Rivermatics

USGS Streamgage 09486500

Santa Cruz River at Cortaro, AZ

Santa Cruz River at Cortaro, AZ is USGS streamgage 09486500 in Arizona, monitoring river discharge in hydrologic subbasin 15050302. It sits on the Santa Cruz River, alongside 7 other gauges Rivermatics tracks on the same river. It drains a watershed of about 3,503 square miles. Discharge records at this site go back to 1939. Typical flow runs near 40.5 cfs in July and 38.3 cfs in April, with the higher of the two arriving in July. Rivermatics issues a daily machine-learned flow outlook for this gauge, reaching 14 days ahead.

View live conditions & forecast →

Gauge details

State
Arizona
Drainage area
3,503 sq mi
Gauge elevation
2,124 ft
Subbasin (HUC-8)
15050302
Coordinates
32.35072, -111.09588
USGS site number
09486500
Records begin
1939-10-01 (87 years)
Rivermatics forecast
14-day flow outlook

14-day flow forecast

Based on observations through for Santa Cruz River at Cortaro, AZ. Each day carries a median estimate and the band the model expects the flow to fall within — not a single number to plan against. Forecasts are re-issued daily; see the live screen for the current outlook.

Forecast daily mean discharge in cubic feet per second, by date
Date Low p10 Expected p50 High p90 Range
54.6 97.3 399
64.2 227 1,565
42.6 77.6 281
37.2 54.3 99.3
35 47.4 73
33.8 44.5 63.2
33.8 43.8 62.6
33.6 43.8 67.4
33 43.3 66.7
32.4 42.5 59.4
33 43.1 77.2
33 43.8 80.3
32.1 42.7 67.7
31.6 41.7 61.3

All values in cubic feet per second (cfs). Estimates only — do not use them for navigation or for any safety, rescue, or emergency decision.

Typical flow by month

Long-term daily discharge percentiles from the USGS record (up to 87 years of data), averaged within each month. These describe the historical normal range — they are not a forecast and not today's reading.

Historical monthly discharge percentiles in cubic feet per second
Month Low p10 Typical p50 High p90 Range
January 0 44.9 80.7
February 0 42 80.9
March 0 40.2 71.4
April 0 38.3 60.5
May 0 36.8 57.6
June 0 35 57.3
July 0 40.5 233.9
August 0 46.1 261.3
September 0 44.2 96.3
October 0 40.3 64.2
November 0 42.5 68.3
December 0 44.8 75.3

All values in cubic feet per second (cfs).

Common questions

When does Santa Cruz River at Cortaro, AZ normally run highest?
August, on the long-term record. The median daily flow that month is about 46.1 cfs, against 35 cfs in June, the lowest month. These are historical normals for the date, not a forecast and not today's reading.
What is a normal flow for Santa Cruz River at Cortaro, AZ?
It depends on the month. In January, half of days historically fall near 44.9 cfs, with the middle 80% of days between 0 and 80.7 cfs. The month-by-month table on this page gives the full range.
How long has Santa Cruz River at Cortaro, AZ been measured?
Discharge records at USGS site 09486500 begin in 1939, about 87 years, covering roughly 9,130 days of published daily values. The long record is what makes the monthly percentiles on this page meaningful.
Is there a flow forecast for Santa Cruz River at Cortaro, AZ?
Yes. Rivermatics trains a machine-learned model — a temporal-fusion transformer — on this basin's observed flows, weather, and snowpack, and issues a daily flow outlook reaching 14 days ahead: a median estimate inside a confidence band, not a single number to bet on. Every forecast is scored against days the model never trained on, and that track record is published on the live gauge screen. Open live conditions to see the current outlook.
Where is Santa Cruz River at Cortaro, AZ?
The gauge sits at 32.35072, -111.09588, in Arizona, in hydrologic subbasin 15050302, at an elevation of about 2,124 feet, draining roughly 3,503 square miles.
Can I use Santa Cruz River at Cortaro, AZ data for flood or safety decisions?
No. Rivermatics provides estimates, not guarantees, and the readings and forecasts here may be delayed, inaccurate, or wrong. Do not use them for navigation or for any safety, rescue, or emergency decision. Check the National Weather Service and USGS directly, and use your own judgment.

Upstream and downstream on the Santa Cruz River

Every gauge Rivermatics tracks on this river, ordered by drainage area — upstream first. See the Santa Cruz River in full.

Other gauges in this subbasin