US Day 3-7 Hazards Outlook NWS Weather Prediction Center College Park MD 433 PM EDT Mon Aug 30 2021 Valid Thursday September 02 2021 - Monday September 06 2021 Hazards: - Heavy rain across much of Minnesota, Thu-Fri, Sep 2-Sep 3. - Heavy rain across southeastern New England, Thu, Sep 2. - Flooding possible across portions of the Northeast, the central Appalachians into the Mid-Atlantic, northeastern Mississippi, southern Alabama, and western Florida Panhandle. - Flooding occurring or imminent near and east of the lower Mississippi Valley, as well as portions of the upper Midwest. - Heavy rain across the eastern portion of the Kenai Peninsula, Thu-Fri, Sep 2-Sep 3. Detailed Summary: The medium range period (Thursday, Sep 2 to Monday, Sept 6) should begin with post-tropical cyclone Ida in the process of exiting the East Coast. There are still notable differences among deterministic models on how fast the system will move off the coast on Thursday. The more robust ECMWF solution maintains a higher degree of interaction between the circulation of Ida and an upper-level trough, allowing a stronger and slower-moving cyclone to track across the Mid-Atlantic states Thursday morning in contrast with the weaker and faster motion forecast by the GFS. A heavy rain axis is likely to extend north of the cyclone track. The heavy rain area shown on the map represents an intermediate solution somewhere between the ECMWF and the GFS. Meanwhile, a frontal system is forecast to move across the northern Plains during the latter portion of this week. It appears that heavy rainfall associated with organized thunderstorms will be most likely in the vicinity of Minnesota ahead of a frontal system's triple point. Elsewhere, there is an increasing chance of thunderstorms over Florida by this weekend into next Monday as the cold front extending southwest from extratropical Ida moves into northern Florida and becomes nearly stationary. Some of the thunderstorms may result in heavy rainfall but they are not expected to be widespread and organized. Elsewhere, some residual tropical moisture from former hurricane Nora could still bring some locally enhanced rainfall across the higher terrain of New Mexico Thursday and Friday. Over Alaska, an occluded cyclone edging closer to the southern coast should bring heavy rainfall mainly on the eastern portion of the Kenai Peninsula Peninsula and nearby areas just to the east on Thursday and into Friday. Some heavy rainfall could move into the southern end of the Alaska Panhandle but uncertainty is currently a bit too high for specifying a heavy rain area. Kong