US Day 3-7 Hazards Outlook
NWS Weather Prediction Center College Park MD
358 PM EDT Tue Aug 31 2021
 
Valid Friday September 03 2021 - Tuesday September 07 2021
 
Hazards:
- Flooding possible across portions of the Northeast, the Central Appalachians, the Tennessee 
Valley, the Mid-Atlantic, the Southern Appalachians, the Southeast, the Great Lakes, and the Ohio 
Valley.
- Flooding occurring or imminent across portions of the Lower Mississippi Valley, the Tennessee 
Valley, the Middle Mississippi Valley, the Upper Mississippi Valley, the Southeast, and the Great 
Lakes.
- Heavy rain across portions of mainland Alaska, Fri, Sep 3.
 
Detailed Summary:

The medium range period (Friday, Sep 3 to Tuesday, Sept 7) will begin with flash flooding potential 
across the Northeast due to heavy rain from Ida. A heavy rain area wasn't added because the threat 
has now moved into the short range period. That being said, flooding remains a possibility into the 
medium range for parts of the Mid-Atlantic, Ohio Valley and Northeast. Waves of low pressure riding 
along an upper-level trough will bring rain to the Midwest over the medium range period. The Friday 
and Tuesday systems don't seem strong enough at this time to exceed our heavy rain threshold. A 
heavy rain threat exists along a thermal boundary over the Central Plains and Middle Mississippi 
Valley next Tuesday as potential convection may lead to elevated rain amounts. We'll monitor this 
moving forward.

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.

Kebede/Kong