Area Forecast Discussion

KEY MESSAGES

- Slight Risk (2 of 5) for strong to severe thunderstorms this afternoon and evening. Hail up to the size of golf balls and wind gusts of 60-70 mph will be the primary hazards, with a secondary risk of tornadoes.

- Additional thunderstorm chances on Saturday and Sunday will pose a risk for flash flooding due to recent heavy rainfall, elevated streamflows, and saturated soils. An associated severe weather risk may also develop.

SHORT TERM /THROUGH TONIGHT/

Issued at 204 AM CDT Thu Jun 11 2026

Synoptic Overview:

An occluded upper-level low embedded within a broader shortwave trough was pivoting northeast through Canada toward the Hudson Bay early this morning, dragging an attendant surface front through the Midwest and into the Plains. A surface low was situated across southwest Kansas, slowly pushing east. Convection has remained more robust across portions of northern Missouri and Illinois but has struggled to survive farther to the southwest with more significant inhibition.

Gusty Winds this Morning:

As the surface low across Kansas shifts east this morning, the pressure gradient will tighten, and winds will increase. Hi-res guidance is also more bullish on the maximum gust potential in response to this increasing gradient, so we have bumped up our forecast winds and gusts this morning. Southwesterly gusts of 40 to 45 mph are likely west of Highway 65. Winds should start to relax throughout the afternoon as heating increases and the pressure gradient washes out.

Warm and Muggy Today:

Dew points will remain high today, contributing to continued humid and sticky conditions. Temperatures will be similar today compared to yesterday's in the upper 80s to low 90s, but an even greater influx of moisture will push heat indices a few degrees higher. Afternoon heat indices are forecast to be in the 95 to 105 degree range, which is just shy of Heat Advisory criteria. Nevertheless, vulnerable populations and those sensitive to heat illnesses may still be susceptible.

Severe Thunderstorm Risk this Afternoon/Evening:

Environment: The larger shortwave will dig and pivot through the Plains and into the Midwest throughout the day today, pushing the aforementioned cold front east/southeast into southeast Kansas and the Missouri Ozarks. A juiced thermodynamic profile featuring steep mid-level lapse rates (7-8 C/km) and ample MUCAPE (3000-4000 J/kg) within a zone of enhanced 850 mb and mid- level flow will support robust updrafts and convection capable of producing large hail and damaging wind gusts along the front. Notably, CAMs have shifted the corridor of the greatest shear slightly to the northwest over the last 12-24 hours, therefore decreasing the available shear for storms in our CWA. Guidance has 0-6 km bulk shear values progged around 30 to 35 kt across west-central Missouri and eastern Kansas, which would still be sufficient for robust, organized updrafts capable of producing severe weather, but may limit the very large hail potential for those areas.

Timing: Convective initiation looks to begin across eastern Kansas and west-central Missouri sometime between 2 PM to 5 PM. Storm mode may initially favor a brief period of supercells, but with deep- layer flow largely parallel to the front, storms should quickly grow upscale into clusters and/or line segments. Overall, guidance is in fairly good agreement with the timing/speed of these storms as they push southeast through the forecast area. They depict the line of storms approaching the I-44 corridor between 5 PM and 9 PM, then through south-central MO and the eastern Ozarks between 9 PM and 12 AM. The front looks to slow down somewhat as it moves into southeast Missouri, so a few storms may linger across extreme southern/south- central Missouri into the midnight hour, but the severe threat will also be diminishing at that time.

Hazards: If supercells form, hail up to the size of golf balls, gusts up to 70 mph, and an isolated tornado will be possible across west- central Missouri and southeast Kansas. As mentioned previously, however, confidence in this very large hail being realized has decreased, and the window for occurrence will likely be small. As storms shift southeast toward the I-44 corridor, hail to the size of quarters and gusts of 60 to 70 mph will be the primary hazards, with a secondary risk for a brief, weak tornado. Across south-central Missouri and the eastern Ozarks, storms are expected to gradually diminish in intensity, but a few instances of hail to the size of quarters and 60 mph wind gusts cannot be ruled out. Heavy downpours with high rain rates (1-2"/hr) will accompany these storms, but the progressive nature of the front limits the risk of widespread flooding. Sensitive or already- inundated basins may still be at risk of localized flash flooding, however.

LONG TERM /FRIDAY THROUGH WEDNESDAY/

Issued at 204 AM CDT Thu Jun 11 2026

Cool and Dry Friday:

Temperatures--and especially dew points--will tumble behind the front on Friday, making way for much cooler, drier, and more pleasant- feeling conditions. Look for high temperatures in the low 80s and no precipitation chances, at least until late Friday night.

Flooding & Severe Potential Saturday-Sunday:

Ensembles show the upper-level pattern becoming more zonal by the weekend, allowing the front to lift north into southern Missouri and southeast Kansas as a warm front and bring warm, moist air back to the region. Global models do show general agreement in breaking out convection along the front in an unstable environment, but their overly wide QPF footprint is likely leading to artificially inflated PoPs-- at least for specific times and locations on Saturday. That said, confidence is high that there will be showers and storms throughout the day (75-95% chance), but an all-day washout remains questionable at this time. By Saturday night, an upper-level trough is poised to dig through the Great Lakes region and Midwest, dragging a cold front through the Missouri Ozarks. Additional convection is likely to form along this boundary given the moist, unstable environment under a belt of enhanced 500 mb flow. Precipitation chances remain high (80-90%) late Saturday night into Sunday morning. These repeated rounds of rain, along with saturated soils and already-elevated streamflows will open the door to more flooding potential. The Weather Prediction Center as maintained its Slight Risk across the entire forecast area.

NBM Rainfall Probability of Exceedance Saturday through Sunday:

Prob >1 inch: 50% to 85% Prob >2 inch: 25% to 60% Prob >3 inch: 0% to 40% Prob >4 inch: 0% to 30%

The highest probabilities are currently across far western MO and eastern KS.

Severe weather cannot be ruled out with this second round of storms, but the better potential appears to be closer to the 500 mb jet across northern Missouri, eastern Kansas, and Iowa. Machine learning and AI guidance generally supports a more northerly signal as well, but this risk will be better assessed in future forecast updates.

Next Week:

Precipitation chances become more scarce (25% or less) by Monday as the front pushes south into Arkansas. Even cooler temperatures are progged to filter in behind it; in fact, NBM percentile data support high temperatures around 10 degrees below climatological averages by Monday, followed by a gradual warmup.

AVIATION /12Z TAFS THROUGH 12Z FRIDAY/

Issued at 600 AM CDT Thu Jun 11 2026

A patch of scattered to broken MVFR ceilings were ongoing over the SGF terminal at the start of the TAF period; otherwise, VFR conditions will prevail with clear skies or a few high clouds.

South-southwesterly winds will increase this morning, particularly across western Missouri and eastern Kansas. Winds will be sustained around 15 to 20 kt with gusts between 25 to 35 kt throughout the morning before gradually diminishing during the afternoon.

A line of showers and thunderstorms along a cold front will move through southwest Missouri this afternoon and evening, likely bringing a period of reduced ceilings and low visibilities due to heavy rainfall. There is a chance this activity lingers around the BBG terminal a bit longer into the early overnight hours as the front slows down, so have included a PROB30 group for additional chances beyond 06Z.

SGF WATCHES / WARNINGS / ADVISORIES

KS...None. MO...None.