Rivermatics

USGS Streamgage 11133000

Santa Ynez River A Narrows near Lompoc, CA

Santa Ynez River A Narrows near Lompoc, CA is USGS streamgage 11133000 in California, monitoring river discharge in hydrologic subbasin 18060010. It drains a watershed of about 789 square miles. Discharge records at this site go back to 1907. Typical flow runs near 0.2 cfs in July and 17.1 cfs in April, with the higher of the two arriving in April. Rivermatics issues a daily machine-learned flow outlook for this gauge, reaching 14 days ahead, alongside daily high and low water-temperature forecasts.

View live conditions & forecast →

Gauge details

State
California
Drainage area
789 sq mi
Gauge elevation
88 ft
Subbasin (HUC-8)
18060010
Coordinates
34.63609, -120.42456
USGS site number
11133000
Records begin
1907-01-09 (119 years)
Rivermatics forecast
14-day flow outlook + water temperature

14-day flow forecast

Based on observations through for Santa Ynez River A Narrows near Lompoc, CA. 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
3.7 4.2 4.6
3.3 3.9 4.6
3 3.8 4.6
2.8 3.6 4.6
2.6 3.5 4.6
2.4 3.4 4.7
2.3 3.3 4.7
2.1 3.2 4.8
2 3.2 5.1
2 3.4 6.9
1.9 3.3 6.5
1.9 3.4 6.7
1.8 3.3 6.8
1.7 3.2 6.6

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 74 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 14.1 305.5
February 0.2 25.5 975.9
March 0.9 29.6 1,122.2
April 0.5 17.1 659.5
May 0 5.7 199.4
June 0 0.9 47.3
July 0 0.2 16.1
August 0 0 25.2
September 0 0.1 25.1
October 0 0 22.9
November 0 0.4 19.2
December 0 2.5 45.1

All values in cubic feet per second (cfs).

Common questions

When does Santa Ynez River A Narrows near Lompoc, CA normally run highest?
March, on the long-term record. The median daily flow that month is about 29.6 cfs, against 0 cfs in August, 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 Ynez River A Narrows near Lompoc, CA?
It depends on the month. In January, half of days historically fall near 14.1 cfs, with the middle 80% of days between 0 and 305.5 cfs. The month-by-month table on this page gives the full range.
How long has Santa Ynez River A Narrows near Lompoc, CA been measured?
Discharge records at USGS site 11133000 begin in 1907, about 119 years, covering roughly 9,131 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 Ynez River A Narrows near Lompoc, CA?
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. A companion model forecasts each day's water-temperature high and low. 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 Ynez River A Narrows near Lompoc, CA?
The gauge sits at 34.63609, -120.42456, in California, in hydrologic subbasin 18060010, at an elevation of about 88 feet, draining roughly 789 square miles.
Can I use Santa Ynez River A Narrows near Lompoc, CA 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.

Other gauges in this subbasin