Sprinkles

Views of the Catalinas and Rincons (top and bottom) at about 6:00 am MST this morning.

ALERT data for 24-hours ending at 7:00 am this morning. Only isolated reports mostly in or near the mountains - nothing in the metro area again. Although it does appear that we had a Trace here yesterday.

Dry Here

Struggling cumulus over the Catalinas around 2:00 pm MST yesterday afternoon (8 September). Down at bottom is view of Rincons this morning a bit before 6:00 am.

Plot of detected CG flashes for 24-hours ending at 1403 UTC (7:03 am) shows Pima County storm-free. In fact, there has yet to be any rainfall here at house during September. - Quick Correction - I neglected to post on Labor Day when there was 0.03" during light, pre-dawn showers.

The 06 UTC GFS 500 mb forecast (above - valid at 18 UTC on Sept 16th) shows Arizona west of a huge anticyclone centered over the Southeast. There is an elongated trough over the Northwest. The GFS forecast of precipitation through this same period is shown below, with decent amounts stretching north through western New Mexico and eastern Arizona.

AM Showers Labor Day

Heavy cloud cover at 7:15 am MST Labor Day morning. 

There were scattered light showers around the area as per NWS radar 2nd tilt scan at 7:15 am (above).  There were no CG flashes detected across Pima Count yesterday.

Rainfall plot from CSU (below - thru 7:30 am our time) shows numerous reports of light amounts across eastern Pima County - 0.03" in the gauge here. TUS noted 0.01"; while DM had a Trace and Atmo reported no amount.

Outlook for the week for Tucson and Sierra Vista (above - from NWS webpage). Current morning forecast for the airport below.

Isolated Showers Yesterday

View a bit after sunrise this morning, looking toward Redington Pass at about 6:15 am MST.

Only isolated, light showers yesterday here and there across the ALERT Network - plot above for 24-hours ending at 8:00 am this morning. Nothing here at the house.

The current NWS forecast for the upcoming Labor Day holiday weekend.

TPW analysis at 15 UTC this morning, showing the three Pacific hurricanes - from west to east - Lowell, Karina, and Marie. Note that the very high PW contents east of Marie did not make it into southern Arizona. Image below shows moonrise last evening at 11:15 pm.

Summer 2026

CG flash east of Rincsons early am on July 28th.

Summer is over and the following is a brief summary of my observations here at the house.

August rainfall was 2.19", which is a fairly typical amount - month was mostly dry with 1.30" occurring on last day of month.  Since 1999 the range in August amounts has been from 0.29" (2025) to 6.47" (2008). The summer total here was 3.89" with a summer range from 1.51" (2013) to 10.89" (2021). I noted thunderstorms on 21 days during the summer. Several of those produced gusts of 40 to 50 mph (my estimates). I did not notice for several days, but the storms on August 19th or 23rd took down a fairly large limb on a Palo Verde tree in our back yard. So that was a localized severe gust, and I may have under-estimated the winds that day. We will now watch to see what Fall has in store for us.

High PW Over GoC

View toward Redington Pass at 6:30 am MST this morning.

 There were isolated showers around the ALERT Network during the 24-hours ending at 8:00 am this morning (above). Amounts were generally light, except for 1.30" amount near Green Valley. That looks suspect, but there was a small and strong cell in the area yesterday - so it can not be easily dismissed.

Plumes for QPF (above - from o6 UTC GEFS runs) indicate an active two days on tap. The POPs for TUS from same runs (below) are very high today and tomorrow. 

The plot of TPW (below) at 14 UTC shows very high values over GoC and parts of Sonora, but with Hurricane Marie moving westward, it is not clear whether the high PW air will be able to push into southern Arizona.

Tropical Storm Marie Develops

View of very heavy rain that is obscuring almost everything except a bit of campus at 11:15 am MST yesterday morning.

Rainfall reports across the ALERT Network for the 24-hours ending at 6:00 am this morning. We had a total amount here of 1.30" for the event; the airport had 0.62"; and DM reported 1.01". The observations from Atmo appear suspect with, a very low total of only 0.16".

The GEFS plumes for QPF (above, from the 06 UTC runs) indicate an active week for the next three days. The POPs for TUS (below) are also high next several days.

Tropical Storm Marie developed far south of Baja early this morning. The IR image above from 1430 UTC shows Marie (right) and Cat 4 Hurricane Karina far to the west. The current NHC forecast for Marie (below) keeps the storm far offshore, as it becomes a hurricane. The forecast track keeps Marie far southwest of Baja, and it is not clear what, if any, impact the storm will have on the Southwest US.

Heavy Rain Event

Bit of a lightning flash over western Catalinas at about 5:30 am MST this early morning. Image at bottom shows heavy rain showers along the foothills about 5:15 am.

Plot of detected CG flashes (from Atmo) for 24-hours ending at 7:00 am (above) shows the early morning lightning occurred mostly west of main metro area. However, vivid flashes and thunder were active here before sunrise.

Rainfall occurred mostly over northern portions of the ALERT Network (above plot for 24-hours ending at 7:00 am). We had 0.74" (mostly from 4 to 6 am); TUS had 0.37"; DM reported 0.29"; and Atmo noted only 0.06". Note there were four sites with more than an inch.

Current morning forecast for the airport (above); while below shows the QPF forecast for today from the Weather Prediction Center at NCEP.