McAllen Miller International, TX

Weather Underground midday recap for Sunday, May 26, 2013.

Unsettled weather developed in the nation's mid-section on Sunday, while severe storms became possible in the High Plains. Showers and thunderstorms developed from parts of the Northern Plains through the Mid-Mississippi Valley and into the western Ohio Valley during the morning and afternoon as low pressure from the West moved into the Central Plains and an associated warm front extended from the low through the Mid-Mississippi Valley and into the Southeast. Moisture from the Gulf of Mexico accompanied this warm front and supported convective activity from parts of the Northern Plains into the western Ohio Valley through the afternoon. Showers coupled with local runoff and possible heavy rains raised flood concerns in these areas, leading to Flood and Flash Flood Watches and Warnings issued for areas of southeastern South Dakota through central Iowa and into northwestern Illinois.

Meanwhile, increased instability over parts of the Northern High Plains into the Central Plains led to a slight risk of severe thunderstorm development from Sunday afternoon through Sunday night. While large hail was the primary severe weather threat for this region, a few tornadoes were still possible. A slight risk of severe weather was also possible in the Southern Plains, ahead of an associated dryline through the afternoon and evening. Damaging wind gusts and large hail were the primary hazards with these storms.

Elsewhere, a cold trough of low pressure remained over the Northeast on Sunday. This slow moving system supported more showers in the northern Northeast and led to below normal daytime highs. Persistent showers in the region led to Flood Advisories and Warnings from northern Maine through parts of northern Vermont. Out West, a trough of low pressure moved over the Pacific Northwest with scattered showers. Moisture from this system reached into parts of northern California and northern Nevada and kicked up a few light rain showers in the areas Sunday afternoon.