There is a threat of thunderstorms this evening and later tonight as April comes to a close. The more numerous showers and storms are most likely to roam through western and northwest central Indiana this evening and through 12 a.m.
A warm front is lifting north late in the day and will continue to do so for the rest of the night. While storms are possible near and north of the front, the threat for rain will diminish late - perhaps after 3/4 a.m. as the front heads north.
A few gusty storms could swipe the area at or before 12 a.m. but the more active severe weather threat will remain west through sunrise. Rainfall coverage may reach 30% areal coverage before lowering toward sunrise. Again, most likely the target will be west/northwest portions of central Indiana.
Unstable air is only one ingredient in getting thunderstorms to fire up and become severe. Added ingredients are necessary like strong upper-air support (jet stream), a wind shifting front and a low pressure at the surface and aloft. Most of these ingredients are lacking here but not out west. Several severe storms have produced tornadoes in eastern Oklahoma, northwest Arkansas and southwest Missouri. The Storm Prediction Center late day included a 'moderate' risk for severe storms Tuesday evening. Ongoing and additional storms will be possible for the next several hours.
WARM FRONT COMING
The warm front is moving north from southern Indiana and temperatures are surging. North of the front only 40s in northern Indiana but by 6 p.m., the temperatures have climbed into the lower 80s downstate!
The surge north of the front later tonight will lead to a very warm open to May. With limited showers and thunderstorms in the forecast Wednesday, area-wide temperatures are likely to near or surpass the 80-degree mark!
The daily rain chance is continuing but many rain-free hours are once again expected Wednesday just like Tuesday. Thursday is still looking like the day that rain could be more wide-spread. We will monitor.