A large increase in MHW’s during the past decade appears to be a leading contributor to global ocean temperature rise and Australia is a location directly affected by the attendant climate produced by MHW’s.

As a review, an exceptionally intense severe weather episode was observed late last week across the Upper Midwest, Midwest, and Mid-Atlantic States. On May 15 (Thursday), NOAA/SPC’s final count of severe weather reports is 657 including an unusually high amount of hail (274) plus 32 tornado reports. On May 16 (Friday), NOAA/SPC counted 1, 216 damage reports including a whopping 371 hail damage events and 815 wind damage reports.

The official start of the North Atlantic basin tropical cyclone season is June 1st. During the active tropical cyclone season period of 2016-2024 when an average of 18-19 named storms have generated each year, the North Atlantic has averaged much warmer than normal and a likely catalyst to the active period. As mid-May approaches, the North Atlantic basin is marginally warm (+0.37C) and 0.23C cooler than 1 year ago.

The primary culprit to the extreme heat observed across much of Australia during the past 3 months is the enhancing influence on subtropical upper-level high-pressure ridging stretching from southeast of New Zealand to Southern Australia by the presence of MHW’s.