


Severe Storm Outlook Narrative (AC)
Issued by NWS
Issued by NWS
001 ACUS03 KWNS 160728 SWODY3 SPC AC 160727 Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0227 AM CDT Thu Oct 16 2025 Valid 181200Z - 191200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE ARK-LA-TEX...OZARKS AND MID MISSISSIPPI VALLEY... ...SUMMARY... Severe thunderstorms will be possible on Saturday across parts of the Ark-La-Tex, Ozarks and mid Mississippi Valley. A threat for tornadoes, damaging wind gusts and hail is expected to develop from the late morning into the overnight. ...Ark-La-Tex/Ozarks/Mid Mississippi Valley... A large-scale mid-level trough will move across the Great Plains on Saturday, as an associated jet streak moves into the Ozarks. Scattered thunderstorms will likely be ongoing just ahead of the trough at the start of the period, from eastern Oklahoma into central Missouri. To the south and east of this activity, moderate instability is expected to develop during the morning over much of the Ark-La-Tex and Ozarks. As surface temperatures warm across the moist sector, convective coverage is forecast to gradually increase. An MCS appears likely to form during the afternoon, with a relatively large cluster of storms moving eastward across southern Missouri, Arkansas and northern Louisiana. The MCS is expected to become organized and pose a severe threat across the region. Ahead of the MCS, forecast soundings during the mid afternoon have MLCAPE peaking between 1500 and 2000 J/kg, with 0-6 km shear in the 50 to 55 knot range. 0-3 km storm-relative helicity is forecast to increase to about 250 m2/s2 near the low-level jet in the late afternoon. This should support supercell development with tornado potential. Storms that remain discrete and interact with the low-level jet will have the greatest potential for tornadoes. Supercells should also be capable of large hail. Once the MCS becomes organized, a transition to linear mode could occur. If this were to happen, then the wind-damage threat would increase, and could become the greatest threat. Any severe threat should persist through the evening, and possibly into the early overnight period, as the MCS moves eastward across the central Gulf Coast states and Tennessee Valley. ...Lower Ohio Valley/Southern Great Lakes... A mid-level trough will move across the Great Plains on Saturday, as a belt of southwesterly flow remains from the mid Mississippi Valley into the Great Lakes. At the surface, a cold front will advance southeastward across the mid to upper Mississippi Valley, and Great Lakes region. A corridor of low-level moisture will be present ahead of the front with surface dewpoints in the lower to mid 60s F. This should allow for weak destabilization by afternoon. Thunderstorms will develop along parts of the front, and move eastward into the moist airmass. The models differ markedly on how much instability will develop across this moist airmass, which adds considerable uncertainty into the forecast. In spite of this, the combination of instability and moderate deep-layer shear should be great enough for an isolated severe threat. Line segments would be favored to produce damaging wind gusts. A few rotating storms will also be possible. ..Broyles.. 10/16/2025 $$