Daily briefing: Touches of spring, summer

The changeover from spring to summer has been a roller coaster across the U.S., and this topsy-turvy trend continues today. Today's Daily Briefing, published every weekday promptly at 5 a.m. ET, provides all of the details, including the latest in the tropics.

A nearly stationary front slowly trudging its way across the central U.S. will be the dividing line between summer-like heat and a bit of a spring chill.

The WeatherRadar shows the front producing rain showers and a few thunderstorms from Texas to the Great Lakes, with soaking rain and thunderstorms across the Ohio Valley and eastern Great Lakes later today. The Texas thunderstorms could become severe too, especially ones that develop in the afternoon and evening.

East of the front, the Northeast and Mid-Atlantic will feel like mid-summer. Today's highs on the TemperatureRadar shows upper 80s in Boston and Philadelphia, with New York hitting the low 90s. Behind the front, mid-70s will keep the springlike feel in Chicago, Milwaukee, Minneapolis and throughout the central and northern Plains into the northern and central Rockies. A few spring showers and thunderstorms will be possible across the Plains and Rockies later in the day.

The roller coaster ride continues in the Southeast and Florida. Afternoon storms will bring localized flood threat as a weak storm system takes shape. The Tropical Update below has more details on this rainmaker.

Finally, the West will see afternoon thunderstorms throughout the Great Basin and Southwest while the Pacific Coast and California remains quiet. Temps will be in the 80s across the interior while the immediate coast will be in the 60s as coastal clouds linger.

All week, there has been a risk of a tropical or hybrid subtropical system developing off the Southeast Coast. The threat of offshore development has diminished but heavy rain and thunderstorms remain a threat throughout the Southeast and coastal Carolina. Localized flooding will be possible and beach plans will be washouts.

Otherwise, the tropics remain quiet.