Short Range Forecast Discussion
NWS Weather Prediction Center College Park MD
335 AM EDT Tue Apr 13 2021

Valid 12Z Tue Apr 13 2021 - 12Z Thu Apr 15 2021

...A slow-moving storm will bring widespread snows to the Great Basin and
central Rockies, with heavy accumulations for the mountains...

...Strong to severe storms, including damaging winds, large-hail and heavy
rain are expected for portions of eastern Texas and Louisiana...

...Critical Fire Weather conditions are expected across portions of the
Southwest...

A slow-moving area of low pressure will continue to produce widespread
precipitation across the northern Great Plains and Upper Midwest,
including some late-season accumulating snows from Montana to the Upper
Great Lakes.  Precipitation is expected to continue through Tuesday before
diminishing from west to east across the Plains as the system moves east
on Wednesday.  As the system moves east, scattered precipitation will
begin to develop across the Mid-Atlantic and Northeast on Wednesday, with
organized heavier precipitation forecast to develop over the northern
Mid-Atlantic and Northeast by Thursday morning.

A slow-moving frontal boundary to the south, interacting with increasing
moisture, is expected to encourage shower and thunderstorm development
across the southern Plains and lower Mississippi valley on Tuesday and
Wednesday.  There is the potential that some of these storms may become
strong to severe, especially across eastern Texas and Louisiana.  In
addition to concerns for large hail and damaging winds, these storms may
also produce heavy rainfall amounts.  Given the high stream flows and
saturated soils due to recent heavy rains across the lower Mississippi
Valley and central Gulf Coast, the threat for additional heavy rains will
also likely lead to increasing flooding concerns across the region on
Tuesday and Wednesday.

As the lead system over the Midwest drifts east, a second slow-moving
system will develop over the Pacific Northwest on Tuesday and sink slowly
southward into the northern Great Basin by Wednesday.  Increasing
precipitation coverage across the Great Basin and Rockies will include
late-season snows the region.  Snow developing on Tuesday and continuing
through Wednesday into Thursday is expected to result in heavy
accumulations for portions of the region, including the central and to
southeastern Wyoming ranges, as well as the central Colorado and northern
Utah ranges.

In contrast to the wet conditions along the central Gulf Coast into the
lower Mississippi Valley, dry conditions, low relative humidities and
gusty winds will support an Elevated to Critical Fire Weather Threat over
the Southwest Tuesday and Wednesday.  Red Flag Warnings will be in effect
on Tuesday for a significant portion of the California deserts, southern
Nevada, northwestern Arizona and southern Utah. 

Pereira

Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php