Jump to content
  • Member Statistics

    17,588
    Total Members
    7,904
    Most Online
    LopezElliana
    Newest Member
    LopezElliana
    Joined

July 26, 2012 Severe Weather Potential


earthlight

Recommended Posts

  • Replies 1.1k
  • Created
  • Last Reply

Oh gosh - putting me on the spot! :P I would say as a rough guess that things start popping around 3PM and quickly merge into bowing segments that last through the rest of the evening (and contain the worst of the wind) - even a 5% is still a very 'isolated' tornado risk.

This MCS did exactly what we needed it to. Not only did it moisten the boundary layer to lower LCL heights but it will help slow the northern progression of the warm front and contribute to frontogenesis along it, hence the tornado risk area being shifted further south. Now we wait (and try to get work done and probably fail at it).

Good post. However, climatalogy dictates that we have about a 0.5% chance of tornadoes during each summer day. Having a 5% tornado risk today means that a tornado is 10 times higher than normal. So that is significant.

Link to comment
Share on other sites

likely from NE PA into N NJ, SE NY, and the NYC Area.

...and CNJ ;)

The parameters look very favorable for the metro area, agreed. Bulk shear remains > 30-35 kts through this evening intersecting 2500-3000 J/KG CAPE values.

Still think highest tor risk is NE PA/S NY/W CT. I believe we'll see some intense discrete cells firing around 21z, to our NW, eventually congealing into a larger line of convection which will probably bow out and become a damaging wind event, propagating to the SE with time. My guess is some of the embedded cells in the northern part of the developing complex could be tornadic, in NE PA, maybe NNJ and southern Hudson Valley.

110yfkm.jpg

kbc3mc.jpg

Link to comment
Share on other sites

I agree with Earthlight and Isotherm about the nature of the thunderstorms this evening and how it may go down in evolution. A significant wind damage event seems probable in our area this evening. The initial supercells this afternoon that form in N PA / C PA may struggle with tornadogenesis for you chasers out there. Anything tornadic this evening will not be chaseable not only for the location/timing but with their nature (fast / embedded in a line).

Link to comment
Share on other sites

Tom, I agree with most of your thoughts. But I think the best area for a possible derecho with widespread wind damage has shifted south to include much of Northern NJ and NYC. The tornado threat also will probably run as far south as the NY/PA and NY/NJ border.

These are some of the highest SPC SREF severe probabilities I have ever seen in this area.

http://www.spc.noaa.gov/exper/sref/sref_matrix_hover.php?fhr=f039&startdate=2012072509&field=SREF_03HR_SVR_PROBS__#image

Link to comment
Share on other sites

I agree with Earthlight and Isotherm about the nature of the thunderstorms this evening and how it may go down in evolution. A significant wind damage event seems probable in our area this evening. The initial supercells this afternoon that form in N PA / C PA may struggle with tornadogenesis for you chasers out there. Anything tornadic this evening will not be chaseable not only for the location/timing but with their nature (fast / embedded in a line).

I agree about the tornado threat embedded in the line of storms. We could see some supercells and rotation in any MCS that forms with the locally backed low level winds.

Link to comment
Share on other sites

I agree about the tornado threat embedded in the line of storms. We could see some supercells and rotation in any MCS that forms with the locally backed low level winds.

Daytime supercells are most likely from N PA into NW CT before the wicked line comes through with increasing synoptic support. While this feature will have embedded tornadoes, the chaseable stuff will be out ahead.

Tornadogenesis will be tough but it is definitely doable N,C / NE PA into S NY/far NW NJ and W CT3-8pm.

Link to comment
Share on other sites

Archived

This topic is now archived and is closed to further replies.

  • Recently Browsing   0 members

    • No registered users viewing this page.

×
×
  • Create New...