Short Range Forecast Discussion
NWS Weather Prediction Center College Park MD
334 PM EDT Sun Sep 25 2022

Valid 00Z Mon Sep 26 2022 - 00Z Wed Sep 28 2022

...Cool and unsettled weather expected across the Northeast and Great
Lakes over the next few days...

...Well above average temperatures forecast throughout the West, with
excessive heat impacting parts of southern California...

...Isolated flash flood concerns for portions of central and southern
Florida through Monday before hazardous conditions associated with
Tropical Storm Ian approach southern Florida on Tuesday...

A potent upper-level low churning over the Upper Great Lakes and southern
Ontario, Canada will be slow to exit the region and continue to aid in
producing damp and dreary weather over the Great Lakes and parts of the
Northeast through early this week. Meanwhile, an advancing cold front
swinging across the Mid-Atlantic could lead to isolated severe
thunderstorms this evening, particularly from southern Connecticut to the
northern Delmarva Peninsula. A few storms could contain damaging wind
gusts, large hail, and isolated tornadoes. This has prompted the Storm
Prediction Center to issue a Slight Risk (level 2/5) of severe
thunderstorms for the region. For the Great Lakes, the combination of
strong westerly winds, cold air aloft, and warm lake temperatures could
lead to locally heavy lake-effect rain through Tuesday. These showers
could lead to isolated flash flooding downwind of Lake Erie and Lake
Ontario. Lastly, below average temperatures are likely underneath the
upper-level trough and overcast skies. Highs into the 60s and 50s are
forecast throughout much of the Midwest, Ohio Valley, and Northeast.

Summer-like and excessive heat are forecast to remain over much of the
West as a strong upper-level ridge passes over the western half of the
Nation. The hottest weather is expected over the Southwest and southern
California. Highs early this week are expected to top 100 degrees for the
interior deserts and typically hot valley locations. Excessive Heat
Warnings and Heat Advisories are in effect for parts of southern
California. Elsewhere, well above temperatures stretch from the
Intermountain West to the northern Rockies and northern High Plains. Highs
on Monday and Tuesday are forecast to soar into the upper 80s and low 90s.

The other area of potentially impactful weather through the first few days
of the new workweek will be located across Florida. Through Monday night,
a lingering frontal boundary may provide focus for developing
thunderstorms across the southern half of the Peninsula. These storms may
be slow-moving and contain intense rainfall rates. By Tuesday morning,
outer rainbands associated with Tropical Storm Ian may begin to approach
southern Florida and the Florida Keys. The greatest potential for
tropical-storm force wind gusts through Tuesday are expected to be across
the western Florida Keys and southwestern parts of the state. Heavy rain
and gusty winds are also forecast to slowly spread northward into central
Florida through early Wednesday as Ian pushes into the eastern Gulf of
Mexico. Flash and urban flooding is possible across the Florida Keys and
Florida Peninsula throughout midweek. In order to further highlight the
concern, a Slight Risk (level 2/4) of Excessive Rainfall has been issued
for the southern half of the Sunshine State on Tuesday.

Snell

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