US Day 3-7 Hazards Outlook
NWS Weather Prediction Center College Park MD
324 PM EDT Wed Aug 28 2019
 
Valid Saturday August 31 2019 - Wednesday September 04 2019
 
Hazards:
- Heavy rain across portions of the Central Plains to the Middle Mississippi Valley, Sat, Aug 31.
- Heavy rain across portions of Florida and the Southeast, Sat-Wed, Aug 31-Sep 4.
- Flooding possible across portions of the Central Plains.
- Flooding occurring or imminent across portions of the Central Plains and the Northern Plains.
- Excessive heat across portions of the Southwest, Sat, Aug 31.
- High winds across portions of the Southeast, Sun-Wed, Sep 1-Sep 4.
- High significant wave heights for coastal portions of the Southeast, Sun-Wed, Sep 1-Sep 4.
- Heavy rain across portions of mainland Alaska and the Aleutians, Sat-Mon, Aug 31-Sep 2.
- High winds across portions of mainland Alaska and the Aleutians, Sat-Sun, Aug 31-Sep 1.
 
Detailed Summary:

A stationary frontal boundary to start the medium range period (Saturday) will continue to provide 
a focus for an area of showers and thunderstorms across portions of the Central Plains into the 
Middle Mississippi Valley. Multi-day rainfall totals of a couple of inches appear possible at this 
point from the end of the short range period and extending into Saturday. Even though much of this 
begins in the short range period, a heavy rainfall area was highlighted on the hazards map from 
roughly eastern Kansas into west-central Missouri for Saturday, Aug 31. 

In the Southwest, excessive heat late this week may continue into Saturday from the lower deserts 
along the Colorado River into the Phoenix/Tucson areas. Temperatures are expected to reach into the 
110s which may approach record highs in some locations. Temperatures should moderate by early next 
week as the upper ridge axis shifts eastward and an upper shortwave drops into the Pacific 
Northwest.

Confidence is increasing that Hurricane Dorian may be a major threat during the medium range for 
parts of Florida and the Southeast U.S.. The latest advisory from the National Hurricane Center 
takes Dorian into the Florida Space Coast Monday morning as a major hurricane. This would increase 
the chance for high winds, heavy rainfall, and significant waves to impact much of the Florida 
peninsula by the end of the holiday weekend, with the possibility of tropical related impacts 
extending northward into the Southeast early next week. There continues to be high uncertainty 
regarding the exact track of Dorian and so the current highlighted areas are likely to be refined 
in the coming days. Please refer to the National Hurricane Center (www.nhc.noaa.gov) for the latest 
information on Dorian.

In Alaska, a significant occluded cyclone is expected to bring heavy rain into the central/eastern 
Aleutians this weekend then eastward along coastal sections of southern Alaska into early next 
week. Also, southwestern Alaska from Bristol Bay to the Kuskokwim River may see heavy rain as the 
triple point lifts northeastward. Some strong winds are also possible through the Aleutians into 
southern coastal Alaska.

Santorelli