Sudden cold front temperature change

A fantastic wind shift and cold front passage last night dropped temperatures by twenty degrees Fahrenheit in the course of a few minutes. As is common here, the cold front used the lake as an expressway south to accelerate and end an otherwise warm and humid Memorial Day. As experienced by me, a quiet warm night suddenly grew loud as the trees shook, then a blast of cold air blew through my open windows in a gust. Another account.

This data is from the Ryerson weather station.
--Timestamp--- Temp Humid Dewpt Wind HiWind WindDir
20080526 19:30 80.6 57 63.9 8 18 247
20080526 20:00 79.8 58 63.7 6 15 247
20080526 20:30 79.0 61 64.4 5 13 270
20080526 21:00 78.2 63 64.6 4 13 247
20080526 21:30 77.6 66 65.3 5 11 247
20080526 22:00 76.8 67 65.0 5 11 247
20080526 22:30 76.1 69 65.2 4 11 270
20080526 23:00 54.3 73 45.8 10 35 270
20080526 23:30 51.9 78 45.3 18 41 0
20080526 24:00 48.8 82 43.6 18 33 0


One of the few storms that popped up on the warm side earlier that evening
Is this cloud from the cold air bumping the warm humid air up and out of the way?