Above is from the WRFn Model from the University of Illinois. This shows that very warm if not hot temperatures will be returning to the state ahead of the cold front that is forecast to move through on Wednesday. It shows 90s across SW Iowa, with 80s covering most of the state except the NE where readings will be in the upper 60s to mid 70s. GFS MOS data goes along with this as well. MOS projects 91° for Shenandoah on Tuesday, with 88° at Council Bluffs and Red Oak. MOS shows a few 90s possible over SE Iowa as well, Muscatine, Washington and Fort Madison to name a few have projected highs Tuesday at or above 90°

Above is the CAPE and CIN (Capping Layer) values from the same model WRFn at the same time as above (5pm Tuesday). It shows CAPE’s well over 5000 J/kg over the southeastern half of the state with the highest amounts over 6000. Below that is the capping layer and it shows little if any cap across the highest CAPE areas. This means that the atmosphere will likely be VERY unstable on Tuesday and any thunderstorm that develops Tuesday afternoon into the evening will have no problem becoming severe. The other WRF model from UIUC (WRFx) that goes through Tuesday had lower CAPE’s around 4000-4500 J/kg, but still it will be an interesting day across the state. It will truly feel like a summer preview once again nearly a month after the last 80° temps graced the state in early April