US Day 3-7 Hazards Outlook
NWS Weather Prediction Center College Park MD
358 PM EDT Thu May 27 2021
 
Valid Sunday May 30 2021 - Thursday June 03 2021
 
Hazards:
- Heavy rain across portions of the Southern Rockies, and the Central/Southern Plains, Sun-Mon, May 
30-May 31.
- Flooding possible across portions of the Middle Mississippi Valley, and the Central/Southern 
Plains.
- Flooding occurring or imminent across portions of the Middle/Lower Mississippi Valley, the 
Central/Southern Plains, and the Northern Rockies.
- Flooding likely across portions of the Central Plains.
- Much above normal temperatures across portions of California, the  Great Basin, the Pacific 
Northwest, and the Northern Rockies, Mon-Thu, May 31-Jun 3.
- Heavy rain across portions of the Alaska Panhandle and mainland Alaska, Sun-Tue, May 30-Jun 1.
 
Detailed Summary:

In the medium-range forecast period, which includes the Memorial Day weekend, a front extends from 
the Mid-Atlantic southwestward to the Gulf of Mexico into the Southern Plains. An area of low 
pressure over the Mid-Atlantic and just offshore will have stronger wind associated with the 
pressure gradient on Sunday into very early on Monday morning.  The wind speed will not meet the 
criteria for an area of high wind.  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 Tuesday.   The system will 
produce an area of heavy rain over parts of the Central/Southern Plains on Sunday through Monday.   
 The low pressure will move northeastward into the Middle Mississippi Valley/Western Ohio Valley on 
Wednesday and Thursday with a trailing front over the Lower Mississippi Valley into the Southern 
Plains. There is uncertainty if heavy rain will develop over parts of the Lower Mississippi Valley 
regarding rainfall amounts and areal coverage on Thursday.  As a result, the heavy rain area was 
not placed on Thursday. 

Upper-level ridging will develop over the Pacific Northwest into California on Sunday into 
Thursday. The upper-level ridging will allow temperatures to get into the upper 80s to the middle 
90s over the Northwest/Great Basin and the 90s into the 100s over parts of California.  With this 
in mind, much above normal temperatures are depicted over the region from Monday into Thursday. 

Furthermore, high pressure over the Eastern Pacific and a heat trough over California will produce 
strong winds offshore and near the coast on Sunday into Wednesday morning. 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 on 
Sunday. Moisture associated with the low will stream into the coastal regions producing heavy rain 
from parts of the Kenai Peninsula eastward to near Valdez on Sunday.  On Monday, heavy rain will 
fall on the Pacific side of Kodiak Island and the Alaska Peninsula Coast across from Kodiak Island. 
 On Tuesday, the heavy rain moves towards Yakutat. 

Ziegenfelder