Well, it appears fall is finally arriving to much of the continental US. A strong upper level low is slowly moving east across the northern US, dragging a strong cold front behind it. While it will not be a crushing winter storm like we recently saw in South Dakota, some snow is possible across the higher elevations of Colorado and Wyoming. Widespread overnight lows in 40s are expected behind the front, and it would not surprise me to see 20s in 30s in some areas, especially at higher elevations or at the more northern points. This chilly airmass will make it as far south as the Gulf Coast, leaving the lower elevations of Southern California and the Florida peninsula as the only places that will miss out on the cool down.
Elsewhere, everything appears quiet on both the tropical weather and severe weather fronts for the next week or so. Cool and dry air will preside over much of the lower 48, preventing thunderstorm formation. As the jet stream drops south for the winter, shear increases further south, and in this case, high shear levels (more than 20-30 knots) preside over the Caribbean, Gulf of Mexico, and much of the North Atlantic. These shear values are way too high to support tropical cyclone formation.