Yes, the weather was brutal that late November Sunday night in 2019. But the three previous games in Foxborough the weather was okay - and the Cowboys still lost.
October 16, 2011: late Sunday afternoon kickoff - temps in mid 60s & windy, no precipitation; DAL 16, NE 20
November 16, 2003: Sunday night kickoff - temps in mid 40s, low winds, no precipitation; DAL 0, NE 12
December 5, 1999: Sunday night kickoff- temps in low 50s, winds 10 mph, no precipitation; DAL 6, NE 13
And let's not leave out the Cowboys' losses at home to the Patriots -
Mid-October 2007 @ Texas Stadium - NE 48, DAL 27
Mid-Ocother 2015 @ AT&T Stadium - NE 30, DAL 6
Cowboys have lost to Patriots the last six straight games....no matter the location, time of year, or the weather.