US Day 3-7 Hazards Outlook
NWS Weather Prediction Center College Park MD
332 PM EDT Thu Jun 10 2021
 
Valid Sunday June 13 2021 - Thursday June 17 2021
 
Hazards:
- Flooding occurring or imminent across portions of the Lower Mississippi Valley, the Southern 
Plains, and the Tennessee Valley.
- Flooding likely across portions of the Tennessee Valley.
- Excessive heat across portions of the Central Great Basin, the Northern Rockies, the Central 
Rockies, California, the Northern Great Basin, and the Southwest, Sun-Thu, Jun 13-Jun 17.
- Excessive heat across portions of the Central Great Basin, California, and the Southwest, 
Wed-Thu, Jun 16-Jun 17.
- Excessive heat across portions of the Central Rockies, the Central Plains, the Upper Mississippi 
Valley, the Northern Plains, and the Northern Rockies, Sun-Wed, Jun 13-Jun 16.
- Much above normal temperatures across portions of the Central Plains, the Central Rockies, the 
Central Great Basin, the Northern Plains, the Northern Rockies, the Southern Rockies, the Middle 
Mississippi Valley, the Northern Great Basin, the Upper Mississippi Valley, the Great Lakes, and 
the Southwest, Sun-Thu, Jun 13-Jun 17.
 
Detailed Summary:

The medium range forecast period (Sunday, June 13 to Thursday, June 17) will feature a building 
upper-level ridge over the Southwest and central/southern Rockies, with upper-level troughs found 
over the East and Pacific Northwest. As a result, this weather pattern is forecast to focus much of 
the precipitation along the East Coast, Southeast, and Gulf Coast. However, outside of local 
impacts from isolated downpours, no widespread heavy rain is expected during this time frame. 
Temperatures are expected to remain around average to slightly below average along the East Coast, 
Southeast, and Deep South as well.

The main weather story across the Lower 48 during the medium range period will be associated with 
excessive heat and much above average temperatures throughout the West and north-central United 
States. By Sunday, above average temperatures will begin to build across the Intermountain West, 
northern/central Rockies, and northern Plains. The sizzling heat will settle over this region due 
to an anomalously strong upper-level ridge/high pressure centered near the Four Corners region. 
There is high confidence within the global forecast guidance regarding this feature and associated 
weather pattern. The center of the highest temperature anomalies (15 to 25 degrees above average) 
are currently forecast over the northern Rockies and northern High Plains on Monday and Tuesday of 
next week. Widespread temperatures in the 90s are expected, with triple digits also likely 
extending over central and eastern Montana into the northern Plains. The excessive heat area on the 
hazards graphic found over the Northern Plains highlights where the greatest chances of high 
temperatures eclipsing the century mark exist. This area of extreme heat may make it dangerous for 
residents spending an extended amount of time outdoors, or those that do not have access to air 
conditioning. The heat should relax a bit on Thursday from the Northern Rockies to the Upper 
Midwest, but remain around 10 degrees above average. The Intermountain West will also see scorching 
heat beginning on Sunday and lingering through next week. Places such as Salt Lake City, Utah could 
experience multiple days with high temperatures close to 100 degrees. Parts of the northern Great 
Basin should see a brief relief from the summer heat on Wednesday as a Pacific cold front sweeps 
through. Meanwhile, the Desert Southwest will also see its fair share of extreme and relentless 
heat, which will undoubtedly increase the already exceptional drought conditions over the region. 
With several consecutive days of high temperatures between 110 and 120 degrees possible beginning 
on Sunday, residents are urged to plan on spending plenty of time indoors/out of the heat. High 
temperatures will likely soar higher than 120 degrees throughout the typical desert valleys in the 
Southwest starting on Tuesday. This heat, along with the aforementioned upper-level high pressure 
system, is forecast to expand westward and into parts of California by Wednesday. Several daily 
high temperature records are forecast early next week from southwest California and Arizona to 
Montana. A few monthly and/or all-time temperature records are not out of the question throughout 
the Southwest as well. 

No widespread hazardous weather is expected for Alaska during this time frame.

Snell