Jump to content
  • Member Statistics

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

Severe Threat June 11-13


Hoosier

Recommended Posts

Yeah, this event is starting to occur a bit sooner than I expected, although I agree with Alek that MN and IA will be the place to watch for the main show overnight.  This evening may be the appetizer.  Was a bit surprised to see these storms firing in northern IL when SPC was initially concerned for surface development and a possible watch downstate in IL a bit earlier this afternoon.  Of course these storms now are probably elevated.  Quarter inch hail report at Davis Junction in Ogle County IL from these developing cells.

Link to comment
Share on other sites

  • Replies 1.2k
  • Created
  • Last Reply

LOT's latest AFD seems to imply a few chances at some storms (even severe) tonight/overnight/tomorrow morning...before the main show tomorrow night, which they expect the greatest severe threat to be along and south of a Dixon-Chicago line.

Link to comment
Share on other sites

In some ways days like tomorrow are more dangerous than most tornado days. There is the potential for tornadoes with discrete cells or whatever forms within the line, which usually affect small areas, but then there's also what may be high-end damaging straight line wind potential for a much larger area.

Link to comment
Share on other sites

Lets see what happens... Had to frantically finish mowing my lawn.

 

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE CHICAGO/ROMEOVILLE IL
325 PM CDT TUE JUN 11 2013

ILZ008-010>013-112100-
DE KALB IL-DUPAGE IL-KANE IL-LEE IL-OGLE IL-
325 PM CDT TUE JUN 11 2013

...SPECIAL WEATHER STATEMENT...

AT 324 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
STRONG THUNDERSTORMS ALONG A LINE EXTENDING FROM 19 MILES NORTHWEST
OF MALTA TO SYCAMORE...MOVING SOUTHEAST AT 55 MPH.

NICKEL SIZE HAIL...FREQUENT CLOUD TO GROUND LIGHTNING...BRIEF HEAVY
DOWNPOURS...ARE POSSIBLE WITH THESE STORMS.

OTHER LOCATIONS AFFECTED...
KANE COUNTY COUGARS BALLPARK...NORTHERN ILLINOIS UNIVERSITY...

I-88 BETWEEN MILE MARKERS 82 AND 108.
I-39 BETWEEN MILE MARKERS 101 AND 110.

 

Link to comment
Share on other sites

I was checking the 12z NAM for Toledo, Ohio temp profile and parameters tomorrow. There is close to 2000 CAPE with a 0-6km shear of nearly 80 knots at 18z (2:00PM) tomorrow. Storm relative helicity is about 200m2/s2. EHI in northwest Ohio is up to 6. That 80 knots is insane stuff. I would tend to think the 0-6km shear (and possibly helicity) may decrease by some amount by the time convection fires.

I think anything that goes super cellular tomorrow afternoon will definitely be tornadic in this area 

Link to comment
Share on other sites

Perhaps, although the updraft helicity product from the WRF suggests the tornado threat would be high enough for a tornado watch with very high wind probs, also, given the low level shear, the derecho itself (if it does develop) may be more tornado friendly than some others we have seen.

 

0-3 km shear are forecast to be favorably normal to whatever gust front may develop. The actual magnitude itself (NAM and GFS) would be just below the preferred value for development of mesovortices on the leading edge. Of course these things can changed with subtle shifts in the environment during the day tomorrow. 0-1 km shear would suggest a few significant tornadoes are possible, especially near the IN border between 00 and 06z.

 

Probably a long winded way to say, the tornado threat looks about normal for your average derecho forecast.

Link to comment
Share on other sites

I think anything that goes super cellular tomorrow afternoon will definitely be tornadic in this area 

I think that 80 knots was a bit weird. The NAM forecast for 15z, 21z, and 00z didn't have that. Nevertheless, the warm front area could be a hot spot for a couple of tornadoes, and that could be near Toledo.

Link to comment
Share on other sites

I think that 80 knots was a bit weird. The NAM forecast for 15z, 21z, and 00z didn't have that. Nevertheless, the warm front area could be a hot spot for a couple of tornadoes, and that could be near Toledo.

 

NAM is definitely the higher end of guidance, but GFS and ECMWF both are 50+ kt 0-6 km as well. Nothing to scoff at.

Link to comment
Share on other sites

UGH.  There was time in my younger years where I used to look forward to these events.  Then last year's derecho happened at the end of June.  Our neighbor's tree landed on our deck, we were without power for a week, and temps were in the upper 90's that whole week!  Since then I have huge anxiety whenever I hear about pending severe events, especially one like this that sounds exactly the same as that one.  Be careful what you wish for, guys!

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...