[MCD] SWOMCD

Thu Jul 20 10:20:30 UTC 2006

ACUS11 KWNS 201019
SWOMCD
SPC MCD 201018 
MIZ000-OHZ000-INZ000-ILZ000-201145-

MESOSCALE DISCUSSION 1579
NWS STORM PREDICTION CENTER NORMAN OK
0518 AM CDT THU JUL 20 2006

AREAS AFFECTED...NE IL...NRN IND...SW LOWER MI

CONCERNING...SEVERE THUNDERSTORM WATCH 625...

VALID 201018Z - 201145Z

A LARGE-SCALE BOW ECHO IS BEGINNING TO TURN SEWD AND THE SEVERE
THREAT SHOULD INCREASE OVER ECNTRL IL AND NWRN IND OVER THE NEXT FEW
HOURS. WIND DAMAGE WILL BE THE PRIMARY THREAT BUT HAIL WILL ALSO BE
POSSIBLE WITH THE STRONGER CELL ELEMENTS. A WW MAY BECOME NECESSARY
SOUTH OF WW 624 AND WW 625 WITHIN THE NEXT COUPLE HOURS.

WATER VAPOR IMAGERY CURRENTLY SHOWS THE LARGE-SCALE BOW ECHO ON THE
NERN EDGE OF A UPPER-LEVEL RIDGE AXIS. RUC DATA SUGGESTS WINDS ALOFT
TURN NLY ACROSS ERN IL AND IND WHICH IS LIKELY RESULTING IN A TURN
OF THE LINEAR MCS TO THE SOUTHEAST. MODERATE INSTABILITY CURRENTLY
EXISTS ACROSS CNTRL IL AND NERN IND AND FURTHER DESTABILIZATION
SHOULD OCCUR AHEAD OF THE MCS AS THE SUN COMES UP. IN ADDITION...A
50 KT MID-LEVEL JET BEHIND THE CONVECTIVE SYSTEM WILL CONTINUE ESEWD
ALLOWING DEEP LAYER SHEAR TO INCREASE. THIS COMBINED WITH STEEP
MID-LEVEL LAPSE RATES SHOULD CONTINUE A THREAT FOR WIND DAMAGE
ESPECIALLY NEAR THE APEX OF THE BOW. HAIL WILL ALSO BE POSSIBLE WITH
THE STRONGER CELLS EMBEDDED IN THE LINE.

..BROYLES.. 07/20/2006

...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...

ATTN...WFO...IWX...GRR...IND...LOT...ILX...DVN...

40048605 39818796 40058918 40598982 41498928 41758739
42428616 42568537 42048454 41148455 

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