Short Range Forecast Discussion
NWS Weather Prediction Center College Park MD
400 AM EDT Wed Aug 30 2023

Valid 12Z Wed Aug 30 2023 - 12Z Fri Sep 01 2023

...Hurricane Idalia will bring catastrophic and life-threatening winds and
storm surge to portions of Florida's northern Gulf Coast today...

...Areas of Flash, urban and moderate river flooding, with considerable
impacts, are expected from the Florida Big Bend through eastern North
Carolina into Thursday...

...Flash Flooding possible over parts of the Northern Rockies today...


Hurricane Idalia is expected to make landfall this morning as a major
hurricane. Catastrophic impacts from storm surge inundation of 12 to 16
feet above ground level and destructive waves are expected between the
Wakulla/Jefferson County line and Yankeetown, Florida. Life threatening
storm surge inundation is likely elsewhere along portions of the Florida
Gulf Coast, where a Storm Surge Warning is in effect. Residents in these
areas should follow advice given by local officials. There is also
potential for destructive life-threatening winds where the core of Idalia
moves onshore in the Big Bend region of Florida, with hurricane conditions
expected elsewhere in portions of the Hurricane Warning area along the
Florida Gulf Coast. Strong winds will also spread inland across portions
of northern Florida and southern Georgia near the track of the center of
Idalia where Hurricane Warnings are in effect. Residents in these areas
should be prepared for long-duration power outages. Damaging
hurricane-force winds are possible in portions of eastern Georgia and
southeastern South Carolina where Hurricane Watches are in effect.

Additionally, Idalia is expected to produce a swath of 4 to 8 inches of
rainfall with isolated maxima up to 12 inches from the Florida Big Bend
through central Georgia and South Carolina, and through eastern North
Carolina into Thursday. As a result, a high end Moderate Risk of Excessive
Rainfall leading to Flash Flooding is in effect for a swath extending from
Florida's Big Bend region to southeastern North Carolina today. A Slight
Risk is in effect for eastern North Carolina into southeastern Virginia on
Thursday as Idalia pushes out into the Atlantic.

Meanwhile, a potent shortwave trough will interact with anomalous moisture
over the Northern Rockies today. This will lead to scattered showers and
thunderstorms for the region. Rainfall will be enhanced by terrain over
parts of northern Washington/Idaho and western Montana where a Slight Risk
of Excessive Rainfall is in effect. Rainfall totals of 1-2" are possible
over this area by Thursday morning. High temperatures in the 60s and 70s
over parts of the Northwest today and tomorrow will be 15-25 degrees below
average. The Southwestern ridge begins to retreat back east into the
Central U.S. today. This will result in diminishing excessive heat threats
over the Southwest. An amplifying upper pattern over the West will support
enhanced southerly flow into the Four Corners region which will in-turn
lead to increased excessive rainfall concerns over the area heading into
this weekend.


Kebede


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