Short Range Forecast Discussion
NWS Weather Prediction Center College Park MD
511 AM EDT Wed Sep 28 2022

Valid 12Z Wed Sep 28 2022 - 12Z Fri Sep 30 2022

...The core of Major Hurricane Ian is forecast to make landfall on the
west coast of Florida late today/tonight; Ian's interaction with a front
will likely prolong impacts from high winds, heavy rain, and flooding even
for areas further inland...

...Cool and rainy weather over the Great Lakes today; cool and dry weather
for the rest of the eastern half of the country but heavy rain and strong
winds from Ian is forecast to edge toward the Southeast U.S. on Friday...

...Well above average temperatures persist across much of the West, with
excessive heat continuing over parts of southern California, followed by
arrival of rain and cooler temperatures over the Pacific Northwest later
today and into the northern Rockies on Thursday...

After emerging from Cuba, Ian continues to maintain major hurricane
intensity and most recently has strengthened into an extremely dangerous
Category-4 as it tracks steadily north-northeast toward the west coast of
Florida this Wednesday morning.  Rainbands associated with Ian have
already produced tropical storm force winds and hurricane force wind gusts
over the Florida Keys.  The core of the hurricane is forecast to make
landfall later today/tonight on the west coast of Florida where the
combination of hurricane force winds, storm surge and torrential rain will
likely result in severe to devastating impacts to coastal communities. 
Meanwhile, Ian is forecast to slow down its forward motion as it interacts
with a stationary front settling across northern Florida.  This
interaction will likely prolong the threat of heavy rain and high winds
near and to the northeast of where Ian makes landfall.  How fast/slow Ian
moves will partly depend on how fast/slow an amplified upper trough
retreats into eastern Canada as well as how fast/slow Ian interacts with
the front.  Latest model runs depict a somewhat faster motion across the
central portion of the Florida Peninsula on Thursday.  Up to two feet of
torrential rain is possible near and just north of the track of Ian.  A
High Risk of excessive rainfall is in place from central to northern
portion of the Florida Peninsula through Thursday.

Ian is forecast to cross the Florida Peninsula and emerge into the
Atlantic by later on Thursday.  Interaction with land will likely weaken
Ian to a tropical storm.  On the other hand, Ian's interaction with the
aforementioned front will help produce an axis of heavy rain just off the
coast of the southeastern U.S. by Thursday night.  The heavy rain is
forecast to push toward the southeastern U.S. on Friday as Ian is poised
to make a second landfall near the Georgia/South Carolina coast.

Elsewhere, fall-like cool temperatures will continue across the Midwest
and Northeast through Thursday as a deep, upper-level trough moves
eastward.  Most of the northern tier states into the interior Northeast
will see highs in the upper-50s and low-60s through Thursday, while Freeze
Warnings and Frost Advisories are in effect this morning over the Upper
Midwest and Great Lakes.  A cold rain will remain today near and downwind
from the Great Lakes but as a large high pressure system builds in from
Canada, dry and cool conditions will expand across much of the eastern
half of the country outside of Ian Thursday and into Friday.

Across the western U.S., above-average temperatures will remain over the
region as a strong upper-level ridge moves eastward. Temperatures are
forecast to soar into the 100s and 90s for the desert southwest and
interior southern California, with Excessive Heat Warnings and Heat
Advisories remain in effect for the Los Angeles and San Diego metro areas
through this evening.  Later today, moisture ahead of a Pacific cyclone is
forecast to reach the Pacific Northwest, bringing a period of unsettled
weather inland as well as a general cool down to the region.  Rain
associated with the system is expected to reach the northern Rockies
tonight and into Thursday morning.  Another impulse of energy will keep
the rain over the northern Rockies later on Thursday with high-elevation
wet snow possible over northwestern Wyoming by Friday morning.  Meanwhile,
some monsoonal moisture is forecast to return near/west of the Four
Corners region.

Kong


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