As cool dry subsiding air swept across northern Arizona from the NW today, dew points dropped to as low as -14 F at Winslow AZ this evening.  With a temperature of 56 F, this resulted in a dew point depression of 70 degrees F at 7 pm.  The high temperature today of 61 F at Winslow was some 20 degrees cooler than the first 2 days of April when high temperatures reached 83 and 80 F, respectively.