Using pure bash :
$ cat file.txt
US/Central - 10:26 PM (CST)
$ while read a b time x; do [[ $b == - ]] && echo $time; done < file.txt
another solution with bash regex :
$ [[ "US/Central - 10:26 PM (CST)" =~ -[[:space:]]*([0-9]{2}:[0-9]{2}) ]] &&
echo ${BASH_REMATCH[1]}
another solution using grep
and look-around advanced regex :
$ echo "US/Central - 10:26 PM (CST)" | grep -oP "\-\s+\K\d{2}:\d{2}"
another solution using sed :
$ echo "US/Central - 10:26 PM (CST)" |
sed 's/.*\- *\([0-9]\{2\}:[0-9]\{2\}\).*/\1/'
another solution using perl :
$ echo "US/Central - 10:26 PM (CST)" |
perl -lne 'print $& if /\-\s+\K\d{2}:\d{2}/'
and last one using awk :
$ echo "US/Central - 10:26 PM (CST)" |
awk '{for (i=0; i<=NF; i++){if ($i == "-"){print $(i+1);exit}}}'