Save a result based on a command's output in a variable while printing the command output

num_errs=`grep ERROR /var/log/syslog | tee >(cat >&2) | wc -l`
Many circumstances call for creating variable of a summary result while still printing the original pipe. Inserting "tee >(cat >&2)" allows the command output to still be printed while permitting the same output to be processed into a variable.
Sample Output
Mar 11 18:02:35 hostname kernel: [    0.896119] [drm:intel_dp_i2c_aux_ch] *ERROR* 
Mar 11 18:02:35 hostname kernel: [    0.898782] [drm:intel_dp_i2c_aux_ch] *ERROR* 
Mar 11 18:02:35 hostname kernel: [    3.123365] [drm:udl_parse_] *ERROR* 

>> echo $num_errs
3

0
2014-03-12 00:04:24

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