Friday, January 06, 2006

Forecast model of U.S. hurricanes 6 months in advance

Hurricanes are a serious social and economic threat to the
United States. Hurricane Katrina is a grim reminder of this fact.
Recent advances allow skillful forecasts of the U.S. hurricane
threat at (or near) the start of the Atlantic hurricane season.
Skillful forecasts of hurricane landfalls at longer lead times
(forecast horizons) for the complete hurricane season would greatly
benefit risk managers and others interested in acting on these
forecasts. Here we show a model that provides a 6-month forecast
horizon for annual hurricane counts along the U.S. coastline during
the June through November hurricane season. Forecast skill exceeds
that of climatology. The long-lead skill is linked to the
persistence of Atlantic sea-surface temperatures and to
teleconnections between North Atlantic sea-level pressures and
precipitation variability over North America and Europe. The model
is developed using Bayesian regression and therefore incorporates
the full set of Atlantic hurricane data extending back to 1851.

[with R.J. Murnane and T.H. Jagger]