A broad upper low positioned over the western US resulted in critical fire weather and winter weather conditions across High Plains on 09 Nov 2022. By the start of the day, an east-west oriented quasi-stationary cold front was draped across northern Colorado. IR satellite imagery captured the exact position of the cold front during the day, filling temporal and spatial gaps between surface obs.

In order to save screen space, and monitor the position of the cold front in addition to clouds and aerosols, one can create a semi-transparent IR overlay on Geocolor imagery. In this case, south of the front, gusty southwesterly winds brought temperatures into the 60s – 70s, critical fire weather conditions, along with blowing dust across southern Colorado. North of the front, temperatures stayed in the 30s-40s during the day, with weaker easterly winds and low stratus well northeast of the boundary.

NWS/BOU leveraged GOES Imagery in a similar manner: “There are a lot of interesting features on satellite today. The low clouds and fog have stuck around in the far northeast corner keeping temperatures near freezing in Sterling and Julesburg. Meanwhile, a sharp boundary has been draped across the east central plains which is obvious on the shortwave IR from the southeast Denver metro to central Washington County. There are critical to extreme fire weather conditions to the south of this boundary with no fire weather concerns to the north of this boundary. Limon is currently 74 degrees with a relative humidity of 5 percent with gusts up to 53 mph. The Red Flag Warning is verifying there and the warning will be kept in its current state until it expires at 7pm. Latest visible satellite data also shows a couple areas of blowing dust mainly in eastern Arapahoe County and nearby areas.”

Focusing further south, we observe considerable blowing dust in GOES-East Geocolor Imagery out of the San Luis Valley. From NWS/PUB: “As the pressure gradient tightens overhead, southerly and southwesterly winds in excess of 50kt have been reported across the forecast area, and a thick area of blowing dust can be seen across the northern San Luis Valley on enhanced satellite imagery. Alamosa is reporting 2 miles visibility in blowing dust.”

Bill Line, NESDIS/STAR