Yup more questions... What kind of cooler are you using? have you filled the lid with foam? Do you wrap the cooler in a blanket? Just to put it into perspective, I have a 5 gal round rubbermaid cooler. I do not use the lid... I have a round of styrafoam about 1 inch thick wrapped in plastic that I use in its place. I have one of those car windshield insulators that I wrap around the cooler... And I still wrap that with a blanket. After preheating the tun, temp is rock solid after I mash in.
Oh yea I forgot to answer your question... It wouldn't hurt to add some boiling water maybe a cup at a time, stir and check temps till you get back to where you want it.
Drinking Oaked Wee heavy, The Kaiser clone, Graff, , Sour Cranberry Ale
Carbing/Aging Westy 12 (2013),
In the bucket Chocolate stout, Westy 12 (new world)
On Deck Pumpkin Ale 2014, FBS clone, Port oaked amber, Old Rasputin Clone, 15% RIS