Tropical Cyclone Report - National Hurricane Center - NOAA

Table 5a. NHC official (OFCL) and climatology-persistence skill baseline (OCD5) intensity
forecast errors (kt) for Hurricane Isaac, 21 August – 1 September 2012. Mean
errors for the five-year period 2007-11 are shown for comparison. Official errors
that are smaller than the five-year means are shown in boldface type.
Forecast Period (h)
12 24 36 48 72 96 120
OFCL 3.1 5.3 8.8 11.2 10.2 10.0 11.8
OCD5 5.7 7.3 7.3 8.1 10.7 11.4 9.5
Forecasts 39 39 39 37 33 29 25
OFCL (2007-11) 7.1 10.8 13.0 15.0 16.9 17.1 18.1
OCD5 (2007-11) 8.4 12.4 15.4 17.7 20.5 21.5 21.2
Table 5b. Homogeneous comparison of selected intensity forecast guidance models (in kt)
for Hurricane Isaac, 21 August – 1 September 2012. Errors smaller than the NHC
official forecast are shown in boldface type. The number of official forecasts
shown here will generally be smaller than that shown in Table 5a due to the
homogeneity requirement.
Model ID
Forecast Period (h)
12 24 36 48 72 96 120
OFCL 3.3 5.6 9.6 11.9 10.8 10.2 14.7
OCD5 5.9 7.5 7.3 8.2 11.0 12.1 9.9
HWFI 6.6 9.5 11.9 14.4 12.5 11.2 18.2
GHMI 5.7 7.0 8.3 8.0 9.9 9.2 20.1
DSHP 4.9 9.0 12.9 15.5 13.9 13.6 18.8
LGEM 5.1 7.9 9.9 13.5 16.1 11.6 13.9
FSSE 5.1 8.7 9.7 11.0 8.8 12.1 18.7
ICON 4.6 6.2 6.1 8.7 8.7 8.4 13.4
IVCN 4.6 6.2 6.1 8.7 8.7 8.4 13.4
Forecasts 35 35 35 35 31 25 18
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