Weather across America

(NATIONAL) A heavy rainfall event unfolds across the southern Plains to the lower Mississippi Valley, rounds of strong thunderstorms expected to continue moving across the Ohio Valley and the Appalachians, and heat in the Northwest will spread east into the northern Plains as unsettled weather moves into the East Coast. 

A multi-day heavy rainfall event is in progress over parts of the southern Plains as an upper-level trough begins to direct the antecedent heavy rain across the Southwest eastward. Heavy rain will only progress relatively slowly east toward the lower Mississippi Valley over the next couple of days.  Additional rainfall of 3-6 inches with isolated pockets of 7+ inches are forecast to accumulate over the next 5 days from central Texas to central Mississippi. 

Much of this rainfall will be beneficial and welcome due to the effects of an ongoing drought, but the potential still exists for instances of flash flooding in urban areas and places with poor drainage. Slight Risks of Excessive Rainfall leading to Flash Flooding are in effect for portions of the southern Plains and lower Mississippi Valley through Tuesday, with a moderate risk and Flash Flood Watches in effect in parts of the ArkLaTex, northeastern Texas and nearby Oklahoma Sunday night.

Elsewhere, an upper-level low slowly moving eastward across the Midwest will continue to bring rounds of showers and thunderstorms, some of which may be severe with heavy downpours, across the Ohio Valley and into the Appalachians Sunday night. A Slight Risk of Severe Thunderstorms is in effect as a result. Much of this activity will spread into the eastern U.S. on Monday as a front begins to lift northward up the East Coast. The unsettled weather is forecast to persist into early on Tuesday as the upper low continues to take its time moving through the Northeast.

Temperatures are expected to drop well below average across the southern Plains and Lower Mississippi Valley due to clouds and rainfall forecast for that region over the next few days.  Meanwhile, the heat will continue across the Northwest and interior California but with a gradual moderating trend over the next couple of days. Some of the heat is forecast to spread eastward slowly across the northern Plains as a low pressure system lingers in the lee side of the northern Rockies.  

Over the Northeast, above normal temperatures across New England today will give way to increasing clouds, a chance of heavy rain and cooler temperatures over southern New England on Monday as a warm front approaches from the south.