Very Mild Morning - At Least For Most Of Metro Tucson

This morning illustrates nicely what a tremendous challenge it is to forecast minimum temperatures across the Tucson metropolitan area, under certain synoptic settings. The current, pronounced easterly pressure gradient (4 to 5 mb from Tucson to Deming NM) led to winds occurring much of the night across most of the city. However, some places experienced at least a brief period of nearly calm winds, and these areas recorded much lower minimum temperatures. So, we find that low temperatures only fell to 64F at the airport, DM AFB and the Atmo weather station; however, here at the house the low was 48F and the low at the Empire RAWS station (4650 ft MSL) was 45F. The Empire site apparently had nearly calm winds during only 1 hour - as per, 6 am 55F; 7 am 45F; and 8 am 63F. I don't have wind data here at house, so I don't know how long the winds dropped off. The other nearby, high elevation, RAWS sites were just as variable - Rincon at 8209 ft MSL had a low of 47F, while Mt. Hopkins at 7120 ft MSL came in with 56F. The NWS forecast lows for tomorrow morning from Green Valley north across the metro area are in the low to middle 50s - which seems like a middle-of-the-road approach, splitting the difference between what the temps might be in calm vs. windy conditions.
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Out of curiosity, I took a quick look at the Univ. of Arizona Atmo run of the WRF-GFS model initialized at 11 pm last night. The WRF forecast of 10m winds, valid at 6 am, is shown in the top graphic. The model forecasted higher winds at higher elevations, and, significantly for temperatures, a band of stronger winds extending from east of Tucson westward across most of the metro area. The model also forecasts very light winds along the Rillito Wash along the north side of the city (the region where the house is and where temperatures are often much colder than the "official" lows). The WRF forecast of 6 am temperatures at 2 m is shown in the bottom graphic. The model accurately forecast the warm temperatures across most of the metro area, but was too warm in the calm area along the Rillito, and also appears too cold at the higher elevations. Again illustrating, what a problem temperature forecasting can be in an orographically complex area such as we live in!