Saturday should be a tranquil day with only slightly above normal temperatures ahead of the next weather system. Things get rather interesting on Sunday across Central IL as a northern stream system drops south and attempts to phase with a southern stream system. This does appear to be a handoff of energy scenario, in which the weaker system will likely be absorbed into the more dominant system. Right now it appears that the southern stream system will be more dominant with a strong surface low developing along a well defined barocolinic zone in the Tennessee Valley Region. The question remains at this time exactly when this handoff of energy takes place as well as the strength of the northern stream system that will be moving southeast through Central IL. Given the available gulf moisture as well as the proximity to this baroclinic gradient, Central IL has a shot at a surprise middle of March snow event. While there is still considerable uncertainty with regard to the track, strength, precip-type/transition time, and amounts; it currently appears likely that some portions of Central IL will see measurable snow. More to come on this system as details get ironed out.
Sunday’s system will likely help to carve out a fairly deep trough across Central IL, which will effectively keep temperatures below normal through at least the middle of next week. Highs tomorrow will be in the mid to upper 40s across the north with temps creeping into the low 50s across the south. Sunday may have a wide spread of temperatures with areas receiving precipitation and abundant cloud cover likely only making it into the mid to upper 30s. Locations outside of the area of precip will likely make it into the mid to potentially upper 40s in spots. Temps will continue to cool to start the week with highs on Monday likely in the upper 30s to low 40s area wide. Tuesday will likely be the coldest day of the week with highs in the mid 30s across the north with upper 30s across the south. Temperatures will warm a couple degrees from the previous day on Wednesday, albeit temps will still be below normal for mid March. Expect lows in the 20s across the board from Sunday night through Tuesday Night with temps dropping into the lower 20s Tuesday night. With the area being under the influence of surface high pressure, expect dry weather to prevail through the end of the 5 day period.