In a post about 2 hours ago, I noted that thunderstorm development was likely across northeast Nebraska and northwest Iowa and that a Tornado Watch would likely be issued by 4pm. Well, we still expect thunderstorms to form rapidly and we still expect a Tornado Watch to be issued for this same region, however thunderstorm development has not yet occurred.
This is mainly due to the presence of a strong capping inversion across the region. The longer the cap holds, the more unstable the air beneath it is becoming, which means thunderstorm development will be that much more explosive once the cap breaks.
At this time, it appears that conditions in the middle and upper-atmosphere will become more favorable for the cap to be broken by 6 or 7pm CDT. Once developed, thunderstorms will move East to East/Northeastward. Particularly severe and/or well organized storms may deviate to the East/Southeast once they mature.
Very large hail (perhaps in excess of 2 inches in diameter), damaging winds and tornadoes are all possible with severe storms in this region this evening. A few of the tornadoes could become strong and/or long tracked.
If you live in the region, please remain alert and be sure to listen to NOAA Weather Radio or another trusted source for later statements and possible warnings.
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