05/18/06 FCST: NY / PA / NJ / VA / WV / NC / KY / OH

Some marginal chances for severe weather here in the Mid-Atlantic states today. Prog of decent surface heating seems to be emerging, via satellite obs and direct obs here in Richmond. Interesting, much of the morning cu is appearing to take on a lenticular shape....not sure if this is a matter of CIN vs. some mid-level shear or waves from last night's convection over OH valley that isn't readily apparent. No doubt that some strong deep layer shear is moving our way, w/ td's and surface-based CAPE slowly but steadily on the increase, and low-level lapse rates of 8.5 may be come even steeper this afternoon.

The obvious negative condition is the lack of prospect for backing surface winds today. As a matter of fact, the whole of the flow seems to be very uni-directional. I'm still hopefull the approaching surface boundary, which is fairly vigorous, will spur enough convergence underneath an obvious upper-level diffluent condition such as to initiate a few supercells in the area. Surface low in northern Great Lakes continues to dominate the lower level winds, so some hope for any surface backing around here is just that - a hope. At any rate, will keep eyes and ears open today for any prospect of a chase.
 
As a follow-up, after going outside to observe to the cloud patterns, I'm more convinced it is - as usual - a lack of instability, rather than strong shear, which is cutting down the cu. Low LCL's are great, many mornings we can see condensation in the air literally on top of our little toe. However, true working LFC's are few and far between in this area of the country. The cu now appears very tilted from SW to NE, but it reflects the influence of the overall flow rather than any influence of deep shear - as of now at least.

Still remain hopefull. After all - ANY surface winds of 18 gust to 24 are rare in this part of the country, and it is still early in the day....not much velocity or tilting apparent from the radar echoes out of Blacksburg so far....just still hopefull perhaps some kind of mesolow will form leeward of the Appalachians this afternoon. Any insights on this setup would be appreciated. Thanks.
 
Any insights on this setup would be appreciated. Thanks.
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I am not impressed with the setup across the Northeast today (Eastern NY/Western MA). Low level lapse rates are very steep, dew points are in the low 50's and CAPE is 500-1000 J/Kg, but the other paramters that are needed for severe are lacking. Instead of mentioning each and every one, I'll just say that I expect showers and t-storms to be likely but only a few isolated storms will pulse severe with a hail/wind report or two at best. I'm not planning on chasing at all today since I expect the storms to be moderate at best. If I see some decent lightning or perhaps some pea sized hail like yesterday, I would be happy.
 
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