Saturday, June 18, 2011

Active Weather to Continue This Weekend...

The above image is the latest severe weather outlook for Saturday from the SPC in Norman, OK.  Severe thunderstorms are possible within the whale shaped area shaded in yellow (sorry, couldn't resist the description...)

While the severe weather outlook area is rather broad in coverage, there are a few areas with higher potential for specific types of severe weather this afternoon & evening.  First, lets take a look at potential wind damage:

The areas with the highest risk of damaging thunderstorm winds are within the red shaded regions on the image above.  A risk of "significant" wind damage lies within the black hatched region on the same image.  This would include the Wichita, Emporia, Salina, Topeka, Kansas City Metro, Springfield, Joplin, Columbia and St. Louis areas.  

An enhanced risk of very large hail is likely with severe thunderstorms that form within the red shaded & black hatched area on the image below:

As you can see by combining the highest damaging wind & hail probability maps above, the greatest concentration of severe thunderstorm activity, potentially significant, will be over central and Eastern Kansas into much of Missouri today.  While large hail & damaging winds will be the primary severe weather threat, isolated tornadoes also cannot be ruled out, particularly as thunderstorms initially develop and are more isolated to scattered in nature.  

Two large complexes of thunderstorms, which formed from activity that initially developed yesterday evening and overnight, are currently advancing Southeast across the Tennessee Valley and into the Deep South:

Severe thunderstorms may re-organize and/or re-develop along and ahead of this activity later this morning and into this afternoon.  Damaging winds and hail would be the primary severe weather threats from this activity across the Deep South.  I would expect the severe weather outlook area in image 1 to be extended further South and East along and ahead of this activity on the late morning update from the SPC.

Otherwise, thunderstorms are expected to develop by late afternoon across the primary severe weather threat area of Kansas and Missouri.  There are numerous boundaries in the region left by thunderstorm activity of yesterday, as well as an upper level weather disturbance that will add additional focus for development this afternoon & evening.  This activity will move and/or develop Eastward and Southeastward over time, and is also likely to form into a larger complex of thunderstorms by tonight, which will traverse across the remainder of the severe weather outlook area.

Large hail, damaging winds and isolated tornadoes will be possible with this activity as it initially forms late this afternoon into this evening.  By late evening and into tonight, damaging winds will become the primary threat as the activity congeals into a larger system.

If you live anywhere within the severe weather risk area on image 1 (and within the red shaded / black hatched areas on images 2 and 3 in particular), please keep a very close eye on the weather this afternoon & evening.  Listen to NOAA Weather Radio or other severe weather sources for your area and be prepared to seek shelter immediately if threatening weather approaches.

Active weather is expected again on Father's Day, with severe storms currently forecast within much of the same general area as today:

At this time, it appears that severe storms on Sunday may be particularly focused within the red shaded and black hatched areas on the image below.  This could of course change as boundaries are laid out by thunderstorm activity today, which could affect development on Sunday:

No comments: