MATTOLE RIVER - PETROLIA (MTOC1)
Latitude: 40.31º NLongitude: 124.28º WElevation: 40 FeetForecast Type: Unofficial Location
Location: Humboldt County in CaliforniaBulletin Group: North CoastRiver Group: North Coast
Issuance Time: Apr 18 2026 at 8:43 AM PDTNext Issuance: Apr 19 2026 at 9:00 AM PDT
Action/Monitor: N/A Minor Flood: N/A Moderate Flood: N/A Major Flood: N/A

# Tabular Observed and Forecast Hydrograph Information
#
# Location: Mattole River - Petrolia (MTOC1)
#
# File Generation Time:  04/18/2026 at 08:45 AM PDT
# Data Interval:  1 Hour
#
# Most Recent Date & Time of Maximum Observed:  04/13/2026 at 08:00 AM PDT
# Maximum Observed Stage:                       12.92 Feet
# Maximum Observed Flow:                        1054 cfs
#
# Earliest Date & Time of Maximum Forecast:     04/21/2026 at 10:00 PM PDT
# Maximum Forecast Stage:                       13.71 Feet
# Maximum Forecast Flow:                        1920 cfs
#
# OBSERVED
#
# Date & Time  (Local)    Stage (Feet)     Flow (cfs)     Trend     Observed Status
# ---------------------------------------------------------------------------------
  04/13/2026 08 AM PDT           12.92           1054                Not Applicable
  04/13/2026 09 AM PDT           12.90           1031         -      Not Applicable
  04/13/2026 10 AM PDT           12.89           1020         -      Not Applicable
  04/13/2026 11 AM PDT           12.86            986         -      Not Applicable
  04/13/2026 12 PM PDT           12.86            986         0      Not Applicable
  04/13/2026 01 PM PDT           12.84            964         -      Not Applicable
  04/13/2026 02 PM PDT           12.82            942         -      Not Applicable
  04/13/2026 03 PM PDT           12.80            920         -      Not Applicable
  04/13/2026 04 PM PDT           12.80            920         0      Not Applicable
  04/13/2026 05 PM PDT           12.78            898         -      Not Applicable
  04/13/2026 06 PM PDT           12.76            876         -      Not Applicable
  04/13/2026 07 PM PDT           12.75            865         -      Not Applicable
  04/13/2026 08 PM PDT           12.74            854         -      Not Applicable
  04/13/2026 09 PM PDT           12.73            843         -      Not Applicable
  04/13/2026 10 PM PDT           12.71            821         -      Not Applicable
  04/13/2026 11 PM PDT           12.71            821         0      Not Applicable
  04/14/2026 12 AM PDT           12.69            800         -      Not Applicable
  04/14/2026 01 AM PDT           12.67            778         -      Not Applicable
  04/14/2026 02 AM PDT           12.67            778         0      Not Applicable
  04/14/2026 03 AM PDT           12.66            768         -      Not Applicable
  04/14/2026 04 AM PDT           12.65            757         -      Not Applicable
  04/14/2026 05 AM PDT           12.63            736         -      Not Applicable
  04/14/2026 06 AM PDT           12.63            736         0      Not Applicable
  04/14/2026 07 AM PDT           12.61            715         -      Not Applicable
  04/14/2026 08 AM PDT           12.61            715         0      Not Applicable
  04/14/2026 09 AM PDT           12.61            715         0      Not Applicable
  04/14/2026 10 AM PDT           12.60            704         -      Not Applicable
  04/14/2026 11 AM PDT           12.59            694         -      Not Applicable
  04/14/2026 12 PM PDT           12.59            694         0      Not Applicable
  04/14/2026 01 PM PDT           12.58            683         -      Not Applicable
  04/14/2026 02 PM PDT           12.59            694         +      Not Applicable
  04/14/2026 03 PM PDT           12.57            673         -      Not Applicable
  04/14/2026 04 PM PDT           12.57            673         0      Not Applicable
  04/14/2026 05 PM PDT           12.55            652         -      Not Applicable
  04/14/2026 06 PM PDT           12.55            652         0      Not Applicable
  04/14/2026 07 PM PDT           12.54            641         -      Not Applicable
  04/14/2026 08 PM PDT           12.54            641         0      Not Applicable
  04/14/2026 09 PM PDT           12.53            631         -      Not Applicable
  04/14/2026 10 PM PDT           12.52            621         -      Not Applicable
  04/14/2026 11 PM PDT           12.52            621         0      Not Applicable
  04/15/2026 12 AM PDT           12.51            610         -      Not Applicable
  04/15/2026 01 AM PDT           12.51            610         0      Not Applicable
  04/15/2026 02 AM PDT           12.50            600         -      Not Applicable
  04/15/2026 03 AM PDT           12.50            600         0      Not Applicable
  04/15/2026 04 AM PDT           12.49            590         -      Not Applicable
  04/15/2026 05 AM PDT           12.49            590         0      Not Applicable
  04/15/2026 06 AM PDT           12.48            580         -      Not Applicable
  04/15/2026 07 AM PDT           12.48            580         0      Not Applicable
  04/15/2026 08 AM PDT           12.47            570         -      Not Applicable
  04/15/2026 09 AM PDT           12.47            570         0      Not Applicable
  04/15/2026 10 AM PDT           12.47            570         0      Not Applicable
  04/15/2026 11 AM PDT           12.47            570         0      Not Applicable
  04/15/2026 12 PM PDT           12.46            560         -      Not Applicable
  04/15/2026 01 PM PDT           12.47            570         +      Not Applicable
  04/15/2026 02 PM PDT           12.47            570         0      Not Applicable
  04/15/2026 03 PM PDT           12.47            570         0      Not Applicable
  04/15/2026 04 PM PDT           12.47            570         0      Not Applicable
  04/15/2026 05 PM PDT           12.47            570         0      Not Applicable
  04/15/2026 06 PM PDT           12.46            560         -      Not Applicable
  04/15/2026 07 PM PDT           12.46            560         0      Not Applicable
  04/15/2026 08 PM PDT           12.46            560         0      Not Applicable
  04/15/2026 09 PM PDT           12.46            560         0      Not Applicable
  04/15/2026 10 PM PDT           12.44            540         -      Not Applicable
  04/15/2026 11 PM PDT           12.45            550         +      Not Applicable
  04/16/2026 12 AM PDT           12.45            550         0      Not Applicable
  04/16/2026 01 AM PDT           12.45            550         0      Not Applicable
  04/16/2026 02 AM PDT           12.45            550         0      Not Applicable
  04/16/2026 03 AM PDT           12.45            550         0      Not Applicable
  04/16/2026 04 AM PDT           12.44            540         -      Not Applicable
  04/16/2026 05 AM PDT           12.44            540         0      Not Applicable
  04/16/2026 06 AM PDT           12.44            540         0      Not Applicable
  04/16/2026 07 AM PDT           12.43            530         -      Not Applicable
  04/16/2026 08 AM PDT           12.43            530         0      Not Applicable
  04/16/2026 09 AM PDT           12.43            530         0      Not Applicable
  04/16/2026 10 AM PDT           12.43            530         0      Not Applicable
  04/16/2026 11 AM PDT           12.43            530         0      Not Applicable
  04/16/2026 12 PM PDT           12.43            530         0      Not Applicable
  04/16/2026 01 PM PDT           12.43            530         0      Not Applicable
  04/16/2026 02 PM PDT           12.42            520         -      Not Applicable
  04/16/2026 03 PM PDT           12.41            510         -      Not Applicable
  04/16/2026 04 PM PDT           12.42            520         +      Not Applicable
  04/16/2026 05 PM PDT           12.41            510         -      Not Applicable
  04/16/2026 06 PM PDT           12.41            510         0      Not Applicable
  04/16/2026 07 PM PDT           12.40            500         -      Not Applicable
  04/16/2026 08 PM PDT           12.40            500         0      Not Applicable
  04/16/2026 09 PM PDT           12.40            500         0      Not Applicable
  04/16/2026 10 PM PDT           12.39            490         -      Not Applicable
  04/16/2026 11 PM PDT           12.39            490         0      Not Applicable
  04/17/2026 12 AM PDT           12.39            490         0      Not Applicable
  04/17/2026 01 AM PDT           12.38            479         -      Not Applicable
  04/17/2026 02 AM PDT           12.37            469         -      Not Applicable
  04/17/2026 03 AM PDT           12.38            479         +      Not Applicable
  04/17/2026 04 AM PDT           12.37            469         -      Not Applicable
  04/17/2026 05 AM PDT           12.36            458         -      Not Applicable
  04/17/2026 06 AM PDT           12.37            469         +      Not Applicable
  04/17/2026 07 AM PDT           12.36            458         -      Not Applicable
  04/17/2026 08 AM PDT           12.36            458         0      Not Applicable
  04/17/2026 09 AM PDT           12.36            458         0      Not Applicable
  04/17/2026 10 AM PDT           12.35            448         -      Not Applicable
  04/17/2026 11 AM PDT           12.35            448         0      Not Applicable
  04/17/2026 12 PM PDT           12.36            458         +      Not Applicable
  04/17/2026 01 PM PDT           12.36            458         0      Not Applicable
  04/17/2026 02 PM PDT           12.36            458         0      Not Applicable
  04/17/2026 03 PM PDT           12.35            448         -      Not Applicable
  04/17/2026 04 PM PDT           12.35            448         0      Not Applicable
  04/17/2026 05 PM PDT           12.35            448         0      Not Applicable
  04/17/2026 06 PM PDT           12.35            448         0      Not Applicable
  04/17/2026 07 PM PDT           12.34            438         -      Not Applicable
  04/17/2026 08 PM PDT           12.34            438         0      Not Applicable
  04/17/2026 09 PM PDT           12.33            428         -      Not Applicable
  04/17/2026 10 PM PDT           12.33            428         0      Not Applicable
  04/17/2026 11 PM PDT           12.33            428         0      Not Applicable
  04/18/2026 12 AM PDT           12.33            428         0      Not Applicable
  04/18/2026 01 AM PDT           12.32            419         -      Not Applicable
  04/18/2026 02 AM PDT           12.32            419         0      Not Applicable
  04/18/2026 03 AM PDT           12.32            419         0      Not Applicable
  04/18/2026 04 AM PDT           12.32            419         0      Not Applicable
  04/18/2026 05 AM PDT           12.32            419         0      Not Applicable
  04/18/2026 06 AM PDT           12.32            419         0      Not Applicable
  04/18/2026 07 AM PDT           12.32            419         0      Not Applicable
  04/18/2026 08 AM PDT           12.31            409         -      Not Applicable
#
# FORECAST
#
# Date & Time  (Local)    Stage (Feet)     Flow (cfs)     Trend     Forecast Status
# ---------------------------------------------------------------------------------
  04/18/2026 09 AM PDT           12.31            409                Not Applicable
  04/18/2026 10 AM PDT           12.31            409         0      Not Applicable
  04/18/2026 11 AM PDT           12.31            409         0      Not Applicable
  04/18/2026 12 PM PDT           12.31            409         0      Not Applicable
  04/18/2026 01 PM PDT           12.30            400         -      Not Applicable
  04/18/2026 02 PM PDT           12.30            400         0      Not Applicable
  04/18/2026 03 PM PDT           12.30            400         0      Not Applicable
  04/18/2026 04 PM PDT           12.30            400         0      Not Applicable
  04/18/2026 05 PM PDT           12.30            400         0      Not Applicable
  04/18/2026 06 PM PDT           12.30            400         0      Not Applicable
  04/18/2026 07 PM PDT           12.29            390         -      Not Applicable
  04/18/2026 08 PM PDT           12.29            390         0      Not Applicable
  04/18/2026 09 PM PDT           12.29            390         0      Not Applicable
  04/18/2026 10 PM PDT           12.29            390         0      Not Applicable
  04/18/2026 11 PM PDT           12.29            390         0      Not Applicable
  04/19/2026 12 AM PDT           12.29            390         0      Not Applicable
  04/19/2026 01 AM PDT           12.29            390         0      Not Applicable
  04/19/2026 02 AM PDT           12.28            381         -      Not Applicable
  04/19/2026 03 AM PDT           12.28            381         0      Not Applicable
  04/19/2026 04 AM PDT           12.28            381         0      Not Applicable
  04/19/2026 05 AM PDT           12.28            381         0      Not Applicable
  04/19/2026 06 AM PDT           12.28            381         0      Not Applicable
  04/19/2026 07 AM PDT           12.28            381         0      Not Applicable
  04/19/2026 08 AM PDT           12.27            372         -      Not Applicable
  04/19/2026 09 AM PDT           12.27            372         0      Not Applicable
  04/19/2026 10 AM PDT           12.27            372         0      Not Applicable
  04/19/2026 11 AM PDT           12.27            372         0      Not Applicable
  04/19/2026 12 PM PDT           12.27            372         0      Not Applicable
  04/19/2026 01 PM PDT           12.27            372         0      Not Applicable
  04/19/2026 02 PM PDT           12.27            372         0      Not Applicable
  04/19/2026 03 PM PDT           12.26            364         -      Not Applicable
  04/19/2026 04 PM PDT           12.26            364         0      Not Applicable
  04/19/2026 05 PM PDT           12.26            364         0      Not Applicable
  04/19/2026 06 PM PDT           12.26            364         0      Not Applicable
  04/19/2026 07 PM PDT           12.26            364         0      Not Applicable
  04/19/2026 08 PM PDT           12.26            364         0      Not Applicable
  04/19/2026 09 PM PDT           12.25            355         -      Not Applicable
  04/19/2026 10 PM PDT           12.25            355         0      Not Applicable
  04/19/2026 11 PM PDT           12.25            355         0      Not Applicable
  04/20/2026 12 AM PDT           12.25            355         0      Not Applicable
  04/20/2026 01 AM PDT           12.25            355         0      Not Applicable
  04/20/2026 02 AM PDT           12.25            355         0      Not Applicable
  04/20/2026 03 AM PDT           12.24            346         -      Not Applicable
  04/20/2026 04 AM PDT           12.24            346         0      Not Applicable
  04/20/2026 05 AM PDT           12.24            346         0      Not Applicable
  04/20/2026 06 AM PDT           12.24            346         0      Not Applicable
  04/20/2026 07 AM PDT           12.24            346         0      Not Applicable
  04/20/2026 08 AM PDT           12.24            346         0      Not Applicable
  04/20/2026 09 AM PDT           12.24            346         0      Not Applicable
  04/20/2026 10 AM PDT           12.23            338         -      Not Applicable
  04/20/2026 11 AM PDT           12.23            338         0      Not Applicable
  04/20/2026 12 PM PDT           12.23            338         0      Not Applicable
  04/20/2026 01 PM PDT           12.23            338         0      Not Applicable
  04/20/2026 02 PM PDT           12.23            338         0      Not Applicable
  04/20/2026 03 PM PDT           12.23            338         0      Not Applicable
  04/20/2026 04 PM PDT           12.24            346         +      Not Applicable
  04/20/2026 05 PM PDT           12.26            364         +      Not Applicable
  04/20/2026 06 PM PDT           12.34            438         +      Not Applicable
  04/20/2026 07 PM PDT           12.46            560         +      Not Applicable
  04/20/2026 08 PM PDT           12.62            725         +      Not Applicable
  04/20/2026 09 PM PDT           12.89           1020         +      Not Applicable
  04/20/2026 10 PM PDT           13.41           1584         +      Not Applicable
  04/20/2026 11 PM PDT           13.49           1673         +      Not Applicable
  04/21/2026 12 AM PDT           13.56           1751         +      Not Applicable
  04/21/2026 01 AM PDT           13.60           1796         +      Not Applicable
  04/21/2026 02 AM PDT           13.62           1818         +      Not Applicable
  04/21/2026 03 AM PDT           13.64           1841         +      Not Applicable
  04/21/2026 04 AM PDT           13.64           1841         0      Not Applicable
  04/21/2026 05 AM PDT           13.65           1852         +      Not Applicable
  04/21/2026 06 AM PDT           13.66           1864         +      Not Applicable
  04/21/2026 07 AM PDT           13.66           1864         0      Not Applicable
  04/21/2026 08 AM PDT           13.67           1875         +      Not Applicable
  04/21/2026 09 AM PDT           13.67           1875         0      Not Applicable
  04/21/2026 10 AM PDT           13.67           1875         0      Not Applicable
  04/21/2026 11 AM PDT           13.67           1875         0      Not Applicable
  04/21/2026 12 PM PDT           13.67           1875         0      Not Applicable
  04/21/2026 01 PM PDT           13.67           1875         0      Not Applicable
  04/21/2026 02 PM PDT           13.67           1875         0      Not Applicable
  04/21/2026 03 PM PDT           13.66           1864         -      Not Applicable
  04/21/2026 04 PM PDT           13.66           1864         0      Not Applicable
  04/21/2026 05 PM PDT           13.67           1875         +      Not Applicable
  04/21/2026 06 PM PDT           13.67           1875         0      Not Applicable
  04/21/2026 07 PM PDT           13.68           1886         +      Not Applicable
  04/21/2026 08 PM PDT           13.69           1898         +      Not Applicable
  04/21/2026 09 PM PDT           13.70           1909         +      Not Applicable
  04/21/2026 10 PM PDT           13.71           1920         +      Not Applicable
  04/21/2026 11 PM PDT           13.71           1920         0      Not Applicable
  04/22/2026 12 AM PDT           13.70           1909         -      Not Applicable
  04/22/2026 01 AM PDT           13.68           1886         -      Not Applicable
  04/22/2026 02 AM PDT           13.65           1852         -      Not Applicable
  04/22/2026 03 AM PDT           13.61           1807         -      Not Applicable
  04/22/2026 04 AM PDT           13.57           1762         -      Not Applicable
  04/22/2026 05 AM PDT           13.54           1728         -      Not Applicable
  04/22/2026 06 AM PDT           13.51           1695         -      Not Applicable
  04/22/2026 07 AM PDT           13.48           1662         -      Not Applicable
  04/22/2026 08 AM PDT           13.45           1628         -      Not Applicable
  04/22/2026 09 AM PDT           13.42           1595         -      Not Applicable
  04/22/2026 10 AM PDT           13.39           1562         -      Not Applicable
  04/22/2026 11 AM PDT           13.36           1529         -      Not Applicable
  04/22/2026 12 PM PDT           13.33           1497         -      Not Applicable
  04/22/2026 01 PM PDT           13.30           1464         -      Not Applicable
  04/22/2026 02 PM PDT           13.27           1431         -      Not Applicable
  04/22/2026 03 PM PDT           13.22           1377         -      Not Applicable
  04/22/2026 04 PM PDT           13.19           1345         -      Not Applicable
  04/22/2026 05 PM PDT           13.15           1303         -      Not Applicable
  04/22/2026 06 PM PDT           13.11           1260         -      Not Applicable
  04/22/2026 07 PM PDT           13.13           1281         +      Not Applicable
  04/22/2026 08 PM PDT           13.07           1218         -      Not Applicable
  04/22/2026 09 PM PDT           13.03           1176         -      Not Applicable
  04/22/2026 10 PM PDT           13.00           1145         -      Not Applicable
  04/22/2026 11 PM PDT           12.98           1122         -      Not Applicable
  04/23/2026 12 AM PDT           12.97           1110         -      Not Applicable
  04/23/2026 01 AM PDT           12.95           1088         -      Not Applicable
  04/23/2026 02 AM PDT           12.94           1076         -      Not Applicable
  04/23/2026 03 AM PDT           12.92           1054         -      Not Applicable
  04/23/2026 04 AM PDT           12.90           1031         -      Not Applicable
  04/23/2026 05 AM PDT           12.89           1020         -      Not Applicable
#
# NOTE 1: Stages are rounded to the nearest hundredth (.01) of a foot.
# NOTE 2: Flows are rounded to the nearest (1) cfs.
# NOTE 3: Trends are determined using hourly change in unrounded stage and flow.
# NOTE 4: Maximum Values are determined using unrounded stage and flow.