library(HURDAT)
library(knitr)
library(purrr)
library(rrricanes)
## rrricanes is not intended for use in emergency situations.
library(rrricanesdata)
library(stringr)
gis <- flatten(gis_latest(verbose = FALSE))
# Keys of existing storms
keys <- str_extract(names(gis), "(^[[:alpha:]]{2}[[:digit:]]{6})") %>% 
  toupper() %>% 
  unique() %>% 
  .[complete.cases(.)]

Atlantic Basin

keys_al <- keys[str_which(keys, "^AL.")]
if (is_empty(keys_al)) {
  src <- "There are no storms in the Atlantic basin."
} else {
  src <- walk(keys_al, function(x) {
    knit_expand(file = "child_storm.Rmd", 
                arguments = list(key = x))
  })
}

AL112017

East Pacific Basin

(keys_ep <- keys[str_which(keys, "^EP.")])
## [1] "EP142017"