AREAS AFFECTED...CNTRL INTO NRN IL
CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE
VALID 192308Z - 200015Z
PROBABILITY OF WATCH ISSUANCE...40 PERCENT
SUMMARY...TSTMS INTENSIFYING ALONG THE MS RIVER BETWEEN MLI AND UIN
MAY MOVE OUT OF TORNADO WATCH 183 PRIOR TO 00Z. CONVECTIVE TRENDS
ARE BEING MONITORED FOR A POSSIBLE WW.
DISCUSSION...AS OF 2245Z...RADAR DATA INDICATED A CLUSTER OF
INTENSIFYING TSTMS FROM ROCK ISLAND AND MERCER COUNTIES TO HANCOCK
COUNTY IL. THE ANCHOR STORM OF THIS CLUSTER OVER HANCOCK COUNTY HAS
RECENTLY EXHIBITED RIGHTWARD PROPAGATION...SUGGESTING EVOLUTION INTO
A SUPERCELL. AREA VAD DATA AND MODEL-DERIVED FORECAST SOUNDINGS
INDICATE A ENVIRONMENT FOR UPDRAFT SUSTENANCE/ROTATION WITH A
MODERATELY UNSTABLE AIR MASS WHICH COINCIDES WITH A VERTICALLY
VEERING WIND PROFILE AND 40-45 KT OF DEEP-LAYER SHEAR. EXPECT
VERTICAL SHEAR TO FURTHER STRENGTHEN THROUGH THIS EVENING AS THE
EXIT REGION OF A 40-50 KT LLJ DEVELOPS NEWD INTO THE REGION. AS
SUCH...EXPECT THE POTENTIAL FOR ORGANIZED STORM MODES...INCLUDING
SUPERCELLS TO PERSIST THROUGH THIS EVENING AND POSSIBLY DEVELOP EAST
OF TORNADO WATCH 183 BY 00Z.
..MEAD/CORFIDI.. 05/19/2013
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...LOT...ILX...DVN...
LAT...LON 40899030 41498963 41838940 41708887 41218890 40478936
40248995 40399033 40899030
