There was a high chance of this system becoming a tropical cyclone as it trekked northwestward at 5 to 10 mph throughout the day. Regardless of further development, heavy rainfall was expected along the western Gulf Coast. This area was encouraged to monitor the development and progression of this system throughout the day.
Elsewhere, in the South, wet weather would continue throughout the northern Florida Peninsula as a stationary frontal boundary near the state line maintained scattered showers and thunderstorms. Easterly winds associated with high pressure building down the Eastern Seaboard would enhance thunderstorm activity throughout the day.
In the North, a strong low pressure trough would move eastward across the Upper Midwest with significant weather activity. The Labor Day storm would spread significant precipitation and thunderstorms from the Northern Rockies and Northern Plains into the Upper Mississippi Valley. While the heaviest amounts of precipitation would affect North Dakota, Minnesota should expect the strongest thunderstorm activity. Storms in this state might turn severe with damaging winds, hail and isolated tornadoes. Along with unsettled weather, cooler temperatures were expected with the passing of this system.
Calmer weather activity was expected throughout the rest of the nation the Labor Day.
Temperatures in the Lower 48 states Sunday ranged from a low of 25 degrees at Ukiah, Ore., to a high of 115 degrees at Death Valley, Calif.