US Day 3-7 Hazards Outlook
NWS Weather Prediction Center College Park MD
428 PM EDT Fri Aug 09 2019
 
Valid Monday August 12 2019 - Friday August 16 2019
 
Hazards:
- Heavy rain across portions of the Middle Mississippi Valley, the Great Lakes, the Upper 
Mississippi Valley, and the Northern Plains, Mon, Aug 12.
- Heavy rain across portions of the Southeast, Thu, Aug 15.
- Heavy rain across portions of the Great Lakes, the Central Appalachians, and the Ohio Valley, 
Tue, Aug 13.
- Flooding occurring or imminent across portions of the Central Plains, the Southern Plains, and 
the Northern Plains.
- Flooding likely across portions of the Central Plains, the Middle Mississippi Valley, and the 
Northern Plains.
- Excessive heat across portions of the Lower/Middle Mississippi Valley, the Tennessee/Ohio Valley, 
the Southeast, and the Southern Plains, Mon-Wed, Aug 12-Aug 14.
- Excessive heat across portions of Southern Texas, Mon-Fri, Aug 12-Aug 16.
- Excessive heat across portions of the Central Plains and the Middle Mississippi Valley, Mon, Aug 
12.
- Heavy rain across portions of interior Alaska, Tue-Wed, Aug 13-Aug 14.
- High winds across portions of the Aleutians, Wed-Thu, Aug 14-Aug 15.
- High significant wave heights for coastal portions of the Aleutians, Wed-Thu, Aug 14-Aug 15.
 
Detailed Summary:

Above normal temperatures will continue next week over a portion of the southern/southeastern 
states underneath an expansive upper high. Portions of eastern/southeastern Texas into the lower 
Mississippi Valley will continue to see highs in the 90s and low 100s with dew points in the upper 
60s in western areas to the upper 70s near the Mississippi River and Gulf Coast. This will combine 
to produce heat index values of 105-115F for the duration of the period over south Texas and for at 
least the first few days of the week over much of the rest of the area. Farther north, morning lows 
Mon/Tue may only be in the upper 70s to near 80F but a cold front should lower temperatures by late 
Tuesday and beyond. Areas of the Southeast east of the southern Appalachians will see a couple days 
of excessive heat as temperatures climb into the middle and upper 90s. Some areas may approach 
daily record highs and many areas may set new daily record high minimum temperatures.  

To the north, heavy rain will be possible Monday ahead of a system moving out of Montana and 
through the High Plains. Farther east, a cold front will slowly sink southward through the Midwest 
Monday/Tuesday with a warm/humid air mass to the south. As a wave of low pressure rides along the 
boundary, heavy rain will be possible both Monday/Tuesday from the Upper Midwest into Ohio/western 
Pennsylvania as the front progresses eastward and southward. 

Over Alaska, a weakening occlusion will push eastward as just a cold front across Southcentral as 
another cold front drops southward from the Brooks Range. This will squeeze moisture through the 
area which may be locally heavy. Uncertainty exists in how much moisture may funnel eastward out of 
the eastern Bering Sea but the ensemble signal is there for at least modest rain around Tuesday 
and/or Wednesday. Farther west, guidance still shows a fairly deep surface cyclone with its warm 
front approaching the western Aleutians next Wednesday and into the Bering Sea Thursday This will 
spread rain and high winds across parts of the island chain. Waves may near 20ft on the Pacific 
side per the ensemble probabilities generally west of Dutch Harbor. The system is forecast to lift 
northward through the western Bering Sea next Friday.

Fracasso