Trace Of Precipitation

View looking toward the Rincons at 6:40 am MST this morning. Image at bottom shows snow up in Summerhaven at 3:00 pm yesterday. Freeze warnings in effect from the NWS for next hour and a half, and again tomorrow morning.

Many sites around the metro had a Trace or a couple of hundreths of precipitation yesterday afternoon - see MesoWest plot above for amounts through 8:00 am this morning. Here at the house we had a brief sprinkle during the early afternoon, and east winds of 30 to 40 mph during much of the day.

The 500 mb analysis this morning shows a deep trough from the Dakotas, south along the Arizona/New Mexico border, on to the end of Baja. A bit of winter has arrived.

Cold Wind Blowing

It is a nasty morning across Tucson area, with strong east winds bringing in some dust. View above from campus was at 9:15 am MST.  View at bottom, looking northeast from downtown, was at 9:20 am.

Current wind gusts (above) at 9:15 am from the Univ. of Utah MesoWest site. Below is forecast, from the 12 UTC run of the WRF-HRRR run at Atmo, showing forecast precipitation through 6:00 am tomorrow morning. Model indicates only some scattered, light precipitation across Pima County.

Current morning forecast (below, from the NWS) for the airport indicates slight precipitation chances today, followed by cold morning lows rest of week.

Brief Summary 2024

Small shower over Catalina Foothills at 4:00 pm on July 25th.

There were three months during the year with no precipitation (May, Oct, and Dec). Total rainfall for the other nine months totalled 11.78 inches. The wettest month was July with 3.72 inches.

There were 24 days with thunderstorms here at the house (as usual, I probably missed hearing thunder on a few days). Winds I estimated at 50 to 60 mph on July 18th destroyed our wooden, front gate - thus, one severe thunderstorm occurred here.

I noted no snowfall here. The coldest morning low occurred on January 9th when the temperature dropped to 21 F.

All-in-all, a pretty quiet weather year.

Unsettled Rest Of Week

Dreary view of Catalinas at 8:40 am MST this morning. Photo at bottom shows unusual ski conditions at the Capital yesterday morning.

Digging 500 mb short-wave over the Great Basin and California will impact our weather here for rest of the week.

The 06 UTC WRF-GFS forecasts dry conditions for Pima County through early Saturday morning (above); however, it predicts very windy conditions at the airport for tomorrow (below).

Current morning forecast from NWS Forecast Office (below) indicates chances for rain and snow mixed throughWednesday. So, finally a chance for some winter weather.

Winter Solistice

 
Today is the astronomical Winter Solistice, which brings us the shortest day of the year. Fair and mild conditions continue here, with no sign of winter-like weather on the horizon.

Looking Toward Christmas

View of the Rincons a bit before before 7:00 am MST, showing perfectly clear skiews - our mild and very dry weather continues.

GFS forecast from 06 UTC this morning (above - valid at 11 pm Christmas evening) shows a small, closed-low crossing the Four Corners Region, with trough extending south across the Tucson area. However, forecast of 24-hour precipitation from the same model run (below) indicates only light amounts over the northern portion of the state. Big question becomes: Will we have any precipitation here during December?

Quick Overview

View of the Catalinas at 7:30 am MST this morning (above) shows our heavily overcast skies on a fairly dreary start to the day.

IR satellite image (above for 1420 UTC) showswidespread cloudiness over the Southwest. However, the 12 UTC WRF-HRRR forecast of OLR (below valid at noon today) shows the cloudiness moving east of the Tucson area.

The long term GFS forecast (below - valid through 28 December) for total precipitation through December 28th shows dry conditions persisting over a large areaof the Southwest and northern Mexico.

Dry Fall Here

Perfectly clear skies over the Catalinas a 8:00 am MST this morning. Image at bottom, in stark contrast, shows conditions during NFL football game at Buffalo last evening.

Precipitation here for the Fall (Sep. Oct. and Nov) was only 0.37 - 0.04" in Sep and 0.33" inches in Nov, with measureable rainfall on only three days. Conditions were drier during the Fall only in 2017 (0.17") and 2020 (0.15").

Plumes for PW from 06 UTC GEFS runs (above) show dry conditions, becoming even drier during coming week.

This morning's forecast for the airport from the NWS Tucson Forecast Office (above) indicates mild and dry condtions for the coming week. The December outlook from the NWS CPC (below) indicates more of the same  for the rest of the year.