US Day 3-7 Hazards Outlook
NWS Weather Prediction Center College Park MD
358 PM EDT Tue Jun 04 2019
 
Valid Friday June 07 2019 - Tuesday June 11 2019
 
Hazards:
- Heavy rain across portions of the Northeast, the Mid-Atlantic, the Central Appalachians, the 
Great Lakes, and the Ohio Valley, Tue, Jun 11.
- Heavy rain across portions of the Central/Southern Plains, Tue, Jun 11.
- Heavy rain across portions of the Central Plains, the Lower Mississippi Valley, the Central 
Appalachians, the Tennessee Valley, the Middle Mississippi Valley, the Mid-Atlantic, the Southern 
Appalachians, the Southeast, and the Ohio Valley, Fri-Tue, Jun 7-Jun 11.
- Flooding possible across portions of the Middle Mississippi Valley, the Great Lakes, and the Ohio 
Valley.
- Flooding occurring or imminent across portions of the Plains, the Mississippi Valley, the 
Central/Northern Great Basin, the Great Lakes, and the Ohio Valley.
- Flooding likely across portions of the Southern Rockies, the Central Great Basin, and the 
Southwest.
- Excessive heat across portions of the Southern Plains, Fri-Mon, Jun 7-Jun 10.
- Much above normal temperatures across portions of California, the Pacific Northwest, and the 
Northern Great Basin, Mon-Tue, Jun 10-Jun 11.
- Much below normal temperatures across portions of the Northern/Central Great Basin, the 
Northern/Central Plains, the Northern/Central Rockies, California, and the Pacific Northwest, 
Fri-Sat, Jun 7-Jun 8.
 
Detailed Summary:

The medium range is expected to begin with split upper-level flow on Friday, with an upper-level 
trough positioned in the Southern Plains, but with the main jet stream across the northern tier of 
the U.S. In the northern stream, an upper low will be centered over the Pacific Northwest on 
Friday, with ridging across the Upper Midwest. Both upper troughs will move eastward throughout the 
period. In the southern stream, ample tropical moisture is forecast to spread ahead of the low into 
the Mississippi Valley, Tennessee Valley, Southeast, and eventually into the Mid-Atlantic. Rain is 
expected to move out of the Mississippi Valley by Monday, but persist in the Southeast, Tennessee 
Valley, and Southern Appalachians into the middle of next week. Multi-day rainfall totals of 
several inches are expected there. Uncertainty remains with the potential phasing of the northern 
trough and the southern trough later in the period, which lowers confidence regarding rainfall 
amounts by Tuesday farther north into the Mid-Atlantic and Northeast, but enough of a signal exists 
in the guidance to introduce heavy rainfall as a hazard there. 

To the north and west, the upper trough initially located in the Pacific Northwest is forecast to 
track through the Northern Rockies and Northern Plains over the weekend. This trough will help 
cause below average temperatures (mainly cool high temperatures) throughout the Northwest, as well 
as precipitation on Friday and Saturday. In higher elevations, some snow is possible in higher 
elevations with the cold temperatures, but particularly heavy snow is not expected other than for 
the highest peaks. There is some potential for heavy rain to spread into the Upper Great Lakes 
region ahead of the trough by Monday, but confidence in rainfall amounts was uncertain at this 
time. The weather pattern in the West will change somewhat quickly by the beginning of next week, 
as upper-level ridging comes into the West Coast behind the trough. This ridging is expected to 
lead to above average temperatures in the West Coast states by Monday and especially Tuesday. 

Elsewhere, excessive heat is expected for southern to southeastern Texas as an upper high is 
located in Mexico, with heat indices over 105 and up to 115 in far southern Texas. By Tuesday, the 
potential for heavy rain may return to the Southern and Central Plains. Currently, the GFS/GEFS 
suite as well as the CMC indicate higher rainfall totals in this area compared to the ECMWF suite. 
However, the location of the forecast rain centered in the Texas/Oklahoma panhandles is similar in 
the EC, increasing forecast confidence in placement for a day 7 forecast, though there is 
considerable uncertainty in the magnitudes. 

No hazardous weather is anticipated for Alaska through the medium-range period.


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