Fig. 1-4: Severe thunderstorms across the western Great Plains today, a rainstorm in the Mid-south tomorrow, heavy rain for the Northeast FRI/SAT, and a big cooldown in the East next Sunday. Discussion: A late season severe thunderstorm outbreak is forecast for today across most of the western Great Plains to western Texas (Fig. 1). The severe weather loses strength tomorrow (except Texas) while dynamics to cause a heavy rainstorm convenes over Northeast Texas to Western Arkansas where 2-5 in. could occur featuring some flash flooding (Fig. 2). By FRI/SAT the rainstorm shifts into the Northeast U.S. and Quebec bringing 1-3 in. of rain (Fig. 3). After the rainstorm in the Northeast departs Sunday, a sprawling much cooler autumnal air mass spreads across the eastern half of the U.S. for Sunday (Fig. 4).