Sunday, June 26, 2011

Severe Weather Outlook for Today, Sunday, June 26, 2011

Above is the latest severe weather outlook for today from the SPC in Norman, OK.  Severe storms are possible later today and/or tonight in a broad swath extending from the northern High Plains, Southeastward into the Mississippi and Tennessee Valleys.  Severe storms are possible anywhere within the yellow shaded areas on the image above.  An enhanced risk of severe thunderstorms, including one or more possibly strong tornadoes, is forecast within the red shaded areas on the same image.

A couple of clusters and/or complexes of strong thunderstorms continue to advance East/Southeast across portions of the Mississippi and Tennessee Valleys this morning, as indicated on the radar mosaic image below:

This activity will continue to slowly weaken as it progresses Southeastward this morning.  Gusty winds and some marginally severe hail are possible with a few of the stronger storms.  This activity will likely leave behind several surface boundaries that may focus severe thunderstorm development again late this afternoon or this evening, especially immediately along and to the Southeast of the locations where this present activity diminishes later this morning.

Elsewhere... thunderstorms are forecast to develop rather rapidly by mid to late afternoon across portions of the northern & central High Plains.  In particular, the area from central and eastern Nebraska into western Iowa appears to favor organized thunderstorm development by mid to late afternoon.  The combination of a strong upper-level weather disturbance and a warm front focusing lift and instability at the surface will result in many of these storms becoming severe.  Very large hail, damaging winds and tornadoes will all be possible with this activity.  One or two of the most organized storms may also produce a strong tornado in this region.  The area with the highest risk of significant tornado development lies within the red and black hatched area on the image below:

Once formed, this activity will move and/or develop generally toward the Southeast, with portions of extreme northeast Kansas and northwest Missouri potentially seeing some of this activity move in from the Northwest by this evening.

Very large hail (i.e., greater than 2 inches in diameter), is forecast with severe storms that form within the red & black hatched areas on the image below:

and the threat for damaging winds is highest within the red shaded areas on the following image:

Thunderstorm activity that forms in the northern and central Plains this afternoon & evening is likely to organize into one or more complexes of thunderstorms that will move Southeastward into portions of the Midwest, Tennessee and Mississippi Valleys overnight.  Damaging winds would be the greatest severe weather threat in association with the activity by that time.

There is also a chance for isolated severe thunderstorm development along a dryline extending from southwest or southcentral Kansas into portions of western Oklahoma and extreme northwest Texas late this afternoon or this evening.  A strong capping inversion is in place across this region, which will generally prohibit thunderstorm development today.  However any isolated thunderstorm that is able to form during the peak heating hours of the day would become severe rapidly, with large hail, damaging winds and an isolated tornado possible.

If you live in or near any of the above described areas, please remain alert this afternoon & evening and be prepared to seek shelter if threatening weather approaches your area.

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