US Day 3-7 Hazards Outlook
NWS Weather Prediction Center College Park MD
355 PM EDT Wed May 26 2021
 
Valid Saturday May 29 2021 - Wednesday June 02 2021
 
Hazards:
- Heavy rain across portions of the Central/Southern Plains, and the Middle Mississippi Valley,  
Sat-Tue, May 29-Jun 1.
- Flooding possible across portions of the Central/Southern Plains, and the Middle Mississippi 
Valley.
- Flooding occurring or imminent across portions of the Central/Southern Plains, and the 
Middle/Lower Mississippi Valley.
- Flooding likely across portions of the Northern Rockies.
- Much above normal temperatures across portions of California, the Great Basin, the Pacific 
Northwest, and the Northern Rockies , Mon-Wed, May 31-Jun 2.
- Heavy rain across portions of the Alaska Panhandle and mainland Alaska, Sat-Sun, May 29-May 30.
 
Detailed Summary:

In the medium-range forecast period, which includes the Memorial Day weekend, a front extends from 
the Mid-Atlantic southwestward to the Central Gulf Coast into the Southern Plains.  An area of low 
pressure over the Mid-Atlantic will have stronger wind associated with the pressure gradient over 
the Great Lakes on Saturday, with Lake Erie having the high wind the longest.  The wind speed will 
not meet the criteria for an area of high wind.  As waves of low pressure move offshore on 
Saturday, the pressure gradient associated with the waves of low pressure will produce stronger 
wind off the Northeast and the northern Mid-Atlantic Coast on Saturday into Sunday. With the 
holiday weekend coming, boaters are encouraged to check with the local forecast office for any 
marine advisories.

A wave of low pressure along the tail end of the front mentioned above will move eastward from the 
Central High Plains over the Central/Southern Plains on Monday into Wednesday.   The system will 
produce an area of heavy rain is depicted over parts of the Central/Southern Plains on Saturday 
through Tuesday.    There is uncertainty if the heavy rain will continue over parts of the Southern 
Plains on Wednesday.  As a result, the heavy rain area was not continued into Wednesday.  However, 
there may be changes in the models with the placement of heavy rain over the region on Wednesday, 
which will be monitored to see if a change will be needed.  Furthermore, the GFS is producing heavy 
rain over the Northeast on Wednesday.  In contrast, the ECMWF model has less rain over the 
Northeast without the feature producing heavy rain over the Northeast.   The GFS was dismissed in 
this case. 

Upper-level ridging will develop over the Pacific Northwest into California on Sunday into 
Wednesday. The upper-level ridging will allow temperatures to get into the upper 80s to the middle 
90s over the Northwest and the 90s into the 100s over parts of California.  With this in mind, an 
area of much above normal temperatures is directed over Monday into Wednesday. 

Furthermore, high pressure over the Eastern Pacific and a heat trough over California will produce 
strong winds offshore and near the coast. Still, at this time, the wind speed is below the criteria 
for an area of high winds.  However, the situation will need to have an eye kept on the wind to see 
if the wind will meet the criteria later.  With the holiday weekend coming, boaters are encouraged 
to check with the local forecast office for any marine advisories.

For Alaska, an area of low pressure along the Aleutians will move into the Gulf of Alaska by 
Sunday. Moisture associated with the low will stream into the coastal regions producing heavy rain 
from parts of the Kenai Peninsula eastward to the Inside Passage on Saturday and Sunday.  At this 
time, the precipitation seems to be rain, but some of the higher peaks will still get snow. 

Ziegenfelder