NM Border Air Quality Blog

Feb. 13 - Evening low wind high PM event - Warm today with high of 69F at NMSU and 68F at the Las Cruces Airport. I recorded a 71F east of town. Low of 29F this morning at NMSU and 27F at the Las Cruces Airport. A very dry airmass has arrived with amazingly low dewpoints that reached -20F this afternoon that results in a 2 percent relative humidity. Our upper level high is driving widespread subsidence over the southwest.  This map shows estimated surface dewpoint temperatures at 00 UTC (5 pm) and much of the region shows below zero dewpoints.

 

We expected light southerly winds this afternoon over our region

 

We had an evening low wind high PM event in the Paso del Norte. We'll take a look at the Sunland Park City Yard station first. Here we saw peak hourly PM10 at  222 µg/m3 at 7 pm and peak PM2.5 at 72 µg/m3 at 8 pm.

 

and a similar pattern at the Anthony Elementary station

 

At the Las Cruces Holman Road site we also saw the highest PM10 during the evening hours. Winds were from the southeast during the peak PM10 at 6 pm.

 

Tomorrow's AQI forecast shows moderate air quality over Dona Ana County.