El Nino 2023-24 continues to develop and oceanic El Nino is now classified as moderate-to-strong in intensity. The Climate Impact Company constructed analog forecast projects additional strengthening with peak intensity in December followed by weakening early in 2024. El Nino 2023-24 ends by next May and is followed by the return of a weak La Nina later next year.

In today's U.S. Holiday Report, significantly cooler adjustments are made for next week's forecast. However, of concern is an emerging tropical disturbance in the east-central North Atlantic tropics given a 90% chance to become a tropical cyclone by NOAA and projected to reach major hurricane intensity in 4-5 days by tropical cyclone models. Operational models suggest an East Coast threat in 10 days.

ECM (and GFS) project a Mid-Atlantic heatwave for next week. The hot weather begins on Sunday and strengthens rapidly on Labor Day. The following work week brings persistent heat beneath sunny skies each day particularly in the Mid-Atlantic region. High temperatures are consistently in the mid-to-upper 90’s in the Washington, DC area with a string of 97’s as far west as Cincinnati.

Idalia has realized the potential energy produced by 87F/31C ocean water temperatures and intensified rapidly to a 940 MB category-4 major hurricane this morning. Additional intensification is likely before landfall along coastal Taylor County around 8AM this morning. NOAA/NHC has increased their storm surge forecast to 12-16 feet near and east of the landfall location.