Jim Martin

Great sunset this evening.

Might be seeing an uptick in the storm activity in the Chicago area/Northwest Indiana.

Text discussion from WPC... GIVEN THE LEVEL OF SHEAR AND VERY IMPRESSIVE THERMODYNAMICS...THE ENVIRONMENT OVER THE NEXT SEVERAL HOURS WILL BE HIGHLY CONDUCIVE FOR A STRONG MCS TO EVOLVE AS CONVECTIVE CLUSTERS MERGE AND CONSOLIDATE INTO A LARGER CONVECTIVE COMPLEX. THIS WILL BE AIDED BY SHORTWAVE DYNAMICS AND WARM ADVECTION AHEAD OF THIS SURFACE WAVE WHICH IS TRAVERSING A WAVY QUASI-STATIONARY FRONT. A SOUTHWEST LOW LEVEL JET IS FORECAST BY THE LATEST RAP GUIDANCE TO INCREASE TO NEAR 50 KTS BY 06Z AHEAD OF THE SURFACE WAVE..AND THIS SHOULD STRONGLY ENHANCE THE LARGER SCALE FORCING AND THERMODYNAMIC SUPPORT FOR THE CONVECTIVE COMPLEX. EXPECT RAINFALL RATES OF UP TO 3 INCHES/HR GIVEN THE DEEP COLUMN OF MOISTURE AND STRONG INSTABILITY ALONG THE FRONT. RAINFALL AMOUNTS THROUGH 06Z OF AS MUCH 4 TO 6 INCHES WILL BE POSSIBLE AND ESPECIALLY WHERE CELL-MERGERS AND SOME EPISODIC TRAINING OF CONVECTIVE CLUSTERS OCCUR. THESE AMOUNTS ARE LIKELY TO RESULT IN FLASH FLOODING...WITH SOME OF IT SIGNIFICANT GIVEN RECENT HEAVY RAINFALL AND THE URBAN CORRIDORS AREAS...INCLUDING THE CHICAGO METROPOLITAN AREA. THIS WILL LIKELY BE A LONG-LIVED MCS..AND ADDITIONAL MPDS WILL BE ISSUED ACCORDINGLY.

South of Irwin, Illinois currently.

From IWX... .Update... Issued at 908 PM EDT Fri Jul 21 2017 Mesohigh bubble from early morning convection continues to slowly modify but will accelerate shortly as swrly low level jet escalates appreciably now through midnight. As a result significant low level theta-e ridge splayed out through IL/wrn IN will advect abruptly northeast. Thus evolving linear convection over wrn IL expected to grow further upscale as it comes east with several sig reports of wind gusts/damage. Additional downstream storms along the newd progressing warm front pose a near term isolated severe risk over far wrn zones currently in SV.429. Downstream watch expansion likely later this evening based on recent CAMS guidance.

To add insult to injury, this from the Weather Prediction Center.

Tornado Debris Signature.

South of Chicago and west of Kanakee currently.

West of Iowa City currently.

Current radar of severe storm in eastern Iowa.

Hodograph currenty at Des Moines, Iowa.

91° air temperature & 80° dewpoint currently at Iowa City, Iowa.

Cross your fingers Rockford does not get hit hard again later this evening and tonight.

lotchat 2017/07/21 4:10 PM iembot Rockford [Winnebago Co, IL] LAW ENFORCEMENT reports TSTM WND DMG at 2:53 PM CDT -- NUMEROUS CALLS OF TREES AND POWERLINES DOWNED THROUGHOUT THE CITY