Waterlands
San Mateo C Bl Junction Box A Dam1 nr Hillsborough River
USGS · 11162737
SAN MATEO C BL JUNCTION BOX A DAM1 NR HILLSBOROUGH RIVER
USGS · 11162737LIVE

SAN MATEO C BL JUNCTION BOX A DAM1 NR HILLSBOROUGH

SAN MATEO COUNTY, CA37.5560°N, -122.4177°W Updated 22 hr ago
FLOW RATE
0cfs
Flow Rate Historical Avg
MEDIAN FLOW RATE · 30 DAY
0cfs 100.0% vs avg
Precipitation History

Precipitation · YTD

Normal

Near-normal year

2026 to date

14.7in

≈ normal

14.73 in of precipitation so far this year — about average for this point in the season (normal 14 in).

YTD Total

14.7in

This year so far

Normal to Date

14.0in

30-yr average

Typical Range

6.6–23.6in

10th–90th pct YTD

Departure

+5%

vs 30-yr normal

By Month

This year
Typical range
Normal
Jan: 3.28" · normal 3.95" (0.8–8.5)
Jan
Feb: 5.76" · normal 4.26" (0.5–8.3)
Feb
Mar: 0.94" · normal 3.24" (0.5–6.7)
Mar
Apr: 3.84" · normal 1.64" (0.3–2.6)
Apr
May: 0.77" · normal 0.76" (0.0–1.8)
May
Jun: 0.14" · normal 0.15" (0.0–0.4)
Jun
Jul: 0.00" (so far)· normal 0.02" (0.0–0.0)
Jul
Aug: normal 0.03" (0.0–0.0)
Aug
Sep: normal 0.08" (0.0–0.2)
Sep
Oct: normal 0.93" (0.0–2.9)
Oct
Nov: normal 2.00" (0.6–3.9)
Nov
Dec: normal 3.74" (0.3–6.9)
Dec
Baseline 19912020 · Source: Open-Meteo10:30 PM
Your History · SAN MATEO C BL JUNCTION BOX A DAM1 NR HILLSBOROUGH

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Station Location

37.5560, -122.4177
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DATA · USGS · NOAA · NWSUPDATED 2026-07-08 00:00 UTC
Site #11162737·USGS

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