Short Range Forecast Discussion
NWS Weather Prediction Center College Park MD
404 PM EDT Sun Oct 10 2021

Valid 00Z Mon Oct 11 2021 - 00Z Wed Oct 13 2021

...Severe weather outbreak and Excessive Rainfall in the Southern Plains
this evening, severe weather in the Great Lakes and Mississippi Valley on
Tuesday...

...Amplifying upper trough to inject some of the coldest air of the season
into the West with heavy mountain snow and much below normal temperatures;
High Winds and freezes in parts of the West...

...Another severe weather outbreak anticipated in the Great Plains on
Tuesday; seasonally warm in the East...

A trio of storm systems are set to unleash a myriad of weather hazards
across the western two-thirds of the Lower 48 the first half of the week.
The first is unfolding in the the northern Great Lakes and northern
Minnesota as an occluded storm system is set to generate strong-to-severe
storms this afternoon and evening. A second storm system is unfolding in
the Southern Plains where a potent cold front and late season dryline are
set to ignite severe storms later today. A Moderate Risk for severe
weather has been issued by the Storm Prediction Center for central and
eastern Oklahoma while the severe threat extends from southwest Missouri
on south into central Texas. There is also a Slight Risk for Excessive
Rainfall in northeast Oklahoma this evening, meaning there is also a
threat for flash flooding. All modes of severe weather; tornadoes,
damaging wind gusts, and large hail are possible within severe storms. By
Monday, the upper trough responsible for the severe weather in the
Southern Plains takes aim at the Midwest causing severe storms to develop
from the mid-Mississippi River Valley to the Great Lakes with localized
flash flooding also possible. The storm system weakens as it tracks into
the northern Great Lakes on Tuesday.

Meanwhile, an impressive upper trough diving south into the Pacific
Northwest is forecast to produce the first significant winter storm of the
season for the northern and central Rockies. The storm's associated cold
front is set to usher in the coldest air of the season to date in the
western third of the country by Monday and persisting into Tuesday. In
wake for the cold frontal passage, high winds will ensue from the Great
Valley of California to the Desert Southwest. High Wind Warnings and Wind
Advisories have been issued in advance for a heightened risk for hazardous
wind gusts. Freeze Watches and Warnings have also been posted for the
western Nevada Basin, and portions of Colorado and New Mexico. As the
front crosses the northern Rockies, plummeting snow levels give way to
periods of snow breaking out Monday morning. As the trough continues to
strengthen, so will the evolving frontal system in the West, causing heavy
snow to envelope many mountain ranges in the Intermountain West. A
developing area of low pressure in the central High Plains keeps heavy
snow and gusty winds in the forecast across the northern and central
Rockies. Latest snowfall forecast indicate anywhere from 12 to 24 inches
(locally higher amounts possible) in the northern Rockies, including
ranges such as the Wasatch, Uinta, Absaroka, Teton, Wind River, and Big
Horns.

This upper trough becomes a vigorous upper low over the Four Corners
region Tuesday morning, setting the stage for yet another severe weather
outbreak in the southern and central Great Plains. The Storm Prediction
Center has an Enhanced Risk for severe weather from southern Nebraska and
central Kansas to parts of the Oklahoma and Texas Panhandle. Excessive
Rainfall is also possible in parts of the Great Plains on Tuesday. While
severe weather erupts in the Plains and cold/snowy conditions take hold of
the West, the East remains under the influence of large scale upper level
ridging, forcing seasonally warm temperatures to stick around from the
Plains to the East Coast.

Mullinax


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