How to Add a Layer with Date Parameter to a WebMap

[NeilJohnston1]

Using ArcGIS Online WebMaps is there a way to add a parameter with the value for the current date?
I have a WMS endpoint of: 
http://cwfis.cfs.nrcan.gc.ca/geoserver/public/wms?SERVICE=WMS&VERSION=1.3.0&REQUEST=GetMap&FORMAT=im... 

And as you'll note there is a current date in the URL (in bold).  Is there a way to add the current date in the YYYYMMDD format to the parameter values via WMS OGC options?

Thanks,

Neil

[KellyGerrow]

Try using custom parameters if there is a key pair relationship for this parameter:

Improved OGC Client Capabilities using Custom Parameters (September 2016) 

Add layers—ArcGIS Online Help | ArcGIS 

-Kelly