Current synopsis has a shortwave moving east out of the region which will give way to a surface ridge to our north that will set the stage for a rather chilly night, especially for those near I-70 where skies will be trying to clear out overnight. If they do, it should allow for radiational cool where temperatures will fall into the mid-teens. Farther south where cloud cover will likely exist throughout the night, temperatures won’t fall nearly as much and should remain the mid-20s. The majority of the region should remain dry overnight but there is a little concern those south of Carbondale may see a stray flurry or light freezing drizzle (as noted by the two simulated radar images posted above) but the best chances for wintry precipitation will exist farther south into Kentucky. I’ll continue to monitor radar trends throughout the evening.
As we start the work week, we’ll begin a warming trend which will undoubtedly give us our first taste of spring. Let’s start with Monday. Expect to see plenty of sun and highs rebounding into the upper 30s – low 40s thanks to southerly return flow behind the passing ridge that kept us cold overnight. Monday night will remain mostly clear and drop down into the low-mid 20s area wide.
Tuesday you can expect more of the same. We’ll continue to warm up to slightly above seasonal normals with high temperatures peaking in the upper 40s possibly even 50 in some spots. Some cloud cover should start to filter into the region Tuesday into Tuesday night due to mid-level moisture advection so I will suggest a slight chance of spotty showers (all liquid – no frozen precipitation). Model guidance aren’t in agreement with the NAM suggesting much higher QPF than the GFS and Euro. The Euro appears to be somewhat of a middle ground between the NAM/GFS solutions so I’ll keep that in forecast for now. Tuesday night lows shouldn’t drop off a whole lot given continued warm air and moisture advection into the region so I think upper 30s to lower 40s is a good range to go with for the time being.
Wednesday and Thursday will be the two warmest days of the week by far with high temperatures well above seasonal norms. Expect high temperatures on Wednesday to range from 60-65 degrees with overnight lows only falling into the lower-mid 50s. Thursday will see more of the same with highs reaching into the mid-60s. I mentioned yesterday that Wednesday would be the day to get out and enjoy the day with the concern of rain on Thursday but timing differences are quite evident in model guidance and there exists a possibility for rain, unfortunately. This happens every time we have a concern with the northern and southern streams phasing (coming together). Model guidance just does not handle these scenarios well. I’ll try to pin down some certainty with these chances as we move forward but Thursday into Friday still appears to bring the greatest likelihood for precipitation when a positively tilted shortwave and associated cold front sweeps through the region. This will bring with it much needed rain across parts of southern IL who are experiencing drought conditions. As noted earlier, timing differences still exist but currently expect the greatest likelihood for precipitation to develop Thursday night into Friday. Temperatures will likely fall rapidly behind the cold front and it’s possible we’ll see a wintry mix with post-frontal precipitation but it’s much too early to discuss any impacts with such a scenario. Regardless, expect temperatures to fall into the low-mid 30s overnight.