US Day 3-7 Hazards Outlook
NWS Weather Prediction Center College Park MD
420 PM EDT Wed Jul 31 2019
 
Valid Saturday August 03 2019 - Wednesday August 07 2019
 
Hazards:
- Heavy rain across portions of the Middle/Lower Mississippi Valley and the Southern Plains, 
Sat-Sun, Aug 3-Aug 4.
- Flooding possible across portions of the Upper Mississippi Valley and the Northern Plains.
- Flooding occurring or imminent across portions of the Lower Mississippi Valley and the Northern 
Plains.
- Heavy rain across portions of mainland Alaska, Sat, Aug 3.
- High winds across portions of western mainland Alaska, Sat, Aug 3.
- High winds across portions of northern mainland Alaska, Sun, Aug 4.
 
Detailed Summary:

The upper-level pattern for the weekend and beyond is forecast to have fairly persistent ridging 
centered across the Four Corners region and troughing for the eastern U.S. In the northwest flow in 
between these features, heavy rain is expected to move into the Lower Mississippi Valley from the 
north over the weekend as moisture levels are high. Then east of the aforementioned trough, heavy 
rainfall is expected along a front in the western Atlantic. High moisture levels could combine with 
a tropical wave to create rainfall farther south into the Florida peninsula, which could be locally 
heavy over the weekend. Additionally, monsoonal moisture flowing into the Four Corners region could 
cause locally heavy rainfall and localized flooding and flash flooding as showers and thunderstorms 
increase there. As the overall pattern is pretty typical for the beginning of August, no 
significant temperature anomalies are expected through the period.

As an upper-level trough moves across northern Alaska this weekend, a couple of surface low 
pressure systems are expected to track across that region. There is potential for heavy rainfall to 
continue from the short range into Saturday for parts of mainland Alaska ahead of the frontal 
systems. Additionally, the relatively strong pressure gradient for this time of year could lead to 
high winds across western Alaska on Saturday and along the Arctic coast on Sunday.

Active weather is expected to ramp up over Hawaii as Hurricane Erick and then Hurricane Flossie 
approach. The National Hurricane Center currently has Erick passing south of the islands as a 
tropical storm on Friday and into the weekend. Hawaii itself, particularly the Big Island, could 
see heavy rain, gusty winds, and high surf even as Erick stays south. Then Flossie is expected to 
take a more northern track compared to Erick, and the current forecast has Flossie directly 
approaching the Big Island as a tropical storm by Monday. However, uncertainty remains regarding 
the track of the storm and therefore its impacts on Hawaii. 

Tate