65th IHC Booklet/Program (pdf - 4.9MB) - Office of the Federal ...

Enhancements to the SHIPS Rapid Intensification Index
John Kaplan 1 , Joe Cione 1 , Mark DeMaria 2 , John Knaff 2 , Jason Dunion 3 , Jeremy Solbrig 4 , Jeffrey
Hawkins 4 , Thomas Lee 4 , Evan Kalina 5 , Jun Zhang 3 , Jack Dostalek 6 , Paul Leighton 1
(John.Kaplan@noaa.gov)
1 NOAA/HRD; 2 NOAA/NESDIS; 3 CIMAS/HRD; 4 NRL; 5 CU; 6 CIRA
Predicting the timing, magnitude, and duration of episodes of tropical cyclone rapid
intensification (RI) remains one of the most challenging problems in tropical cyclone forecasting.
In recent years, a statistically based rapid intensification index (RII) that uses predictors from the
SHIPS model to estimate the probability of RI has been developed for operational use by
forecasters at the National Hurricane Center (NHC) for systems in the Atlantic and eastern North
Pacific basins. Although the operational RII forecasts exhibited some skill in each of the
aforementioned basins when validated for the recent 2008 and 2009 Hurricane seasons, the skill
of the RII was relatively low in the Atlantic basin and only in the low to moderate range in the
eastern North Pacific basin. Thus with support from the NOAA Joint Hurricane Testbed (JHT),
research is currently being conducted to improve the operational RII by including predictors
derived from three new sources of inner-core information. The first of these three new sources is
the time evolution of the structure of the inner-core as deduced using standard principlecomponent
analysis of GOES infra-red (IR) imagery while the second is microwave-derived total
precipitable water. The final source is lower tropospheric GFS model temperature and moisture
data and sea-surface temperature estimates derived from an inner-core sea-surface temperaturecooling
algorithm.
In year 1 of this JHT proposal, an experimental version of the SHIPS rapid intensification
index (RII) was developed for the Atlantic basin utilizing predictors from these three new
information sources. This new experimental version of the Atlantic RII was tested in real-time
during the latter part of the 2010 Atlantic Hurricane Season for the first time. A verification of
these real-time forecasts as well as those that were obtained by re-running cases that occurred
prior to the commencement of these tests using real-time GFS data and operational NHC track
forecasts will be shown. More recently, an experimental version of the RII was also developed
for the eastern North Pacific basin using predictors that were quite similar to those that were used
to derive the experimental Atlantic version. The results of these efforts will also be presented at
the conference.
Session 12 – Page 2