The Pr Philip J. Klotzbach from the University of Colorado Atmospheric Research Department and his team have updated their forecast for the 2020 hurricane season.
| Forecast. April | Forecast. June | Average | 2019 | 2018 | 2017 | |
|---|---|---|---|---|---|---|
| Nb of named storms | 16 | 19 | 12 | 18 | 15 | 17 |
| Of stormy days | 80 | 85 | 59.5 | 68 | 87 | 91 |
| No. of hurricanes | 8 | 9 | 6.5 | 6 | 8 | 10 |
| No. of hurricane days | 35 | 40 | 24 | 23 | 26 | 51 |
| No. of major hurricanes | 4 | 4 | 2.7 | 3 | 2 | 6 |
| No. of major hurricane days | 9 | 9 | 6 | 10 | 5 | 19 |
| Cumulative energy (ACE) | 150 | 160 | 106 | 142 | 129 | 220 |
Summary
The update integrates the 3 early cyclones of the last few days into the total. Additional hurricane risk has been added. Apart from taking into account past or current systems, there is no major change. Nonetheless, with the early systems past or underway, this season will be well above average.
Details of the update of June 4, 2020
The hurricane forecast for a few months is based on 2 major parameters: the situation and the evolution of the oscillation ENSO and the situation and evolution of surface water temperatures in the MDR. These 2 parameters have changed slightly over the last 2 months.
Prediction ENSO for this summer and autumn is a little more marked for a phase transition La Nina low from September until the end of the year. However, given the uncertainty of this type of forecast, which we still have little control over, such a small difference is not necessarily significant. The trend is on the other hand strong for a mild cold episode (cold neutral phase or La Nina low) which largely explains the activity forecast for this season.
The pattern of water temperature anomalies over the North Atlantic is unusual. On the one hand, the very cold temperatures in the north suggest that the North Atlantic Multidecadal Oscillation (AMO) is in a negative phase, but the very high temperature in the western subtropical zone invalidates this analysis.
These medium and large-scale climatic oscillations are still very enigmatic and forecasting and analysis models still often encounter unexpected situations.
The eastern half of the Major Development Zone (MDR) remains with water temperatures close to the average and for the moment this is what interests the West Indies at first. But the very high levels in the Caribbean Sea, the Gulf of Mexico and the subtropical Atlantic mark an already high risk for these areas. And it is also in these areas that the early storms of the 2020 season developed.
Conclusion
The 2020 hurricane forecast update does not fundamentally change what was forecast. It incorporates the early systems of the last few days and does not specifically modify the risk for the season.
Let us not forget, however:
- These forecasts are uncertain like all atmospheric forecasts.
- These forecasts are global, which makes anticipation impossible for a territory.
Consequently, whatever the forecast, we must prepare each season in the same way, as if our territory was going to be impacted. This is the only solution to be as resilient as possible.
Download the full original document in PDF 
The next forecast will be released by the same team on July 7 and will be even more refined.
