A stalled frontal boundary coupled with an excessively moist atmosphere makes for a wash of a weekend as we monitor waves of heavy, widespread showers and t’storms. A Flash Flood Watch remains in effect for the entire viewing area until Sunday night with a Flash Flood Watch remaining for locations south of I-44 in MO and I-64 in IL through midday.
On this Saturday morning, Round 1 of heavy showers/storms eases by midday before another heavy round of showers/storms moves in late afternoon-tonight. This second round is worth watching for a severe storm threat, especially south of St. Louis where we could see damaging wind gusts. More widespread showers/storms are around for the first half of Sunday with more scattered showers/storms Sunday afternoon/evening. In total, widespread rainfall amounts of 3-6″ for this weekend remain on target with isolated spots pushing 7″ plus. Heaviest is likely south/southwest of St. Louis Metro. The trouble-maker front finally pushes through Sunday evening as a cold front, bringing temps down overnight and into Monday.
Flash flooding along area roadways remains the big risk today, but our focus shifts to local rivers/creeks next week as they play catch up. Current indications show that major flood potential exists for the Big River, Bourbeuse, Meramec, and Kaskaskia Rivers as they crest the first half of next week.
-Anne Elise Parks, @anneeliseparks