textproduct: Springfield

KEY MESSAGES

- Thunderstorms are expected through this morning with the focus across central Missouri. A few storms could be severe with damaging winds the primary threat.

- Another round of thunderstorms is possible this evening, this time with the focus across southern Missouri. Damaging winds and heavy rainfall will be the primary threats.

- Hot and humid conditions continue to the south of a cold front on today with far southwest Missouri having the best chance (50%) of seeing heat index values near 105 again.

SHORT TERM /THROUGH TONIGHT/

Issued at 1258 AM CDT Wed Aug 19 2026

Early this morning, clusters of showers and storms, some of which are strong to severe, were moving to the southeast as a frontal boundary slowly makes its way south through the Ozarks. The storms were following the upper level northwesterly flow with subtle shortwaves helping to enhance some of the clusters along with a 40-50kt LLJ making its way east across the region.

Thanks to the warm and moist air mass feeding these storms and modest wind shear, the convective clusters will be capable of damaging winds. In addition, heavy rain rates of 1 to 2 inches per hour can be expected where storms move over the region.

Storms will taper off through this morning, as convective outflow helps push the front southward through the region. This will help shift the hot and humid air mass further southwest for today. the warmest temperatures and heat indicies will be south of the front where the warmest and more humid air will reside. This will bring hot and humid conditions with heat index values approaching 105 where a Heat Advisory has been issue. North of the front/boundary, slightly cooler conditions can be expected.

Another round of showers and storms is expected again this evening with todays boundary helping to act as a focus. The boundary is likely to be across far southern Missouri near the Arkansas border by this evening. Storms forming here will have access to the hot, humid, unstable air mass south of the front and moderately strong wind shear. Supercells and convective clusters will both be possible, with damaging winds and heavy rainfall the primary threats and hail or a tornado as secondary threats. This afternoon/evenings showers and storms are to develop across far southern Missouri and slide south into Arkansas by around midnight tonight as the front gets a better push southward behind the upper trough moving through the Great Lakes.

LONG TERM /THURSDAY THROUGH TUESDAY/

Issued at 1258 AM CDT Wed Aug 19 2026

For thursday through the weekend and into early next week, the Ozarks will remain under the influence of upper level northwesterly flow on the eastern periphery of a strong ridge of high press over the Four Corners region. This will provide for a potentially active period of weather with daily shortwaves, fronts/boundaries and a fight between the cooler Canadian air masses and the heat of the southwestern Ridge.

As a result of this pattern, there will also be occasional chances for thunderstorms as impulses rotate around the ridge. This will be impacted however, by limited moisture flowing north through the Plains. Latest NBM PoP's remain quite low (20-40 percent or less) through the extended forecast. This keeps better confidence that some storms will be around but timing and location uncertainty is keeping the PoP lower.

Confidence remains good for cooler conditions Thursday into Friday with highs around 90. For the weekend, temperatures should see a slow climb back into the middle and upper 90s to start next week. This will all depend of weather we stay more under the influence of the cooler air masses or the hotter air from the ridge noses. If the warmer air makes its way into the region then we will see temperatures approach 100 degrees again. Current NBM forecast is a blend which does reflect a rather large gradient, hotter in the west and cooler in the east.

AVIATION /12Z TAFS THROUGH 12Z THURSDAY/

Issued at 615 AM CDT Wed Aug 19 2026

A cold front or weak boundary was sliding slowly south and east this morning bringing with it increasing cloud cover along with showers and storms. This is expected to continue through this morning with the showers moving to the east south east.

When rain or storms occur, expect ceilings and visibilities to become MVFR otherwise VFR flight conditions are anticipated.

SGF WATCHES/WARNINGS/ADVISORIES

KS...None. MO...Heat Advisory until 8 PM CDT this evening for MOZ093-101>105.