Looking at the radar wind profiler south of Deming we see a change in transport direction right about time, moving from a southeasterly direction to a southwesterly wind.
It's possible that smoke smoke from a fire in Mexico was transported north and visible as the afternoon peak in PM. The NOAA HMS smoke fire location map is shown below. The analyst noted the smoke plume being transported toward the northwest but winds could have shifted but it's hard to say for sure.
Looking at the forecasts it is supposed to warm up to 69F on Friday and 68F on Saturday. A shortwave trough and backdoor cold front is forecasted to drop in for a visit on Saturday night bringing in some wind and cooler temperatures for Sunday and early in the week. As of 11 pm most of the study area is under a moderate air quality (AQI) rating.