Short Range Forecast Discussion
NWS Weather Prediction Center College Park MD
326 PM EDT Fri Oct 27 2023

Valid 00Z Sat Oct 28 2023 - 00Z Mon Oct 30 2023

...Heavy rain and scattered areas of flash flooding will be possible from
the Southern Plains through the Lower Ohio Valley...

...Moderate to locally heavy snow forecast across the Central Rockies and
Front Range this weekend...

...Bitter early season cold snap expected across much of the Great Plains
and Rockies, while record-breaking warmth is found across the East and
Gulf Coast...

...Very dry and windy conditions developing across California by Sunday
will increase the threat for wildfire activity.

The main weather feature impacting the Nation through this weekend will be
a strong autumn frontal boundary responsible for separating
record-breaking warmth in the Deep South and East from early season Arctic
air dropping south across portions of the north-central United States.
This front will be settling south and east with time and will drive an
elongated axis of heavy showers and thunderstorms tonight into Saturday
from the Southern Plains through the Lower Mississippi Valley. Gradually
these heavy rains will advance northeast into the Ohio Valley Saturday
night and Sunday as multiple waves of low pressure advance northeastward
along the front. Locally a few inches of rain can be expected in vicinity
of the front, and given the multiple rounds of heavy rain, scattered areas
of flash flooding will be possible through the weekend. A Slight Risk
(level 2/4) of Excessive Rainfall has been issued for each day through
Sunday.

As the front banks up against the Rockies and the Front Range, an upper
trough will be digging across the Intermountain West on Saturday, and then
ejecting east out into the High Plains on Sunday. Heavy snowfall will
impact the Central Rockies with somewhat lighter amounts spreading across
the Front Range and the adjacent High Plains. Winter Storm Warnings have
been issued for the mountainous terrain of western Colorado, where as much
as 1 to 2 feet of snow is expected this weekend. Lesser amounts to as much
as 4 to 6 inches can be expected from the Front Range through northeast
Colorado and into the Nebraska Sandhills. This will include the Denver
metropolitan area. A strong area of high pressure system nosing southward
into the northern/central High Plains will produce plenty of cold air for
the aforementioned snowfall, while also leading to single digit low
temperatures across parts of Montana, Wyoming, and North Dakota. A few
daily low temperature records are not out of the question Saturday morning
and this will give the northern High Plains an early dose of mid-winter
weather.

This same area of strong high pressure will force a cold front passage all
the way through the entire Great Basin and the Desert Southwest by the end
of the weekend. Cooler temperatures will arrive as a result, but as high
pressure builds southward, much drier air along with strong, gusty winds
will begin to impact California. This will set up a Santa Ana wind event
for southern California by Sunday, and will result in a developing
critical threat of wildfire activity for the Transverse Ranges and the Los
Angeles Basin.

Elsewhere, and opposite of the bitter cold in the north-central U.S.,
summer-like temperatures are in the forecast from the Tennessee Valley and
Gulf Coast states to the Northeast through at least early this weekend.
Strong southerly flow ahead of the approaching cold front will create dry
conditions and temperatures 10 to 30 degrees above late-October averages.
Afternoon highs are forecast to reach into the low-to-mid 80s for most
locations and could break numerous daily high temperature records. A quick
reprieve back to colder weather though is expected across the Northeast
and northern Mid-Atlantic on Sunday along with a likelihood for scattered
areas of showers as the cold front crosses this region. Meanwhile,
temperatures across the Tennessee Valley and Southeast should remain very
warm through Sunday with highs here staying in the 80s ahead of the front.

Snell/Orrison

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