Miscellany Sunday March 3rd

I have been away most of the day, and it has been a bit interesting this afternoon with mammatus, virga, and perhaps a few sprinkles around, as middle and upper cloudiness streamed in from the Pacific. See the 6 pm image from the campus webcam below. The surface observations on the NWS website for TUS have been bonkers for the last three days - e.g., it is showing a high yesterday of 105F for Tucson. If one goes to the daily climate area of the NWS page, it turns out high yesterday was 84F and high today was 81F. The low here yesterday was 33F so there was about a 51F diurnal range. Not bad for this time of year.

The long-range forecasts from the global models indicate some stormy weather likely across Arizona next Friday afternoon and Saturday. Above is operational ECMWF 500 mb forecast valid at 5 am MST next Saturday morning (9 March), and below is the same from the GFS. Both forecasts are quite similar over the Southwest. If these verify, a strong Pacific cold front will move across southern Arizona next Friday afternoon with showers from late Friday into Saturday. This will be our first storm event of March, and the NWS is already forecasting 60% chances for rain at the airport Friday night and Saturday. The ECMWF forecast is more progressive, with the next short wave already approaching western Canada - will be a few days before we have a good feel for how quickly the Southwest system will head toward the Plains.