Severe Storm Outlook Narrative (AC)
Issued by NWS
Issued by NWS
718 ACUS48 KWNS 120827 SWOD48 SPC AC 120825 Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0325 AM CDT Mon Oct 12 2026 Valid 151200Z - 201200Z ...DISCUSSION... A short-wave trough over central Canada on Day 4/Thursday morning is forecast to undergo considerable amplification while progressing southeast through the Great Lakes to the Atlantic Coast by Day 5/Friday. That upper-air system will be attended by a surface low, which is expected to develop along a front from the mid-MS Valley through the OH Valley to off the New England coast. Meanwhile, a strong cold front will surge south, reaching the Gulf Coast by Friday night or early Saturday. In its wake, a drier, continental- polar airmass will overspread much of the CONUS east of the Rockies, limiting the threat for severe thunderstorms this weekend into early next week. ...Day 4/Thursday and Thursday night... Despite the potential for early-day showers and thunderstorms, a seasonably moist boundary layer is forecast along and to the south of the front and surface low in the mid-MS and OH Valleys. The moisture combined with daytime heating will contribute to at least modest air mass destabilization by afternoon. Both vertical shear and forcing for ascent will strengthen through the period with the approach of the midlevel trough. As such, some severe weather appears possible on Thursday with the threat possibly continuing through Thursday night from the OH Valley into the Mid-Atlantic. At least level-1/Marginal Risk probabilities may be required in the subsequent Day 3 Outlook for this time period. ...Day 5/Friday... As mentioned above, some severe weather threat could develop over the Mid-Atlantic late Thursday night or Friday morning with additional strong to severe storms possible by afternoon along the front in the southern Mid-Atlantic or Carolinas. ...Days 6 to 8/Saturday to Monday... No severe weather is currently expected. ..Mead.. 10/12/2026