Many weather geeks find themselves wondering about Rosa, the mysterious caller that was never expected – was this the last gasp of an active summer monsoon, a late entry to a hurricane season with a few weeks remaining on the calendar or a harbinger of an active El Nino winter?

Rosa did add to an already wet season for Fountain Hills and much of the upper Sonoran Desert. There is a county Flood Control District rain gauge within the Fountain Hills drainage area that received more than 10 inches of precipitation as of the middle of last week.

Monsoon storms in July and August caused an estimated $80,000 in damage, mostly in downed trees, clean-up, park canopies and fencing.

Those storms also left five inches of rain in various parts of town, although flood damage was contained to street debris.

Rosa proved to be something different for Fountain Hills and Arizona in general. A hurricane over the Pacific, the storm had downgraded to a tropical depression as it crossed into Arizona. There was little wind, but plenty of moisture to be left behind. Tuesday, Oct. 2, set daily records for rainfall in Phoenix (Sky Harbor Airport) and led to wash flooding and water rescues Valley-wide.

Rainfall in the McDowell Mountains ran down the eastern slopes and into washes that backed up behind the retention dam at Golden Eagle Park. Two major washes converge in the park right behind the dam. Cloudburst Wash collects water from high in the McDowells near the new Adero Canyon Trailhead. The wash drains the southeastern reaches of the mountains and across SunRidge Canyon Golf Course before entering Golden Eagle Park.

Ashbrook Wash drains from the central area of the McDowells before crossing under Golden Eagle Boulevard into the park.

The final gasp of Rosa on Tuesday evening dropped 2.2 inches of rain on a Flood Control District monitor at the top of Cloudburst Wash. Downstream at the SunRidge Canyon Dam, a rain gauge collected another 1.7 inches that night.

Nearly three inches of rain flowed down Cloudburst Wash alone into the park. Park officials say a rain monitor in Golden Eagle Park received four inches of rain between late Sunday and early Wednesday morning.

There is a complex of ball fields in Golden Eagle Park that were designed to serve as a detention basin to protect residential and commercial areas downstream along Ashbrook Wash.

In the 25-to-30-year history of Golden Eagle Park, that detention basin has not had a real test before Rosa, but it performed as planned. Water covered nearly all of four ball fields in the park with water up to six feet deep at fences nearest the dam.

The result is that the fields and some structures in the flood basin sustained damage. The fields will likely be closed for clean-up and restoration for up to six weeks. Turf on the fields may not recover until growing season next spring and summer.

As of last week rainfall totals for the Flood Control District rain gauges in Fountain Hills had all received in excess of seven inches since January, with nearly all of that over the past three months.

Rainfall monitoring equipment along Hesperus Wash, near the far west end of town near Dixie Mine, had received 10.3 inches of rain for the year. The total at SunRidge Canyon Dam is 8.78 inches, and Fire Station #1, near downtown at Palisades Boulevard and Avenue of the Fountains, has received 7.87 for the year.

Is Fountain Hills in for more wet weather through the winter? Some forecasters are predicting an active El Nino this year, but that will be unknown until it happens.