what are mean outdoor temperatures?

my heat sux, but it really sux when its below zero. I wear pac boots for long drives- real comfortable to drive in.
I also cover 80% of radiator w/ cardboard during cold months.

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1984 123.193 372,xxx miles, room for Seven.

1999 Dodge Durango Cummins 4BTAA 47RE 5k lb 4x4 getting 25+mpgs, room for Seven.