I'm going to focus on the rest of the work week and its' potential for severe weather before I get into the weekend in a later post. Currently the surprise event may be coming into shape for tomorrow evening across parts of the plains. A majority of models had indicated a shortwave that would move across the plains states during the day tomorrow and be across Iowa by the evening hours. However, many of the models had not initiated precipitation due to the stout inhibition (capping) that is in place. Some of the more recent model runs had finally broken this capping inversion and initiated some fairly heavy precipitation across parts of southern Iowa. So a quick overview of tomorrow's potential setup:
A warm front will likely be pulled eastward through the state during the early afternoon hours Thursday, leaving warm southerly flow to enter much of the western half of the state. Temperatures likely into the 80s and dew points in the upper 50s are likely, leaving 1000-1500 J/kg of CAPE over much of western Iowa and surrounding areas. Given other lower level temperatures, a capping inversion should be present for much of the day. With strong heating and mixing likely to occur, there appears to be a small probability that this inversion would be wore away and surface based convection could occur. Convective development would likely be aided by the 500hPa shortwave and associated vorticity maxima. Given marginal wind shear, any discrete storms may be able to be supercellular in nature; while more of a multicellular large hail threat may be more likely. An interesting setup nonetheless that will be monitored closely as we enter the day tomorrow and continue through the afternoon. If I were willing/able to chase I think the target area to hang out would be the Shenandoah, IA area. Additional updates are likely if the severe weather threat continues to materialize.
As for Friday, a cold front will push into the state from the northwest; in which very warm (potentially record) temperatures and dew points near 60 are likely to be in place. This should once again give way to 1000-2000 J/kg of CAPE across parts of Iowa and adjoining areas. It does once again appear to be capped as well, at least for regions ahead of the cold front. The most likely solution would be for elevated thunderstorms to occur along or just behind the front, capable of large hail through the evening and early nighttime hours across the western and northern thirds of the state. If temperatures are able to warm enough to initiate surface convection, there is the potential for discrete storms just ahead of the front which could be supercellular. Hard to believe we are talking about two days straight with capping issues in late April in Iowa, but we'll take what we can get for severe weather chances this early in the season. More details on Friday's threat in later updates after Thursday's potential becomes more defined.
Either way, enjoy the well above average and near record temperatures across the state the next two days!!
