Severe Weather: April 24

Latest NAM forecast is on its' way online, and with that I will update the forecast for tomorrow's severe weather threat. Cold front will be draped across the plains from northwest Kansas to northern Wisconsin tomorrow evening. This will leave much,if not all, of the state of Iowa in the warm sector with temperatures well into the 80s and potentially 90s once again. Surface winds from the south will continue to bring in moisture, likely nearing 60 degree dew points along the front. This should yield CAPE values ~2000 J/kg, and with the rapid surface warming and mixing much like today we may near convective temperatures. It does appear that any capping should be overcome by 00z tomorrow across much of Iowa along the front. If storms are able to break any capping between 21z and 00z these will be more discrete, thus capable of significant hail; and a tornadic storm cannot be ruled out given some of the storm-relative shear values just ahead of the front. The more likely scenario will be several clusters of storms to develop along the cold front during the evening hours, likely congealing into one or more MCS's as the night progresses. The large hail and damaging wind threat is fairly good given the instability and eventual shear with the low-level jet during the nighttime hours. Much of the state will be at risk for severe weather, but areas of central and southwest appear more likely at this time.

Additional updates are likely tomorrow morning.

Beyond Friday's threat, both Saturday and Sunday do appear to have very good chances of thunderstorms across at least the southeast half of the state as the cold front stalls and lays across the state throughout the weekend. The threat for severe weather does also appear for both days, however, the risk does not appear significant at this time with mainly a large hail and damaging wind threat.