US Day 3-7 Hazards Outlook
NWS Weather Prediction Center College Park MD
346 PM EDT Wed May 22 2019
 
Valid Saturday May 25 2019 - Wednesday May 29 2019
 
Hazards:
- Heavy rain across portions of the Plains, the Mississippi Valley, and the Great Lakes, Sat-Wed, 
May 25-May 29.
- Severe weather across portions of the Central Plains, the Northeast, the Central Appalachians, 
the Middle Mississippi Valley, the Mid-Atlantic, the Great Lakes, and the Ohio Valley, Sat, May 25.
- Flooding possible across portions of the Northern/Central Plains, the Northern Great Basin, the 
Upper/Middle Mississippi Valley, the Great Lakes, and the Ohio Valley.
- Flooding occurring or imminent across portions of the Plains, the Mississippi Valley, the Great 
Lakes, and the Ohio Valley.
- Flooding likely across portions of the Northern/Central Plains and the Upper/Middle Mississippi 
Valley.
- Excessive heat across portions of the Southern Plains, Tue-Wed, May 28-May 29.
- Excessive heat across portions of the Southeast, the Mid-Atlantic, the Lower Mississippi Valley, 
the Southern Appalachians, and the Tennessee Valley, Sat-Wed, May 25-May 29.
- Heavy precipitation across portions of mainland Alaska, Sat-Tue, May 25-May 28.
 
Detailed Summary:

A front extending from the Upper Great Lakes roughly southwestward to the Southern High Plains, on 
Saturday, will move eastward to the Northeast by Sunday while becoming quasi-stationary from the 
Ohio Valley to the Central High Plains. Moisture from the Gulf of Mexico will pool along the 
boundary and lift associated with the front will aid in making the air mass unstable producing 
severe thunderstorms along and ahead of the boundary over parts of the Central Plains,Middle 
Mississippi Valley, and the Ohio Valley/Lower Great Lakes into parts of the Northeast on Saturday. 
In addition, the moisture pooling a long the front and upper-level dynamics will aid in producing 
an area of heavy rain over parts of the Plains and Upper/Middle Mississippi Valley into parts of 
the Upper Great Lakes on Saturday through Wednesday. The heavy rain will be over different areas in 
particular from day to day but generally over the same region taken as a whole.  First the heavy 
rain will develop over parts of the Central Plains on Saturday into Sunday morning. As the front 
becomes quasi-stationary and more east-west oriented, on Sunday, the heavy rain will develop over 
parts of the Central Plains into the Middle Mississippi Valley on Sunday into Monday morning.  On 
Monday into overnight Monday, the axis of heavy rain will move northward to the Central High Plains 
eastward to the Middle Mississippi Valley.  On Tuesday into Wednesday morning, the heavy rain will 
be limited to parts of the Upper Mississippi Valley/Upper Great Lakes and over parts of Eastern 
Oklahoma into Northwestern Arkansas.  For Wednesday into Wednesday night the area of heavy rain is 
too uncertain to narrow down to one area.  

Upper-level ridging over the Southern Plains eastward to parts of the Southern 
Mid-Atlantic/Southeast and with maximum temperature anomalies in a range from +10 to +15 degree 
range will aid in producing an area of excessive heat over parts of the Southern 
Mid-Atlantic/Southeast into the Eastern Gulf Coast/Tennessee Valley Saturday into Wednesday. There 
will also be an area of excessive heat over parts of the Lower Rio Grande Valley from Tuesday into 
Wednesday. For simplicity purposes, the hazards outlook area for excessive heat focuses across the 
Southeast where these types of temperatures would be the highest experienced thus far this year.

Low pressure near the Aleutians, on Saturday, will move into the Bering Sea by Sunday. The 
associated front will move along the Southern Mainland Alaska Coast to near Yakutat by Monday as 
another area of low pressure moves near the Aleutians by Tuesday into Wednesday. A plume of 
moisture extending from near Hawaii into parts of the Aleutians, on Saturday, will also move 
eastward along the Mainland Alaska Coast to near Yakutat by Monday then dissipating. An area of 
heavy precipitation will develop over the area on Saturday from the South Mainland Alaska Coast 
that will slowly move eastward to near Yakutat by Tuesday.

Ziegenfelder