Heavy, middle-level cloud cover moved in during the night, keeping temperatures mild. The low here was 47 F vs 27 F yesterday and airport low was 49 F vs 36 F yesterday. Image above is north view from Kitt Peak at a bit before 07:00 am MST.
The morning sounding plot from TWC shows a very layered atmosphere with saturated, or nearly saturated , conditions above 625 mb, but very dry conditions below. Morning 500 mb analysis (below from NCAR) features a weak short-wave blip over LA Basin that will zip by today with little impact, other than clouds and perhaps some virga. This will be followed late tomorrow by a more substantial wave that will bring some precipitation for the end of month.
Composite radar forecast from the 06 UTC WRF-GFS above is valid at 06:00 pm tomorrow afternoon, while the model's forecast of total precipitation through 05:00 pm on the 28th is shown below. The precipitation is forecast to occur as an AR impacts southern Arizona - at bottom is model's forecast of PW valid at 06:00 pm tomorrow evening. The 06 UTC GEFS members continue to forecast a considerable range of possible precipitation amounts at the airport - 0.15 to 1.21 ".