Some new snow this morning at Forest Lakes in the Rim Country.
This morning's forecast from NWS Forecast Office - an active three days on tap. Note that the airport is under a winter weather advisory starting tomorrow. The two graphics below are a bit confusing, since one has Tucson in the advisory area and one does not. Consider the above as the current situation.
Morning charts and model forecasts in next post.
Bit of morning sun hitting campus about 7:40 am MST today. Down at bottom is snow stake in Forest Lakes, Arizona, which is in the Rim Country east of Payson.
In fact, the ensembles forecast a high probability of snow mixed with the rain at the airport (below) Tuesday night into Wednesday morning.
The 06 UTC runs of the WRF-GFS at Atmo are indicating very strong winds at the airport Monday afternoon (above), as second short wave approaches. The same forecast runs indicate light snow accumulations in the far east and south portions of the metro area during Monday night (below), which could bring some hazardous driving conditions, especially on two lane highways such as 83 south toward Sonoita, and 86 west toward Sells, as well as 90 south toward Sierra Vista. Will follow up re these possibilities tomorrow.
Sun breaks through to highlight the University a bit after 5:00 pm MST yesterday. Denver (bottom) had a very fiery sunset yesterday.
Showers yesterday totaled mostly less than a quarter of an inch, except on west side of Tucson Mountains, with much of the main metro area mostly missing out. Couple of sprinkles here but nothing measurable. ALERT (above) and MesoWest (below) observations are for 24-hours ending at 6:00 am this morning.
Now I'll wait for next system and hope for a better outcome here at the house. At 500 mb another closed low is forecast to cross Arizona Sunday (above) with trailing system re-enforcing the Southwest trough by Tuesday (below).
The 06 UTC GEFS plumes for temperature are shown second below. Cold Sunday through Tuesday but then a rapid warming rest of week. Looks like another morning here with temperatures down in the 20's Wednesday.
Chaotic skies this morning before sunrise, after light showers that occurred a bit before and after midnight. Here at the house there was rain, but as of now it totaled only 0.05". Barley enough to wet our bone-dry ground. Radar (2nd tilt) from 0635 am MST (below) shows heaviest showers off to our southeast and some light showers/sprinkles out to the west.
Rainfall reports through 6:00 am: ALERT north above; ALERT S below; and metro area (bottom, from MesoWest). Amounts were heaviest to our south and southeast - only one report of half inch (0.51") down near Madera Canyon. All-in-all somewhat of a fizzle given the forecasts of past few days.
Another great sunrise here in Tucson. Our first precipitation event of 2021 is imminent and much anticipated, since there has only been 0.01" of rain here at house since December 11th.
Happened to catch a view of a BurlingtonNorthernSantaFe train clipping through Flagstaff this morning (bottom).
Yuma has had a thunderstorm during the night and now has about 0.40" of rainfall. Plot of detected CG flashes for about the last 6 hours (below, from Atmo and Vaisala) shows quite a bit of activity north end GoC into southwest Arizona, and also with the closed low west of Baja.
The 500 mb low (above) has moved about as forecast yesterday and is currently well southwest of San Diego. The 1430 UTC GeoColor image below (from CIRA at Colorado State) shows considerable middle and high clouds (gray shades) from the low across Baja and into western Arizona and California deserts. The blue shades are low clouds and the orange areas are the city lights of Arizona and California.
Second below is forecast rain amounts from the 12 UTC WRF-RR run this morning - WRF amounts are down by around an inch relative to yesterday. Note that the WRF picks up the ominous Tucson donut hole, probably due to downslope, low-level winds.
Regardless, I look forward to seeing what the gauge out in our yard catches!
Partly cloudy with some color at 8:00 am MST this morning.
Today we will see increasing clouds and also some gusty winds from the east to southeast. Forecast above from the 06 UTC run of the WRF-GFS at Atmo shows 10-m winds at noon today. Forecast for temperature at the airport from the 06 UTC GEFS ensemble system (below) indicates this is our last really mild day, and we'll see cooling for rest of week
At 500 mb this morning a strong, closed low is centered over Nevada (above), with very strong winds over 100 kt on northwest side of the low. The 250 mb chart for same time (below) shows strong north-northeast jet from Montana to central California coast. This jet will pull the low southwestward to be off of Baja tomorrow. The low is forecast to go far enough west to allow it to pick up subtropical moisture and bring it into Arizona, setting the stage for a significant precipitation event.
Forecast above (also from 06 UTC WRF-GFS) is for composite radar echoes valid at 9:00 pm tomorrow night - large area of rain indicated for Pima County and also strong echoes, perhaps thunderstorms, out around Yuma. Forecast totals for precipitation through midnight on Thursday night (below) are impressive, as are the QPF plumes from the 06 UTC GEFS (bottom). Many to most of the model runs are forecasting over an inch of rain at the airport. If all this is reasonably accurate, we're looking at the best rains here at low elevations in many months!
Brilliant blues skies over the Catalinas again, this morning of the Martin Luther King Holiday. However, model forecasts continue to indicate that there will be a good chance for a rainy end of the week.
Second image from bottom shows a pink sunrise on this past Saturday morning.
I have been alerted by Morris Webb, of Albuquerque, that the image at bottom does NOT show the lights of Los Angeles, as I have often stated. Rather the view from Mt. Hamilton is of the lights of San Jose and San Francisco at the north end of the Santa Clara Valley. Thanks to Morris for his message
