Thursday, April 12, 2012

Severe potential this weekend

A potentially explosive severe weather situation is setting up over the Central Plains this weekend as a low pressure area, with associated warm front and dry line, set up east of the Rockies on Saturday.

sfcmap_04152012_00z

A moist, unstable air mass is forecasted behind the warm front and out ahead of the dry line.

Strong south winds at the surface turning more westerly with height will help create enough shear in the atmosphere for rotating supercells.  These supercells will be capable of producing tornadoes, perhaps large and destructive ones.  In addition, large hail and damaging winds can be expected.

Winds at 850 millibars (~5,000 feet):

NAM_221_2012041300_F42_WSPD_850_MB

Winds at 500 millibars (~18,000 feet):

NAM_221_2012041300_F42_WSPD_500_MB

The area where I see the greatest threat for severe thunderstorms, including tornadoes, is over eastern Nebraska and western Iowa.  If I wasn’t going to a Twins game Saturday at Target Field, I would consider the Sioux City, Iowa area as an initial chase target.

NAM_221_2012041218_F48_EHI_3000_M

As for Minnesota, it will all depend on where the warm front lines up.  If the models move it further north over the next day, then the chance for severe thunderstorms increases in the area.  Right now, the bulk of the heaviest weather should stay south of the Interstate 90 corridor.  Any strong storms that develop north of the warm front in an elevated environment will be capable of hail and gusty winds.

RS

No comments:

Post a Comment