2000 Jeep Grand Cherokee coolant leak need help?

Okay lately when I start mymy truck I been hearing a squeal sound and I thought it was the belt making noise because its cold and wet out. But today was warm almost 60 degrees outside I go start my truck and im hearing a loud squeal with a grind/growling sound and im looking as the car idled 1-2 mins later I see coolant dripping from the front of the car its travelling down and dripping under the crank pulley it drips a drop a second and is pretty steady but I do see my reservoir tank is little low so I drive it get where im going it stops leaking. Start it up hours later when its cold about 35 degrees out and its screaming loud squeal/grinding sound but its not leaking and the sound disappears after 5-10 mins of idle. Does anyone know what it may be? 2000 jeep inline 6 4.0L with 169xxx miles just had new radiator hoses coolant replaced three months ago and was told I should had done water pump but couldn't afford it