Officials say some Utah residents felt the largest aftershock yet since the 5.7 magnitude quake hit in March. The University of Utah Seismograph Stations reports Tuesday night's "light" earthquake of magnitude 4.2 was in the northwester Salt Lake Valley near the town of Magna. Officials say the aftershock was felt in the Wasatch Front region. University of Utah Seismograph Stations has recorded 1,247 aftershocks from the March 18 earthquake. Four others have had a magnitude of at least 4. Experts say more aftershocks are expected in the coming weeks and should become less frequent.