AREAS AFFECTED...IA...SE MN...SRN WI...IL
CONCERNING...TORNADO WATCH 298...
VALID 122340Z - 130115Z
THE SEVERE WEATHER THREAT FOR TORNADO WATCH 298 CONTINUES.
SUMMARY...A SEVERE THREAT IS LIKELY TO CONTINUE ACROSS WW 298 OVER
THE NEXT FEW HOURS. TORNADOES...WIND DAMAGE AND LARGE HAIL WILL BE
POSSIBLE WITH THE MORE INTENSE CELLS.
DISCUSSION...THE LATEST SFC ANALYSIS SHOWS A 1002 MB LOW OVER NW IL
WITH A QUASI-STATIONARY FRONTAL BOUNDARY EXTENDING ESEWD ACROSS NE
IL INTO NRN IND. A LAKE BREEZE BOUNDARY IS LOCATED SW OF CHICAGO
WHERE LOW-LEVEL CONVERGENCE IS MAXIMIZED AND A CLUSTER OF SEVERE
STORMS IS ONGOING. STORM COVERAGE HAS MARKEDLY INCREASED ACROSS NRN
IL AND SE WI OVER THE LAST HOUR AHEAD OF AN APPROACHING SHORTWAVE
TROUGH IN THE UPPER MS VALLEY. THE HRRR HAS SHOWN THIS
INTENSIFICATION AND GRADUALLY MOVES A DEVELOPING LINEAR MCS ESEWD
TOWARD LAKE MI OVER THE NEXT 1 TO 2 HOURS. THIS CONVECTIVE SYSTEM
SHOULD BE ASSOCIATED WITH DAMAGING WIND GUSTS AND SOME TORNADOES.
FURTHER TO THE WEST...A CLUSTER OF SEVERE STORMS IS ONGOING IN NE IA
EXTENDING NWD INTO FAR SE MN AND SW WI. THIS ACTIVITY IS LOCATED TO
NORTH OF A SFC LOW AND IS BEHIND A COLD FRONT MOVING THROUGH CNTRL
IA. IN SPITE OF THIS...SFC DEWPOINTS ARE AROUND 70 F AND MLCAPE
VALUES ARE ESTIMATED IN THE 1000 TO 2000 J/KG RANGE. THIS COMBINED
WITH 0-6 KM SHEAR VALUES AROUND 40 KT SHOULD CONTINUE TO BE
SUPPORTIVE OF SUPERCELLS AND TORNADOES. LARGE HAIL WILL ALSO BE
POSSIBLE WITH THE MORE INTENSE ROTATING STORMS.
..BROYLES/HART.. 06/12/2013
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...LOT...ILX...MKX...DVN...ARX...MPX...DMX...
LAT...LON 40858984 41409229 42209420 43749378 44069167 43458859
42318793 41148800 40738899 40858984
