ACUS01 KWNS 041950 SWODY1 SPC AC 041948 Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0248 PM CDT Tue Aug 04 2026 Valid 042000Z - 051200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF SOUTHEAST ARIZONA... ...SUMMARY... Scattered severe wind gusts are possible across southeast Arizona during the late afternoon and evening. ...20Z Update... No major changes have been made to the outlook. Initial high-terrain storm development is expected to move west-southwestward across southeast AZ from late afternoon into the evening, with a primary threat of scattered severe gusts. Other strong to locally severe storms are possible through the afternoon into the early evening across parts of the Raton Mesa and south-central High Plains, parts of IA/northern MO, and the southern Appalachians/western Carolinas region. Late tonight, a few strong elevated storms may develop across parts of southeast NE, IA, and northern MO. See the previous discussion below for more information. ..Dean.. 08/04/2026 .PREV DISCUSSION... /ISSUED 1125 AM CDT Tue Aug 04 2026/ ...Southeast Arizona... A flattened mid/upper-level ridge over the Southwest will continue to feature a belt of modestly enhanced mid-level easterlies across northern Mexico into far southern portions of AZ/NM. Even with convective overturning yesterday, a seasonably moist low-level airmass across southeast AZ/southwest NM will undergo strong heating this afternoon, with up to 1000-2000 J/kg MLCAPE forecast per latest RAP/NAM forecast soundings. Initial widely scattered convective development over the higher terrain will gradually move westward across southeast AZ during the late afternoon and evening. A very well-mixed boundary layer with steep low/mid-level lapse rates ahead of this activity will support ample evaporative cooling potential with the stronger thunderstorm downdrafts. The resultant microbursts and associated outflow should yield a risk for 60-80 mph gusts as thunderstorms potentially congeal into one or more small clusters through the evening. ...Eastern Nebraska into Iowa and Northern Missouri... Elevated thunderstorms are ongoing late this morning across parts of NE to the north of a surface cold front extending from the southern High Plains northeastward to the Upper Midwest. Stronger mid-level flow and related large-scale ascent will tend to remain displaced to the north of the front through the period. But, there may still be some potential for a surface-based thunderstorm or two to develop along/near the front late this afternoon/early evening across IA/northern MO and vicinity in a moderately unstable airmass. While still appearing fairly conditional, isolated hail/damaging winds may occur if convection develops. Otherwise, a greater chance for additional elevated thunderstorms should exist tonight into early Wednesday morning from eastern NE into IA. This activity may also pose an isolated hail/gusty wind threat. ...Raton Mesa into the Southern/Central High Plains... Although overall magnitudes will remain limited, a local maximum in instability should develop this afternoon near the Raton Mesa into southeast CO, where widely scattered thunderstorms will likely develop in a post-frontal low-level upslope regime. Recent high-resolution guidance continues to show this activity moving slowly southeastward into parts of the OK/TX Panhandles during the early evening. While deep-layer shear is expected to remain modest (20-30 kt), marginally severe hail is possible with the stronger cores, and isolated severe gusts may occur with any loosely organized clusters that can develop. ...Southern Appalachians/Western Carolinas... A closed mid-level low will remain centered over GA today. To the east/northeast of this low, filtered daytime heating of a moist low-level airmass will support the development of moderate instability over the western Carolinas into north GA and eastern TN this afternoon. Scattered thunderstorms will continue to develop across this region through 17-19Z as convective temperatures are reached. Even though deep-layer shear will remain weak, an isolated threat for damaging winds associated with microbursts may develop as low-level lapse rates gradually steepen. $$