ST. LOUIS — A volatile weather pattern is set to bring severe thunderstorms, heavy rainfall, and a sharp temperature drop this week. The region faces multiple rounds of rain, starting with severe storms Tuesday night and Wednesday, followed by significant flooding risks later in the week. Cold temperatures could even lead to an outside chance of wet snow by Sunday.
Severe weather begins late Tuesday night, with a level 2 risk for thunderstorms in the northwestern part of the area. Quarter-sized hail is the primary concern.
Severe weather
By Wednesday, the threat escalates to a level 3 risk, with severe storms possible from midday into the evening. However, uncertainty remains regarding how Tuesday night’s storms will impact the atmospheric setup. If the morning is cloud-covered and damp, storm activity could be more limited in the afternoon. If the atmosphere remains undisturbed, strong winds and instability could fuel intense storms well into the evening.
Flooding
Beyond the storms, heavy rainfall becomes the next major concern. The cold front responsible for Wednesday’s storms will stall over southern Missouri and southern Illinois, leading to persistent rain through the weekend. Some areas could see 4 to 8 inches of rain, with isolated totals exceeding a foot. Flooding is likely, potentially extending as far north as the I-70 corridor.
As the storm system moves out, colder air will surge in next week, bringing near- or sub-freezing temperatures for several nights. There is even a slight chance of wet snow on Sunday, marking a dramatic shift from the severe weather earlier in the week.
Forecast Timeline:
- Tuesday Night: Level 2 severe weather risk, with a primary concern of quarter-sized hail.
- Wednesday: Level 3 severe weather risk from midday into the evening; intensity depends on morning conditions.
- Late Week into Weekend: Stalled front brings 4-8 inches (or more) of rain, with flooding possible in southern areas.
- Sunday: Potential for wet snow as colder air moves in.
