Forecast Discussion
191 FXUS64 KMEG 261827 AFDMEG Area Forecast Discussion National Weather Service Memphis TN 127 PM CDT Sun Apr 26 2026 ...New DISCUSSION, AVIATION, FIRE WEATHER... .KEY MESSAGES... Issued at 127 PM CDT Sun Apr 26 2026 - A medium chance for severe storms exists late Monday evening through early Tuesday morning. A Slight (level 2/5) Risk to Enhanced (level 3/5) Risk for damaging winds, hail, and a few tornadoes covers much of the Mid-South. - A second round of severe weather is expected late Tuesday evening into early Wednesday morning where a Slight (2/5) Risk is in effect across the entire Mid-South. - Weather will cool off and dry out through the end of next week with highs returning to the 70s and low 80s as early as Wednesday. && .DISCUSSION... (This evening through next Saturday) Issued at 127 PM CDT Sun Apr 26 2026 Late morning surface analysis showed a quasi-stationary boundary from the Red River Valley in Texas and Oklahoma to central Mississippi and Alabama. Mostly sunny skies have prevailed across the Mid-South with GOES Visible satellite trends showing a gradual increase in mid to high clouds over the Lower Mississippi Valley. Early afternoon temperatures are mainly in the lower 80s. Severe thunderstorm potential remains the predominant concern for Monday night and late Tuesday afternoon into Tuesday night. Upper-level ridging will bring rain-free conditions to the Mid- South this afternoon with highs mainly in the lower 80s. A mid- level shortwave trough over the Southwest U.S. will eject into portions of the Central and Southern Plains tonight. Meanwhile, a surface low will develop over the Central Plains tonight and will result in the nearby quasi-stationary boundary lifting back as a warm front tonight into Monday morning over the Lower Mississippi Valley. Short-term CAMs only indicate low coverage (20-30%) at best for any showers and thunderstorms as the front passes through the Mid-South. A very humid airmass will arrive in wake of the warm front with lower 70 degree dewpoints overspreading the area. Rain chances will remain minimal at best through at least mid afternoon on Monday as weak shortwave ridging builds in across the area. The very humid airmass combined with daytime heating will allow moderate to strong instability to develop across the Lower Mississippi Valley with surface-based CAPE values rising to 1500- 2500 J/kg by late Monday afternoon. A tightening pressure gradient associated with the surface low deepening and moving into the Upper Midwest and the development of a low-level jet will result in sustained winds reaching or exceeding 25 mph over portions of northeast Arkansas and the Missouri Bootheel late Monday morning into Monday afternoon. Probabilities from the NBM/HREF indicate a medium chance (50-70%) of sustained winds reaching or exceeding 25 mph, and numerical deterministic model guidance support the issuance of a Wind Advisory from 11 AM Monday through 6 PM Tuesday. A volatile pre-convective environment will develop across the region Monday evening as a 120 kt upper-level jet streak produces favorable upper level divergence over the area. Favorable parameters including steepening mid-level lapse rates, 0-6 km shear increasing 45-50 kts, and 0-1km storm relative helicity values rising up to 300 m2/s2 and short-term model sounding hodographs showing favorable curvature suggest convective initiation will be most likely in the form of supercells. Short term model trends including CAMs suggest the most likely time for strong to severe thunderstorms to occur across the Mid-South will be mainly from mid-evening into early Tuesday morning. However, models do present some uncertainty on whether a pre-frontal trough will exist to produce any convective activity ahead of the front along with convective activity becoming quasi-linear by early Tuesday morning. Large hail, damaging winds, and tornadoes are the severe weather threats with this first round of severe weather. A secondary shortwave trough is expected to move into the Middle and Lower Mississippi Valleys by Tuesday night. This shortwave combined with the redevelopment of moderate to strong instability and shear is likely to result in a second round of strong to severe thunderstorms producing all hazards across the Mid-South late Tuesday afternoon into early Wednesday morning as a cold front moves through the area. Mid to long range model trends indicate high pressure will bring a short period of dry weather for the second half of Wednesday followed by a return of rain chances Thursday into Friday as a shortwave trough embedded within northwest flow aloft moves through the Mid-South. && .AVIATION... (18Z TAFS) Issued at 127 PM CDT Sun Apr 26 2026 VFR conditions will prevail over the next 30 hours. East/southeast winds will remain light through the remainder of today. Winds will shift south/southeast beginning around 09Z tomorrow with gusts, up to 30kts, beginning around 15Z across all terminals. There is a very low (