Hydrologic Outlook

ESFGJTLow pressure begins to dig southward from the PACNW on Friday, tapping into a fetch of Pacific moisture that will evolve into an atmospheric river streaming into the Desert Southwest this weekend. Showers and thunderstorms develop on Friday and Saturday across the region. Lighter rainfall totals Friday and Saturday will reflect, initially lower, moisture. However, a few thunderstorms could produce impactful downpours on saturated soils left over from last weekend's historic rainfall.Deeper moisture develops Saturday night and early Sunday. This is expected to produce heavier and more widespread rainfall across southeast UT and southwest CO Sunday and Monday, mostly below 10000 feet. While rivers are forecast to remain below action stage, a growing concern lies in the potential for runoff around saturated hillsides in the region. This could produce rock, mud, and debris flows onto roadways, as well as flash flood prone burn scars, washes, slot canyons, and arroyos. Early estimates predict an area of 1 to 2 inches of new rainfall for portions of southeast UT and southwest CO.This is a preliminary forecast that hinges on slight shifts in a strong moisture plume impacting the region. It also attempts to capture the most statistically likely outcome, despite stronger and weaker outlier predictions. Outdoor enthusiasts, motorists, and residents of recent flood impacted areas are encouraged to remain abreast of the developing forecast in the coming days.