October Continues Dry

View looking east toward the Rincons at 5:50 am MST this morning, showing clouds on and over the mountains.

GEFS plumes for the airport from 06 UTC runs: above QPF, below Wind, and second below T. Chances for light rainfall are indicated on Friday afternoon and evening, with strong winds forecast for Friday afternoon,and distinctly cooler temperatures on the weekend.

The 06 UTC runs of the WRF-GFS at Atmo show a strong, 500 mb, closed low over Arizona at 06 UTC on the 19th (above), with light precipitation across eastern and southern Pima County through noon on Sunday (below). So, it appears that we may have some weather to watch by the end of the week, after a month with no precipitation here since the 0.01" on September 17th.

Quick Look At Milton

An IR satellite image from yesterday (above) shows Milton northwest of Yucatan, when the storm was rated as a Cat. 5 hurricane. Current morning forecast from NHC (below) indicates Milton going ashore in the Tampa area as a major hurricane late tomorrow.

Forecasts from Tropical Tidbits (above and below) consistently show most models forecasting the storm to be at Cat 3 or 4 about the time of landfall near Tampa.

October Starts Dry And Warm

View toward the Rincons at 6:40 am MST, just before sunrise this morning.

Plot of deteced CG flashes for 24-hours ending at 0733 UTC this morning (above from Atmo and Vaisala) shows absolutely no activity across the Southwest and northern Mexico - as quiet as it can be.

At 500 mb this morning (above, analysis from SPC) there is a large, oblong ridge that extends from northern California to the south end of Baja and beyond. There is an elongated trough to the east that extends from central Mexico north to southern Canada.

The plumes from the 06 UTC GEFS runs for QPF (above) for the airport indicate a slight chance for some activity at the end of next week. While the 06 UTC GFS run (below)indicates that precipitation avoids Arizona and much of the West through the 20th of Ocotber. So the dryness continues here, along with near-record high temperatures around 100 F. The last time we had a quarter inch or more rain here at the house was back on August 8th when there was 0.36 ".

September Summary

 

Early morning view looking toward the Rincons on September 1st 2024.

There was little weather to summarized during all of September. Light rain occured on only two days: 0.03" on the 15th and 0.01" on the 17th. The total of 0.04" was the second driest September here since 1999, after the driest total of zero during 2020. Wettest September occurred in 2014 with 2.78". I did not note any thunderstorms or strong winds during the month.

Nighttime Showers

View toward the Catalinas at about 3:30 am MST this early morning shows some light showers over and west of this part of the city.

Rainfall across the ALERT network (above and below for 24-hours ending at 7:00 am this morning) shows light amounts over west and northwest portions of the network. One site in the Catalinas reported nearly an inch. We had 0.01" here, as did the airport. DM reported a Trace and Atmo had no rainfall.

Plot of detected CG flashes for 24-hours ending at 1303 UTC (above, from Atmo and Vaisala) indicates some limited thunderstorm activity over eastern Pima County.

The trough at 500 mb (analysis above from SPC) this morning remains west of Tucson (there was no TWC/TUS sounding this morning), but the southwest winds are scouring w=away the low-level moisture.

Forecast below is from 06 UTC GFS model run and shows total rainfall through the end of September - if this verifies it will end up as a very dry month, since we've had only 0.04" here so far.

Showers Yesterday

View of Catalinas with heavy cloud cover at 6:30 am MST this morning.

Widespread showers occurred yesterday, with quite six sites recording over an inch of rain. Not much here at house with thunder but only 0.03" - TUS reported thunder and  0.11", while Atmo and DM had 0.04" with thunder at DM.

The plot of detected CG flashes for 24-hours ending at 0803 UTC (above from Atmo and Vaisala) indicates considerable thunderstorm activity over eastern Pima County.

At 500 mb the analysis continues to be dominated by the large, closed-low over northern California.

The morning sounding from TWC/TUS (above) is moist below 550 mb, with considerable CAPE and strong southwest winds aloft. The 12 UTC WRF-HRRR forecast for rainfall through 6:00 am tomorrow morning (below, from Atmo) indicates slight chances for showers in parts of Pima County.

Chances For Showers

Some sunrise color looking toward Redington Pass at about 6:10 am MST this morning.

The morning 500 mb analysis (above from SPC) shows a chopped up pattern over the Southwest, with a couple of weak shortwaves. The remnants of TS Ileana have apparently dissipated over the southern GoC.

The 12 UTC sounding from TWC/TUS (above, also from SPC) already has over an inch of PW, with considerable CAPE present. Winds are light below 400 mb and steering flow this afternoon would likely be from the west.

Forecast above is from the 06 UTC run of the WRF-GFS and shows PW at midnight tomorrow - note that current values in southeast Arizona are already at these values. Forecast below shows accumulated rainfall - from same model run - through 6:00 am on Tuesday morning. Highest amounts are focused from Santa Cruz and eastern Pima Counties northward toward the Rim area.