The latest seasonal totals so far assembled by Colorado State University (CSU) indicates 11 tropical storms have formed with 3 reaching hurricane strength including 2 major hurricanes. The accumulated cyclone energy (ACE) index is 48.6 compared to the normal value for this date of 36.3. Using the ACE index, the 2023 season so far is judged about 33% more intense than normal.

Let’s take a quick look at verification of Climate Impact Company constructed analog forecasts, made in late April, for June and July 2023. A constructed analog forecast is based on regional SSTA patterns and their historical relationship to upper air patterns that drive our sensible weather.

In the North Pacific, an immense MHW has strengthened across the northwest basin. Similarly, MHW NEP23A in the northeast Pacific has strengthened and shifted to the northwest coast of North America. In the North Atlantic basin, the North Atlantic warm hole (NAWH) recently shifted to coastal West Europe. However, the rapid development of a MHW off Newfoundland during late spring is now weakening quickly. The MHW off northwest Africa extending to the western Mediterranean Sea has weakened slightly.

We’ve entered the most active part of the North Atlantic basin tropical cyclone season (after Aug. 1st). For now, the basin is all clear. However, normal to above normal hurricanes/major hurricanes remain in the forecast primarily due to the record warm surface of the North Atlantic tropics/subtropics. The forecast is unique, a potential big year for hurricanes in the face of a developing El Nino climate. Provided are the latest daily SSTA analysis for the Gulf of Mexico, western North Atlantic, and main development region (MDR) in the outer tropics. The Gulf and MDR are record warm. Given the super warm SST, if the proper environment evolves, the potential for unusually strong hurricanes is high!