Rodeo :: 98 - Temp Gauge Creeping Up To Hot When Stopped / Coolant Leak?

Got a '98 rodeo 3.2 with 160k. A couple weeks ago when stopping at red lights I noticed the temp gauge creeping up to the hot when stopped. This happened about 4 years ago and I was just low on coolant. I kind of figured that was the problem this time and added coolant. Then I started noticing coolant on the ground dripping from the skid plate a little toward the passenger side. The vehicle is parked on the street in front of my house so the vehicle may lean slightly to the passenger side. This rodeo is only driven during the week and then sits for 2-3 days on the weekend.

Over the last couple weeks I have noticed that it doesn't really leak during the week when it's being driven daily and if it does, it's just a drop or two. Now when it sits for 2-3 days there is a pizza sized leak under the vehicle probably about 18 inches wide. Since the overflow wouldn't hold coolant, I figured that it was cracked or had a leak. I removed the reservoir and didn't find a leak. I seen no evidence of a leak anywhere else, however since it's dripping from the skid plate, I assume that it's leaking on the front side of the engine. What to check. Seems strange that it doesn't really leak when running or hot, only when sitting for a few day.