1AM Day 3 Convective Outlook for Monday, July 14. THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE NORTHERN PLAINS
SUMMARY
Isolated strong to severe thunderstorms are possible across portions of the northern Plains Monday evening.
Discussion
Generally low-amplitude west/northwest flow will spread across the northern tier of the U.S. on Monday, confining any enhanced deep-layer flow to the north-central states. Elsewhere, a weak deep-layer flow regime will prevail within modest upper ridging across the Southeast and West. A weak upper low may persist over the southern Plains/Ozark Plateau vicinity.
A seasonally moist airmass with pockets of moderate instability will support scattered convection from the Plains to the Eastern Seaboard. However, lack of forcing and weak deep-layer flow will limit severe potential across much of the country. The exception may be across parts of the northern Plains.
A surface low is forecast to develop across the northern High Plains in response to weak height falls during the evening/overnight. A cold front will develop south across parts of the Dakotas while a surface trough extends south across the northern High Plains. These boundaries could become a focus for isolated thunderstorm development during the late afternoon/evening. Steep lapse rates, moderate instability and sufficient shear should support a few organized cells capable of producing strong/severe wind gusts and perhaps isolated hail.