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Hi. I have a permit for Aravaipa this week. I've been in there ~half a dozen times and witnessed the foreboding aftermath of flash floods.

I know flash floods are associated with summer monsoon rains. But does anyone know whether winter rains, which I gather I'm looking at .5" per day, are also a potential concern?

Many thanks.

@SJFL
Yes. There was a recent post here where it flashed and 10 people required rescue.

2021-11-19 [ Aravaipa East Entrance ]
2018-09-12 [ Aravaipa Flash Flood & Rescues ]

Aravaipa Creek itself will certainly rise with runoff from winter storms. It did so just a few weeks ago, after that daylong rain event in the valley, rising to 1000 cfs. You can see current and historical streamflow from this gauge here https://waterdata.usgs.gov/monitoring-l ... eriod=P30D

During winter storms, I wouldn't consider the main creek to be susceptible to "immediate flash flooding" or the type of danger that you couldn't seek the safety of higher ground (no "wall of water"), but it can certainly rise to where the flow increases to the point where hiking out becomes impossible. I would be cautious about some of the narrower side canyons during a rain event as those would be more susceptible to the inescapable true "flash" flood with sheer walls and little opportunity to climb higher. But it does depend on the duration of rainfall, in addition to the amount that falls, among other factors.

The forecast this week would definitely keep me attentive. (As of Monday morning, forecast rainfall in the watershed is 1.5"-2.0" by end of Thursday). If your trip brings you back out by Wednesday, I'd probably take the risk. After Wednesday, even if subsequent rain events through the rest of the week and weekend are less significant, the ground will be saturated and surface runoff possibilities will likely increase dramatically.

@chumley
Thanks. My trip was scheduled through Thursday. I ruled that out completely. But staying until Wednesday is still causing a degree of pause. There's one particular channel on the west side that goes through a rock wall on either side for ~200-300ft. It has captured my imagination on a few different occasions for this very reason; there's no egress or scrambling up the sides.

I may just make this a long day on Tuesday and lick my metaphorical wounds (better than licking the real ones).

Appreciate you chiming in.

@SJFL
Yeah, but have you ever been on a free helicopter ride!?

@chumley
Hmmm. Not sure they are free. I know if it's National Park, yes. But BLM is a few tiers down from that designation.
No less, that's all dependent on me making it to high ground!

chumley wrote:Yeah, but have you ever been on a free helicopter ride!?

Yes, as a matter of fact, out of Aravaipa.

Forecast was for a couple hours light rain in March 2010. A pair of storms met and put heavy rain fall on the watershed into Aravaipa the last night of our 3 day trip. Normal flow is 20-40 cubic feet per second for the creek. We witnessed 1,000+ CFS which is humbling as you hear boulders rolling and crashing in the creek. Our group of 8 was lifted by DPS helicopter, aided with SAR and Sheriff from near Booger Canyon. Aravaipa is tricky to monitor current weather conditions until it is too late. The sky above is your only reference.

SJFL wrote:I'm looking at .5" per day,

By desert standards .5" is significant. Do not recall the inch forecast for our trip noted above but think it was in the .1 to .2 range. You know the canyon and have seen the past devastation of high flows.

Latest forecasts are showing the system to be more progressive, ie, not wanting to hang around very long. Doesn't look nearly as worrying as the one a few weeks ago.

@ShatteredArm
Been there, and back. I was the last one out of the West TH parking lot. Guessing no one else wanted to risk it.

Saw some big horn sheep and a mauled baby javelina (pretty tough stuff...)