SPC AC 140600 Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 0100 AM CDT Fri Mar 14 2025 Valid 151200Z - 161200Z ...THERE IS A MODERATE RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF LOUISIANNA...MISSISSIPPI...ALABAMA AND THE FLORIDA PANHANDLE... ...SUMMARY... A tornado outbreak is possible on Saturday across the central Gulf Coast States and Deep South into the Tennessee Valley. Numerous significant tornadoes, and some long-track tornadoes are expected on Saturday afternoon and evening, centered on eastern Louisiana, Mississippi, and Alabama. Widespread damaging wind swaths and scattered large hail are likely. ...Tornado Outbreak Possible Across parts of the Southeast on Saturday... ...Gulf Coast States/Tennessee Valley/Southern Appalachians/Georgia... At mid-levels on Saturday, a strong and fast-moving jet streak will translate eastward across the southern U.S., as an associated trough moves through the Great Plains. Ahead of the system, a moist and unstable airmass will be in place across the lower to mid Mississippi Valley. Warming surface temperatures in the morning will contribute to the development of moderate instability across much of the moist airmass. As large-scale ascent increases ahead of the approaching jet streak, scattered thunderstorms are expected to initiate near the western edge of the moist airmass during the late morning, from eastern Louisiana into northwest Mississippi and western Tennessee. These storms should become severe rather quickly due large-scale forcing, moderate instability and strong deep-layer shear. Supercells with large hail, wind damage and a tornado threat are expected to develop and move east-northeastward during the afternoon across the central Gulf Coast States and Tennessee Valley. The exit region of the mid-level jet streak is forecast to move across the lower Mississippi Valley and Tennessee during the mid to late afternoon, which will be timed well with afternoon max heating. Forecast soundings at 21Z across parts of southern and central Mississippi have MLCAPE in the 2000 to 3500 J/kg range, with 0-6 km shear of 70 to 80 knots. 700-500 mb lapse rates are forecast to be near 8 C/km, with 0-3 km storm-relative helicity in the 400 to 500 m2/s2 range. This will be very favorable for intense severe storms, with a threat for tornadoes, wind damage and large hail. Several tornadic supercells are expected to develop within this cluster by mid to late afternoon as the low-level jet intensifies. Multiple long-track high-end tornadoes will be possible. The greatest tornado threat is expected to shift into Alabama by early to mid evening, with a significant tornado threat also impacting parts of middle Tennessee. In addition, supercells are expected to grow upscale into a developing MCS, with potential to produce significant severe wind gusts above 70 knots and large hail. The severe threat is expected to develop eastward into parts of Georgia and the southern Appalachians by mid to late evening. A severe threat should continue into the overnight. ...Ohio Valley/Lower Great Lakes... A negatively-tilted mid-level trough will move into the western Great Lakes on Saturday, as the southern part of the trough moves into the mid to upper Mississippi Valley. Ahead of the system, southwest mid-level flow will be in place over most of the Great Lakes and Ohio Valley. At the start of the period, a corridor of rich low-level moisture is forecast from western Kentucky northward into Indiana. Surface dewpoints along this corridor will likely range from the mid 50s to the lower 60s F. Early in the period, a cluster of strong thunderstorms is forecast to move across the Ohio valley. Some of the storms could have severe potential. Wind damage, isolated large hail and a few tornadoes will be possible. In the wake of this activity, outflow could negatively affect the airmass over parts of the Ohio Valley. However, areas that are not affected by outflow could re-destabilize, maintaining a severe threat. As the exit region of a mid-level jet moves across the Ohio Valley and lower Great Lakes during the late afternoon, supercells will be possible due to the increasing large-scale ascent and strong deep-layer shear. Any supercell could have potential for tornadoes, wind damage and hail. ..Broyles.. 03/14/2025 CLICK TO GET WUUS02 PTSDY2 PRODUCT NOTE: THE NEXT DAY 2 OUTLOOK IS SCHEDULED BY 1730Z
Category: Watches, Warnings, Advisories, & Hazards