Jump to content
  • Member Statistics

    17,606
    Total Members
    7,904
    Most Online
    ArlyDude
    Newest Member
    ArlyDude
    Joined

June 17th-22nd severe threat


Recommended Posts

Great first post...welcome to the forum!

Setting up for an intense afternoon in Nebraska. Some strong CAPE and significant LI values but what really intrigued me was the wind profile. It looks like the trough will continue to amplify throughout the afternoon due to the WAA at the surface and the CAA aloft. That means stronger PVA across the central plains which means the potential for stronger supercells if the cap holds in place long enough for discrete cells to fire!

dfek4n.jpg

Link to comment
Share on other sites

  • Replies 1.3k
  • Created
  • Last Reply

There is a significant weakness in the windfields around 800mb that is creating a mega-kink in the hodographs east of where the current tornadic supercell is. In fact that supercell happens to be in the only area that has high enough helicity and low enough LCLs for tornadoes... kinda splitting the uprights there. I'd go ahead and argue that will be the storm of the day given the hodograph issues further east and LCL issues further south. I'm more confident than usual about this, but as always I'll put up the disclaimer that I could be wrong so you guys won't hate me if tornadoes start dropping all over the place later.

I think that it looks like it will be the only storm for now, but looking at magic hour for the mid-west, about 00Z, the RUC is showing some interesting predictions. It looks like NE Nebraska will be in a region of strong upper-level divergence along with increasing helicity values. Also, at 850 hPa there is significant meridional flow which is advecting warm gulf moisture into the region. I think this will provide the necessary energy needed for a discrete cell to break the cap and verify the PDS watch.

Link to comment
Share on other sites

I've been confused on backing and veering all this time.

I used to have trouble remembering which meant WAA and which meant CAA until my professor told me to remember it by the phrase, "back in time, it was cold." So backing winds=CAA, verring winds=WAA.

Link to comment
Share on other sites

I think it's the first time that a PDS severe thunderstorm watch and PDS tornado watch have ever been out at the same time. Usually you need a derecho for a PDS severe thunderstorm watch and a major tornado event for a PDS tornado watch. Rarely do the two occur simultaneously, though 2/5/08 could have qualified.

Link to comment
Share on other sites

Does this mean that it's now standard that there will be a PDS added to a severe thunderstorm watch when all the hail and wind probs are high?

There is no standardization for a PDS. It is completely forecaster-dependent, though I know for tornado watches you usually need a 60% or higher F2+ tornado probability to see PDS.

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...