Get output from robocopy before logfile is written

I have a PowerShell script that executes robocopy like this:

robocopy "D:\source_folder" "\\adrive\destination_folder"  /S /r:2 /w:4 /LOG:$Logfile

It works when the network is up, but when the network is down the log file says:

2016/04/11 14:52:27 ERROR 53 (0x00000035) Accessing Destination Directory \\adrive\destination_folder

The network path was not found.

Waiting 4 seconds... Retrying...

What I want is to get access to the output from robocopy before it writes to a file and test for ERROR 53 and then send myself an email right away, not when the script fails. The way the script works now, it checks the value of $LASTEXITCODE. However, that is unnecessary if robocopy can't find the directory. As well, I'm concerned that by setting the wait time to 4 seconds, it might time out before it finds the network anyway.

Is it possible to get the output of robocopy before writing to the log file?

Thanks