“Reports that say that something hasn’t happened are always interesting to me, because as we know, there are known knowns; there are things we know we know. We also know there are known unknowns; that is to say we know there are some things we do not know. But there are also unknown unknowns – the ones we don’t know we don’t know. And if one looks throughout the history of our country and other free countries, it is the latter category that tend to be the difficult ones.” – Donald Rumsfeld
The quote above is often ridiculed, but it’s actually a brilliant description of Joaquin. In fact. the insurance and reinsurance industry are all too familiar with knowns and unknowns. Model uncertainty is part of doing business, and it is common knowledge that all catastrophe models have some degree of unknown error. There has been a push by insurance companies to funnel better location-level data into the catastrophe models in an effort to limit the overall model uncertainty in modeling risk at a location level.
Weather models are similar to catastrophe models in terms of uncertainty: uncertainties exist in every model run; but generally, the more detailed the input, the greater the accuracy of the output. Better input helps limit uncertainties. Already this year we anxiously awaited the arrival of a Tropical Storm Erika as a catastrophic hurricane to impact Florida hurricane, only to watch Erika fizzle a couple hundred miles south of Cuba.
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Meteorologist view after every new forecast model run for Hurricane Joaquin
I have highlighted the overall uncertainty in Joaquin’s forecast track all week. As anticipated, we have already seen the model and official forecast for Joaquin change drastically from east to west to back east. Most arm chair meteorologist are unaware that behind the scenes increasing amounts of data detail are feeding the weather models to try to get a better picture of the overall atmosphere. Extra weather balloons are being launched at sites all over the Eastern U.S and Caribbean. NOAA and the U.S. Air Force have multiple aircraft sampling the environment in and around Joaquin. All this data is being fed into the weather model to hopefully limit overall uncertainty: just like in a catastrophe model.
Ironically, with more detailed input, the overall forecast for Joaquin has become more certain, but yet the overall track options for Joaquin extend past the National Hurricane Center’s (NHC) cone of uncertainty in this case. In my opinion, Bermuda, which is not even in the cone of uncertainty, is just as likely as Boston to feel Joaquin’s impact.
In the short term, Joaquin will significantly impact the islands of the Bahamas as Joaquin will fluctuate in intensity as a major hurricane for the next 24 – 36 hours. As mentioned yesterday, after 36 hours the door is wide open for several different track paths. A U.S. landfall is still possible, but the new forecast models (that are being fed all this higher resolution data) suggest a more eastward shift in track away from a U.S. landfall.
I consider the ECMWF model (image below -Right) to be very good and reliable, and it illustrates Joaquin moving out to sea and closer to Bermuda. I expect by Friday we will have a much clearer picture of where Joaquin will track this weekend, and with that, insured impacts can start to be calculated.
American (GFS Model) left and the European (ECMWF Model) right ensemble runs which in total is over 75 separate model runs of possible tracks for hurricane Joaquin.
So until the track is known it’s best to focus on what is known:
- As Joaquin funnels tropical moisture northward, rainfall totals will continue to increase across much of the East Coast regardless of whether the hurricane hits land. Over a foot of rain could occur in some area which will produce flash flooding.
- Minor coastal flooding is already occurring along the East Coast from strong onshore winds being funneled between Joaquin to the south and strong Canadian high pressure to the north. That flooding will likely worsen over the next few days, regardless of the track of Joaquin