US Day 3-7 Hazards Outlook
NWS Weather Prediction Center College Park MD
359 PM EDT Wed Mar 27 2019
 
Valid Saturday March 30 2019 - Wednesday April 03 2019
 
Hazards:
- Heavy precipitation across portions of the Pacific Northwest, Mon, Apr 1.
- Heavy rain across portions of California and the Pacific Northwest, Mon, Apr 1.
- Heavy rain across portions of the Midwest, Wed, Apr 3.
- Flooding possible across portions of the Missouri River Basin.
- Flooding occurring or imminent across portions of the Mississippi and Missouri River Basins.
- Flooding likely across portions of the Mississippi and Missouri River Basins.
 
Detailed Summary:

The medium range hazards period (Saturday, March 30 - Wednesday, April 3) begins with an exiting 
low pressure system and trailing cold front tracking through the south-central and eastern U.S.. 
While moderate rainfall is likely along the front, a widespread heavy rainfall threat is not 
anticipated given the front should be fairly progressive in nature. Snow accumulations are also 
possible from the Great Lakes to interior/northern New England, but appear at this point to be 
below hazard criteria. The southern portion of this boundary will linger into next week across 
Florida and the Gulf of Mexico, with models indicating the potential for a surface low to develop 
along the front, tracking across Florida and off the East coast. This may pose a threat for 
enhanced rainfall across parts of Florida and the Southeast/Mid-Atlantic coast, but uncertainty is 
still high on the track and intensity of this system so a heavy rainfall hazard was not introduced.

Another trough moving into the Pacific Northwest may bring a period of moderate to heavy 
precipitation to portions of the region on Monday, April 1. Liquid equivalent amounts of 1-2 inches 
are possible, with the heaviest totals mainly confined along and west of the Cascades. Temperatures 
should be warm enough to support mostly rain, with the exception of the highest elevations of the 
Washington and Oregon Cascades. As this system moves east into the Interior West, there is the 
potential for accumulating snowfall across parts of the Rockies, but at this point amounts do not 
look overly impressive and should remain below hazard criteria.

Moderate to major flooding across the Mississippi and Missouri River Basins is expected to continue 
through the forecast period, especially considering the potential for heavy rainfall across this 
region at the end of this week (just before the hazards period begins). Another system moving into 
the region by next Wednesday may bring another round of heavy rainfall, but there is high 
uncertainty on timing and rainfall amounts at this point in time. Despite the uncertainty though, a 
heavy rainfall hazard was introduced from eastern Nebraska to southeast Minnesota for Wednesday, 
April 1 given the sensitivity to any kind of rainfall across this region.

Alaska will continue to remain fairly quiet during the medium range period as surface high pressure 
gets anchored over the mainland. Temperatures across much of the state will be above to much above 
normal, particularly over the North Slope region, but not to the extent that it represents a 
significant hazard. A cyclone may impact parts of the western Aleutians as well during the period, 
but does not look strong enough to pose a threat for any kind of hazards.

Santorelli