US Day 3-7 Hazards Outlook
NWS Weather Prediction Center College Park MD
412 PM EDT Wed Jul 17 2019
 
Valid Saturday July 20 2019 - Wednesday July 24 2019
 
Hazards:
- Heavy rain across portions of the Central Plains, the Central Rockies, the Central Great Basin, 
the Southern Rockies, the Southern Plains, and the Southwest, Sun-Tue, Jul 21-Jul 23.
- Heavy rain across portions of the Mid-Atlantic, the Lower Mississippi Valley, the Central 
Appalachians, the Tennessee Valley, the Northeast, the Southern Appalachians, the Southeast, the 
Southern Plains, and the Ohio Valley, Mon-Tue, Jul 22-Jul 23.
- Heavy rain across portions of the Middle Mississippi Valley, the Great Lakes, the Upper 
Mississippi Valley, and the Northern Plains, Sat-Sun, Jul 20-Jul 21.
- Heavy rain across portions of the Southeast and the Mid-Atlantic, Wed, Jul 24.
- Flooding occurring or imminent across portions of the Central Plains, the Lower Mississippi 
Valley, the Upper Mississippi Valley, 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 Mississippi Valley, the Central Appalachians, the 
Tennessee Valley, the Middle Mississippi Valley, the Upper Mississippi Valley, the Great Lakes, and 
the Ohio Valley, Sat, Jul 20.
- Excessive heat across portions of the Southeast, the Mid-Atlantic, the Northeast, and the Central 
Appalachians, Sat-Sun, Jul 20-Jul 21.
 
Detailed Summary:

A broad upper level ridge will encompass much of the central and eastern U.S. for the end of the 
work week and into the weekend, with the main storm track confined from the northern Rockies to the 
northern Great Lakes. Given the upper level pattern, cold fronts are not expected to make much 
progress south of 40 degrees north. This will allow for heat and humidity to build across the 
central plains to the Ohio Valley by the end of the week, and a second area of excessive heat for 
the East Coast region from Georgia to southern New England. Widespread high temperatures in the mid 
90s to low 100s can be expected for multiple days. In addition, dewpoints rising well into the 70s 
will result in heat indices reaching or exceeding 105 degrees, with some peaking in the 110 to 115 
degree range during peak afternoon heating. Another factor worth noting will be the anomalously 
warm overnight low temperatures. This will especially hold true for the big cities of the 
Mid-Atlantic and Northeast, with lows failing to fall below 80 degrees Friday night and Saturday 
night. This is assuming that no significant rainfall occurs during those evening and overnight 
periods. Heat-related weather headlines are either already posted, or will likely be posted, for 
both of the regions delineated on the hazards chart later in the week and the weekend.

The main area of concern for heavy rain will be across the Upper Midwest over the upcoming weekend, 
with the greatest potential on Sunday. There will likely be an organized thunderstorm complex in 
association with a developing surface low that will track on the northern periphery of the ridge. 
Total rainfall amounts on the order of 1 to 2 inches will be possible, but uncertainty remains on 
the exact placement across Minnesota and Wisconsin. There will likely also be patchy areas of heavy 
rain across the Southeast U.S. early next week, and also across parts of southern Colorado and 
northern New Mexico.

No weather hazards are forecast for Alaska during this period.


Hamrick