Thursday/Friday storm discussion

Wednesday Evening - New model data suggests a potential for severe storms for Thursday evening ahead of the main low. Severe storms will be ongoing across much of Illinois and the mid-Mississippi River valley. However if storms develop from NE Missouri into Eastern Iowa, they may push across the Mississippi River by midnight Thursday night.

Wednesday Afternoon - While blizzard warnings have been posted for Northern Minnesota, tornado sirens are going off north of Abilene, Texas. These are all part of the same storm system that will move out of the Southern Plains tonight and enter the Midwest Thursday. Rainfall will start in the Rockford metro around daybreak Thursday with chilly temperatures in the 30s. Warm, moist air will be continuously pumped into the area during the day. Temperatures will steadily rise into the 50° range for Thursday afternoon with on & off showers and thunderstorms. As a warm front moves north of I-80 during the evening, our threat of severe thunderstorms will really materialize. Surface winds will howl out of the south at over 30mph with some gusts to 45 even without the presence of thunderstorms. If we throw a few storms out there Thursday night, severe wind gusts over 60mph will be observed. Storm motion will be straight out of the south at perhaps 55-65mph. Large hail won't be an extreme threat as our atmosphere will be fairly warm and above 32° at least to 10K feet. Wind shear will cause tornadoes across Missouri and Central Illinois during the afternoon. Should the warm front accelerate northward and move through the metro, a few rotating thunderstorms will be possible. While this system will produce a few strong tornadoes down south, it shouldn't be our biggest threat. Heavy rainfall will be possible with some locations seeing near one inch by afternoon. Forecast guidance suggests that if we receive more than 1.10 inches of rain in an hour, flash flooding will occur. Flash Flood Watches have been hoisted for Northern Illinois.

Graphics coming shortly.

In the meantime, Meteorologist Ryan Vaughn's at ground zero and has some cool tornado indicators on his blog. Click here to see it!