***Areas of heavy rainfall for the Southwestern U.S.***
***Late summer heatwave for the Dakotas and Upper Midwest***
***Pleasant weather for the East Coast***
For the rest of the weekend and into Monday, the region of the country
with the most active weather will be the Desert Southwest and into the
Great Basin. Moisture from Tropical Storm Ivo, combined with rich
monsoonal flow from Mexico, will result in numerous showers and
thunderstorms. Heavy rainfall and localized flooding appear to be the
main hazards, and orographically enhanced rainfall can be expected near mountain ranges.
Over the Northern Plains and Upper Midwest, heat will be making weather headlines. Local weather forecast offices in this region have already issued heat advisories and a few excessive heat warnings for high temperatures in the mid to upper 90s, and heat indices of 100-105 degrees. Overnight lows in the 70s will also be well above average for late August. This is the result of a building ridge of high pressure aloft.
Elsewhere, a high quality airmass will continue to deliver rather pleasant weather conditions for the Northeast and Mid-Atlantic through Sunday night, before warmer weather returns on Monday. Humidity levels will also be held in check during this time.
Farther south, scattered showers and storms will be possible along the Gulf Coast as a stationary front slowly dissipates over the region.