th, 2010

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An interesting set of storm chase possibilities exists over the next few days as a general trough of low pressure develops out west with several wind maximums rotating through it. All model references are to today’s 12 run.

The first is Monday as the first punch of stronger jet stream winds work their way out into the Great Plains. While the best bulk shear will be west of the maximum instability axis, there does appear to be support for some storms along the dry line from western Oklahoma curving northwest into SW Kansas. This was the chase of choice for me for many days, especially when the models were showing it more to the east, but the distance as well as the strength/alignment of the various parameters makes me want to abandon this chase for now.

This same shortwave lifts northeast on Tuesday. A weak surface low follows this feature into eastern Kansas and on this point, both models agree. There is a cold core signal on this day northeast of the surface low which would include Kansas eastward into central Missouri which would include the northern and western portion of the KOLR/KFSX viewing area. Of course, the best instability axis would be in the ArkLaTex area southward into eastern Texas.

A second area of maximum winds comes around on Wednesday. There are differences between the NAM and the GFS with regard to the placement of the surface low by 6 pm Wednesday with the NAM more to the west in eastern Oklahoma. This can be traced to differences in the placement of the upper level jet max. This day will need to watched in the Ozarks and points eastward. The GFS develops an instability axis over southern Illinois while the NAM keeps it over the Ozarks.

NAM Surface/Lifted Index 6 pm Wednesday.

GFS Surface/Lifted Index 6 pm Wednesday.

Ultimately, one cannot ignore the climatological significance of the alignment and strength of the upper level jet Thursday and Friday over the southern and eastern U.S. with progged 90 knot winds at 500 mb and 160 knots at 250 mb Thursday at 6 pm over the Texas and Louisiana. The air would be unstable enough as forecast ahead of the surface front and curling northeast of the surface low into the Tennessee and Ohio river valleys to produce severe weather.