Short Range Forecast Discussion
NWS Weather Prediction Center College Park MD
343 PM EDT Sun Oct 08 2023

Valid 00Z Mon Oct 09 2023 - 00Z Wed Oct 11 2023

...Colder and wetter weather to arrive on the West Coast Monday, but above
average warmth to remain for portions of the Interior West...

...Below average temperatures continue for the Great Lakes and much of the
eastern U.S., with lake-effect showers in the Great Lakes...

...Potential increasing for heavy rain and the risk for flash flooding for
the Texas Gulf Coast Tuesday following surge of tropical moisture...

It has been a very warm, above average, and even hot weekend for some
locations in the West with an upper-level ridge and mostly dry conditions
in place. However, a storm system in the northeast Pacific is forecast to
arrive along the West Coast Monday morning, bringing increasing
precipitation chances to northern California and the Pacific Northwest,
eventually spreading into the northern Great Basin and Northern Rockies by
Tuesday. Some locally heavy rainfall may occur for favorable upslope
locations along the coastal ranges and the Cascades. Cooler temperatures
will also follow, with highs dropping into the upper 50s and 60s. A second
system approaching by later Tuesday is expected to keep rainfall chances
up into mid-week. Highs will remain above average ahead of the system over
much of the Interior West, with 70s and low 80s for the Rockies and Great
Basin and 90s for the southwestern deserts.

Lingering lake-effect showers will continue in favorable downwind
locations of the Great Lakes as a closed upper-low remains anchored above
the region through at least mid-week. High temperatures will remain much
below average as well, with generally cooler Fall temperatures for much of
the eastern U.S. following a frontal passage this weekend. Forecast highs
Monday are in the upper 40s to 50s for the Great Lakes, with 60s from the
Middle Mississippi Valley east through the Ohio Valley into the Northeast,
and 70s for the Tennessee Valley into the Southeast. Conditions will trend
a bit warmer Tuesday, especially for the Southeast as highs rise into the
low 80s for many locations. Precipitation chances are very low outside of
the Great Lakes except for South Florida as showers and thunderstorms
continue along a stalled frontal boundary.

Conditions will also remain dry Monday for the Plains, with temperatures
trending above average for the High Plains and Southern Plains and at or
below average into the Central and Northern Plains. However, by as early
as Monday night, showers and thunderstorms may begin for portions of the
Texas Gulf Coast associated with the remnants of Potential Tropical
Sixteen in the Pacific. A surge of tropical moisture will lead to
increasingly heavier downpours into Tuesday evening, with a Slight Risk of
Excessive Rainfall (level 2/4) in place for the risk of some scattered
instances of flash flooding.

Putnam

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