BTW-Completed a short slick rock mtb trip in Moab a week ago and it has been a damp spring in the central Rockies thus far. The BLM roads are either squishy mud or dried, deep rutted roads as the BLM-County (neither have the proper funding-remember sequestration?) have yet to significantly blade those roads on the east side of 191.
If you are healthy and in decent shape the hike up to Delicate Arch in the morning or later in day is highly worth it (30-60 mins up).