There certainly will be thunderstorms in the vicinity of Salt Lake City between 3 pm and 9 pm. The greatest threat of hail, lightning and such is north of Salt Lake City, but SLC and RES are in the threat zone — maybe 60% for RES in that window, with luck it will move through earlier rather than later. As the evening progresses this area of storms is expected to move north, individual storms moving NE, so probability of a delay at RES should decrease into the evening but wont be zero until until about 10-11pm I would say.
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