St. Louis woke up this morning, Friday, April 17, to clear skies, comfortable air, and temperatures near 61°F. By this afternoon, the city is expected to surge into the upper 80s, with showers and thunderstorms possible after 2 p.m. A line of strong to potentially severe storms is on track for late afternoon into the evening, bringing a primary risk of damaging wind gusts and heavy downpours.
Afternoon Into Evening
Storms are most likely to fire up after 2 p.m. and ramp up in intensity through the late afternoon and early evening hours on Friday, April 17, 2026. According to the National Weather Service in St. Louis, the main concern is damaging straight-line winds, with a limited chance of brief tornadoes and occasional large hail in the strongest storms.
Late Night Into Saturday
Showers and thunderstorms are likely Friday night, and many forecasts show a stretch of widespread rain with embedded storms before 1 a.m. Some of those storms could drop heavy rain in a short time and trigger localized flooding. Once the front passes, temperatures take a sharp dive, with highs near the upper 80s on Friday falling into the low-to-mid 50s by Saturday morning, a drop of roughly 30 to 45 degrees in many spots.
Weekend Outlook
Saturday turns noticeably cooler and breezy, with highs only in the upper 50s and gusty northwest winds keeping it feeling brisk. Sunday looks brighter and milder, with sunshine returning and highs near the upper 60s. Forecasters at the National Weather Service in St. Louis also flag a modest chance for patchy frost early Sunday in low-lying, sheltered areas, so it is a good idea to protect tender plants if you keep them outside.
What To Do
Plan to move outdoor activities inside this afternoon and evening, or at least have a backup option ready. Avoid driving through standing water, and if a severe thunderstorm or tornado warning is issued, head to a small interior room or hallway away from windows. Bring in or secure loose patio furniture, charge your phones, and keep an eye on local forecasts and official warnings so you can move quickly if the weather turns in a hurry.
Earlier Coverage
We covered the warm start to the week in our April 15 update. For more background on how this pattern set up, see our earlier piece on the stormy finish. We will post updates if warnings are issued tonight.
