Creates a county choropleth map customized for displaying hurricane exposure. This function is used as a helper function within other mapping functions in the package.
hurr_choropleth(
  map_data,
  metric = "distance",
  wind_var = "vmax_sust",
  wind_source = "modeled"
)A dataframe with columns with FIPS numbers (in numeric
class) for all counties in the eastern US (region) and the
exposure value (value)
Character string giving the metric to plot. Current options are
"distance", "wind", and "rainfall". These options are used
to customize the color palette and scale of the choropleth map produced
by this function.
A character string giving the wind variable to use. Choices
are "vmax_sust" (maximum sustained winds; default), "vmax_gust"
(maximum gust winds), "sust_dur" (minutes of sustained winds of 20 m / s
or higher) and "gust_dur" (minutes of gust winds of 20 m / s or higher).
If the Extended Best Tracks wind radii are used as the source of wind data,
the "gust_dur" option cannot be selected.
A character string specifying the source to use for the winds. Options
are "modeled", for estimates based on running a wind model from Best
Tracks data inputs, and "ext_tracks", for estimates based on
the wind radii in the Extended Best Tracks data. See the help files for the
datasets storm_winds and ext_tracks_wind in the
hurricaneexposuredata package for more details on each of these sources
for wind estimates. For the gust wind estimates, these are based on applying
a gust factor of 1.49 to the sustained wind estimates in both wind data sources.
A ggplot object with a map of hurricane exposure in eastern
   US counties
The function only maps counties in states likely to be exposed to Atlantic basin tropical storms.