Short Range Forecast Discussion
NWS Weather Prediction Center College Park MD
400 AM EDT Mon Sep 26 2022

Valid 12Z Mon Sep 26 2022 - 12Z Wed Sep 28 2022

...Threat of a major hurricane increasing along the west coast of Florida
by Wednesday...

...Cool and unsettled weather expected to persist across the Northeast and
Great Lakes over the couple of days...

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

An amplifying upper-level trough is forecast to continue bringing cool and
unsettled weather from the Great Lakes to the Northeast for at least a
couple more days as Ian, currently over the Caribbean Sea, is forecast to
move into the eastern Gulf of Mexico and intensify rapidly into a major
hurricane.  The strength of the upper trough will be maintained by
reinforcing surges of cooler air diving across central Canada.  This
pattern will favor damp, dreary and raw weather to persist over the Great
Lakes and parts of the Northeast into Wednesday.  The combination of cold
air aloft flowing across the warm waters of the Great Lakes will
destabilize the atmosphere and could lead to heavy lake-effect rain
through Tuesday and into early Wednesday.  These showers could lead to
isolated flash flooding downwind of Lake Erie and Lake Ontario. Outside of
the Great Lakes and the Northeast, partly cloudy skies with below average
temperatures are expected to extend southward throughout much of the
Midwest, Ohio Valley, and into the interior Southeast. 

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.

All eyes will then turn toward the eastern Gulf of Mexico as Ian is
forecast to rapidly intensify into a major hurricane and move generally
northward during the next couple of days.  Areas of heavy rain across the
Keys to southern Florida is forecast to become heavier and more frequent
as the outer rainbands associated with Ian approach.  Heavy squally
weather could impact the west coast of Florida by Wednesday.

Kong

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