Chance For Showers

View of the Catalinas at a bit after 7:00 am MST this morning.

Yesterday was another very quiet day across Arizona. Plot of detected CG flashes for 24-hours ending at 0903 UTC (0203 am) from Atmo (above) shows only a couple of flashes along the New Mexico border in Cochise County. Another day with no rain here at the house. However, today's forecast for the airport (below) indicates fairly good POPs for rain through Thursday.

Note that today is the first day of astronomical Fall, however, I track Fall as Sep, Oct, and Nov.

Meanwhile, to our south, Polo has rapidly intensified  into a hurricane and is now rated Category 5 at 145 kts - a very spectacular change since yesterday's post. The forecast track for Polo - below from NHC - indicates the storm moving to southwest of Baja by Sunday morning - if this track verifies, the storm should trigger a significant GoC surge of moisture into southern Arizona.

Eastern Pacific Active

View looking toward the Rincons at 5:50 am MST this morning.

While the eastern Pacific is active (see below), things have been very quiet across the Southwest. There was no rainfall reported across the ALERT Network yesterday, and no rain here at house since the 16th. The plot of detected CG flashes for 24-hours ending at 0803 UTC (0103 am) - above from Atmo - indicates a couple of isolated flashes around the south end of the Rincons yesterday afternoon. I checked radar and there was a brief, isolated echo in that area.

Plumes for QPF from 09 UTC runs at SPC (above) indicate activity picking up tomorrow for a couple of days. The current morning forecast for the airport (below) keeps things pretty low key through Wednesday.

An IR image from the eastern Pacific at 14 UTC (below) shows newly formed TS Polo near the southern Coast of Mexico. Storm with large, very cold, cloud shield to the west is Odalys, which remains a TS. The forecast track for Polo is shown below. After a loop to the south the forecast indicates strengthening into a moderate hurricane, as it tracks northeastward. If the forecast proves accurate the storm should trigger a strong surge of moisture into the Southwest late Saturday into Monday. We will keep a close watch on how this storm actually evolves.

Significant Rain Event

Storms along the foothills around 5:40 pm MST yesterday afternoon.

ALERT reports for 24-hours ending at 8:00 am this morning show almost complete coverage, with numerous sites over an inch. Note the report over three inches at northwest corner of the network! Here at house we had thunder with gusty winds of 40 mph or so and 0.64" of rain. The rain fell off and on from before 6:00 pm into the early morning hours of today.

The 12 UTC runs of NBM indicate activity for the coming week staying to our east (below).

Dreary Morning

View of the Catalinas at 8:45 am MST this morning shows it to be a somewhat dreary morning,

Yesterday was quite suppressed, with only two ALERT sites reporting 0.04" - above. Was a dry day here at the house yesterday.

Hazards map from SPC for today (above) shows very large areas under Flash Flood Watches and also Heat Advisories.

The plumes for TUS QPF (above from SPC at 09 UTC) continue to show activity for the airport, especially today. The current forecast for the airport is shown below.

Numerous Showers Yesterday

Showers moving into foothills at 6:00 pm MST yesterday afternoon.

Rains were widespread across the ALERT Network (above) with many reports above half an inch. There are also two sites with more than two inches. Here at house we only had 0.10". There were two severe wind reports near the airport, with a gust to 68 mph and a pole down.

Current NWS morning forecast for airport (below) keeps high POPs today and tomorrow (below).

Increasing Chances For Showers

View of Cbs along north slopes of the Catalinas at 3:00 pm MST yesterday afternoon.

Below are the ALERT Network reports for 24-hours ending at 8:00 am this morning, Fourteen sites reported 0.04", while a site near Tubac had 0.12". Again, there was nothing here at the house.

The NWS has issued a Flash Flood Watch for today (above). POPs for the airport are high through Wednesday (below).

Bit Of Rain

Pre-sunrise color looking east toward the Rincons this morning.

Rainfall was scattered across the ALERT Network during the 24-hours ending at 9:00 am MST this morning (above). There were some heavy amounts mixed in, with one site reporting over two inches. Here we had some afternoon sprinkles, with only 0.02" left in the gauge. The NWS forecast for the airport (below) continues to call for increased storm activity during the next few days.

Mostly Suppressed Again

Bit of color over the Catalinas about 6:00 am MST this morning.

Plot of detected CG flashes (above - from Atmo for 24-hours ending at 0233 am) shows only a few flashes over the Catalinas in eastern Pima County. Only six sites across entire ALERT Network reported rain (below for 24-hours ending at 7:00 am), all far removed from main metro area. Nothing here again.

Graphic from the NWS (above) shows POPs for today. The morning forecast for the airport is shown below through Monday night, with chances for showers picking up as new week begins.

Another Dry Day

Pre-dawn color over Redington Pass at about 5:30 am this morning.

There were very few lightning CG flashes detected over Arizona yesterday - above plot from Atmo is for 24-hours ending at 0903 UTC (2:03 am MST). No ALERT sites recorded rainfall - below for 24-hours ending at 8:00 am this morning.

NBM 12 UTC runs (above) forecast a swath of precipitation from Mexico to the Dakotas through 12 UTC on Monday morning. Current morning forecast from the NWS for the airport through the weekend (below), indicating fairly low POPs.

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.