Narrative:

Nexrad WX radar showed a cell of extreme precipitation 10-12 mi west of the polar arrival for dtw. Numerous aircraft beyond these 2 deviated off the polar arrival which was showing clear and into the moderate and extreme WX that was painting west of the arrival. It was a rapidly moving system and nexrad was 10-12 mi lagging behind the actual WX.

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Original NASA ASRS Text

Title: ZOB CTLR EXPRESSED CONCERN REGARDING NEXRAD WX INFO AND ITS ABILITY TO KEEP UP WITH WX MOVEMENTS AND PROVIDE ACCURATE INFO FOR CTLRS.

Narrative: NEXRAD WX RADAR SHOWED A CELL OF EXTREME PRECIP 10-12 MI W OF THE POLAR ARR FOR DTW. NUMEROUS ACFT BEYOND THESE 2 DEVIATED OFF THE POLAR ARR WHICH WAS SHOWING CLR AND INTO THE MODERATE AND EXTREME WX THAT WAS PAINTING W OF THE ARR. IT WAS A RAPIDLY MOVING SYS AND NEXRAD WAS 10-12 MI LAGGING BEHIND THE ACTUAL WX.

Data retrieved from NASA's ASRS site as of January 2009 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.