SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1045 AM CST Mon Nov 10 2025 Valid 111200Z - 121200Z ...NO THUNDERSTORM AREAS FORECAST... ...SUMMARY... The risk for thunderstorms appears negligible across the U.S. Tuesday through Tuesday night. ...Discussion... A seasonably cold, dry boundary-layer air mass has spread as far south and east as much of the northwestern Gulf Basin and middle through southern Atlantic Seaboard, with cyclogenesis underway near the northern Mid Atlantic coast and forecast to proceed north-northeastward across portions of New England into the lower St. Lawrence Valley later today through tonight. By 12Z Tuesday, the occluding center of the cyclone is forecast to reach southeastern Quebec, before drifting northward and weakening as secondary cyclogenesis takes place across the Canadian Maritimes, in response to a vigorous short wave impulse accelerating northeastward near/offshore of the Atlantic Seaboard. While models indicate that large-scale mid/upper troughing will lose amplitude across the eastern U.S. in the wake of this feature, a digging upstream perturbation is forecast to maintain broadly cyclonic northwesterly mid/upper flow across the Great Lakes, and upper Mississippi through Ohio Valleys, downstream of building ridging inland of the Pacific coast through the Rockies and adjacent Great Plains. Beneath this regime, down slope flow and warm advection across much of the Great Plains, and continuing advection across and east of the Mississippi Valley, will likely contribute to significant boundary-layer modification. However, with only slow weakening of lingering surface ridging across the Gulf Basin and Florida Peninsula, little appreciable inland moisture return is anticipated. Generally stable conditions are likely to be maintained across much of the U.S., with little risk for thunderstorms. ...Lee of lower Great Lakes... Beneath the cold, cyclonic flow across the lower Great Lakes region, both the NAM and Rapid Refresh suggest that a plume of relatively stronger boundary-layer destabilization and deeper convective development is possible across and east-southeast of the eastern shores of Lake Erie late tonight through Tuesday afternoon. While equilibrium levels appear rather low, it is not entirely clear from forecast soundings that the development of charge separation is not possible. However, the potential for convection becoming more than briefly capable of producing a lightning strike or two still appears too low and/or isolated to introduce 10 percent or greater thunderstorm probabilities. ..Kerr.. 11/10/2025
