Severe Storm Outlook Narrative (AC)
Issued by NWS
Issued by NWS
266 ACUS48 KWNS 300900 SWOD48 SPC AC 300859 Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0359 AM CDT Sun Jun 30 2024 Valid 031200Z - 081200Z ...DISCUSSION... ...Day 4/Wednesday... At least some severe-weather potential will likely exist across parts of the Midwest and south-central Plains within the moist/unstable environment ahead of the advancing cold front and reinforcing outflows. This severe potential could include a corridor from Ohio/Indiana/Illinois southwestward across the Ozarks into Kansas and northern Oklahoma. Deep-layer shear atop the warm sector will likely be weaker as compared to prior days. Additional severe storms may occur near/north of the synoptic front across the north-central High Plains. Risk-magnitude uncertainties still preclude 15+ percent severe-weather probability delineations for these scenarios. ...Day 5/Thursday Midwest including Iowa/Missouri... Guidance is in relatively good agreement that a shortwave trough, and strong jet in its base, will overspread the north-central Great Plains toward the Upper Midwest on Thursday. Ahead of this mid/upper-level trough, very favorable ingredients, including ample instability and rather strong deep-layer shear for the season, may set up across the southern half of Iowa, northern half of Missouri, and possibly nearby parts of southeast Nebraska/northeast Kansas and western Illinois. However, the potential impacts of convection Wednesday night remain a key uncertainty regionally, and will thus defer to future outlooks for an introduction of 15+ percent severe probabilities. ...Days 6-8 Friday-Sunday... Predictability diminishes into this time frame, although corridors of at least some severe storms can be expected daily, generally spanning the northern/central Plains to the Ohio Valley and potentially parts of the East. For instance, on Day 6/Friday, related to the east-northeastward progression of the upper trough, an area of interest includes parts of the Ohio Valley toward the Lake Erie vicinity. ..Guyer.. 06/30/2024