Marina
St. Louis is set for a hot and dry start to the week, with daily highs reaching into the low to mid-90s. Most of the area will stay dry through midweek, though a few isolated storms may develop by Thursday afternoon.
A stronger cold front will move in by Friday, bringing higher rain chances and much-needed relief from the intense heat.
Residents should prepare for several days of above-average temperatures before cooler, more seasonable weather arrives over the weekend.
7-Day Weather Forecast
| Day | Forecast Summary | High / Low | Rain Chance | Key Notes |
|---|---|---|---|---|
| Monday Night | Partly cloudy and mild | Low ~70°F | 10% | Calm night with light winds |
| Tuesday | Hot, mostly sunny | High ~93°F / Low ~69°F | 10% | Heat index near upper 90s |
| Wednesday | Sunny, very warm | High ~94°F / Low ~68°F | 5% | Dry with strong sun |
| Thursday | Hot, scattered late storms | High ~92°F / Low ~70°F | 30% | Afternoon/evening storms possible |
| Friday | Cooler, rain chances increase | High ~86°F / Low ~66°F | 40% | Cold front arrives |
| Saturday | Seasonably mild, partly cloudy | High ~85°F / Low ~65°F | 25% | Pleasant with light winds |
| Sunday | Mild with possible showers | High ~84°F / Low ~64°F | 30% | Comfortable, unsettled at times |
Tonight and Tuesday
Skies will stay partly cloudy tonight, with temperatures holding around 70°F. Winds remain light, making for a mild and comfortable evening.
On Tuesday, expect another scorching day with highs near 93°F. Heat index values could push into the upper 90s, so residents should avoid extended time outdoors during the afternoon hours. The air will be dry, keeping storm chances low.
Wednesday: Peak Heat of the Week
By Wednesday, the heat peaks with highs reaching 94°F under sunny skies. Conditions will stay dry, but humidity levels will make it feel sticky at times. Those sensitive to heat should take precautions, as overnight lows remain warm near 68°F, giving little relief.
Thursday: Transition Day
Thursday begins hot again, with highs near 92°F. However, the weather pattern shifts as afternoon and evening storms become possible. While not everyone will see rain, some areas may get brief downpours, lightning, and gusty winds.
It will still feel warm and humid, but signs of change will begin to show.
Friday: Relief Arrives
A cold front sweeps through Friday, lowering daytime highs into the mid-80s. Along with cooler air, rain chances increase to around 40%, offering the best opportunity all week for widespread showers and storms. Behind the front, humidity levels start to ease.
Weekend Outlook
1. Saturday
Expect a comfortable day with highs near 85°F and lows around 65°F. Skies will be partly cloudy, and while a stray shower is possible, most of the region should stay dry.
2. Sunday
The weekend closes with slightly cooler conditions. Highs reach 84°F, with mild overnight lows in the mid-60s. Scattered showers may develop, but overall it will be a comfortable end to the week compared to the early heatwave.
Heat and Health Precautions
The early-week heat poses some challenges. With highs in the 90s and lows staying close to 70°F, residents may struggle to find relief. Here are some safety reminders:
- Stay hydrated: Drink water regularly, even if you don’t feel thirsty.
- Limit outdoor activity: Especially between 11 a.m. and 4 p.m. when the sun is strongest.
- Protect your skin: Wear sunscreen, hats, and sunglasses to avoid sunburn.
- Check on vulnerable groups: Elderly individuals, children, and pets need extra care in hot conditions.
Rain and Storms: What to Expect
While most of the week stays dry, Thursday and Friday bring a shift.
- Thursday: Spotty afternoon and evening storms, localized downpours possible.
- Friday: Widespread showers and thunderstorms, better cooling effect.
- Weekend: Light showers linger, but severe storms are not expected.
No widespread flooding is forecast, but localized street flooding could occur in heavy downpours.
Counties Affected
This forecast applies to St. Louis City and County as well as surrounding Missouri and Illinois counties, including:
- Missouri: Franklin, Jefferson, Lincoln, Madison, Perry, Phelps, Pike, Reynolds, St. Charles, St. Francois, Ste. Genevieve, Warren, Washington, Crawford, Gasconade, Iron.
- Illinois: Madison, St. Clair, Monroe, Jersey, Clinton, Bond, and surrounding areas.
Residents across these counties should plan for heat early and rain potential later in the week.
St. Louis faces a week of two halves. The early days bring intense heat and mostly dry conditions, with highs in the 90s and warm, sticky nights.
By Thursday and Friday, storm chances rise, and a cold front finally ushers in cooler, more comfortable weather for the weekend.
For now, residents should focus on heat safety measures, but look forward to a refreshing break from the heat as rain showers arrive later in the week.