First cool-weather outdoor brewing questions....

I just started brewing outdoors earlier this summer, so today is my coldest outdoor brewday so far. It's also the first problematic brewday -- I've been pumping heat into 12 gallons of wort (in a converted sankey) for over two hours, and it's barely at 190 up from 150 at the end of the sparge. Is this out of line for a windy 40-ish day, or am I doing something grossly wrong? I'd hate to have to move back into the warm indoors, and be stuck with 5 gallon batches this winter :-( I'll need to work on some windscreening, for sure -- the lawn chairs and buckets I'm using now don't cut it. Will I need to look into insulating the Sankey? -- Chris Mikkelson | That is a form of errant pedantry up with which chris(a)mikk.net | I will not put. | -- Winston Churchill