Saturday, August 6, 2011

August 6 Severe Weather Discussion

Discussion... Slight Risk of severe weather over North Plains into the Central Plains, with lesser threat in Ohio Valley into Oklahoma region.
Wind shearing in Slight Risk area will not be impressive, with jet stream putting out 50 kts at max. However, this can be enough for a 'weak' tornado to form, thus the low but still present tornado threat. The main threats will be damaging winds and hail. Before we get into that, look at how the slight risk area is laid out. When you see that type of shape in a slight risk area, that is a good sign that A) A squall line will form, or B) There is a cold front. In this scenario, there is indeed a cold front, and it appears that option B is what we will go with. The SPC mentions 'organized strong storms', which would indicate a squall line, or a cluster of storms out ahead of the cold front. At this time, it looks like the GFS favors a storm cluster in the northern severe risk area, with a squall line forming in southern portions. Sketchy CAPE forecast indicates levels will struggle to reach 2000 j/kg in northern regions, but surpass 3000 j/kg in southern sections. Some shearing in the atmosphere could lead to stronger and more intense storms.