CO DWR · BOCBGRCO

SOUTH BOULDER CREEK

CO DWR · BOCBGRCOLIVE

South Boulder Creek Below Gross Reservoir

BOULDER COUNTY, CO39.9383°N, -105.3480°W Updated 1 d ago

FLOW RATE

195cfs

1D 7D 30D 1YR

Flow Rate Historical Avg

MEDIAN FLOW RATE · 30 DAY

195cfs

Optimal band: 166–224 cfs

PERIOD HIGH

332cfs

PERIOD LOW

175cfs

RUNNABLE

67%

last 30 day in band

Precipitation History

Precipitation · YTD

Normal

Near-normal year

2026 to date

14.7in

≈ normal

14.68 in of precipitation so far this year — about average for this point in the season (normal 15.11 in).

YTD Total

14.7in

This year so far

Normal to Date

15.1in

30-yr average

Typical Range

10.9–19.7in

10th–90th pct YTD

Departure

-3%

vs 30-yr normal

By Month

This year

Typical range

Normal

Jan: 1.51" · normal 0.98" (0.4–1.8)

Jan

Feb: 0.95" · normal 1.09" (0.3–1.7)

Feb

Mar: 2.10" · normal 2.06" (1.1–3.0)

Mar

Apr: 2.07" · normal 3.21" (1.4–4.8)

Apr

May: 5.72" · normal 4.15" (2.3–6.3)

May

Jun: 1.96" · normal 3.11" (1.3–4.9)

Jun

Jul: 0.38" (so far)· normal 2.90" (1.5–4.3)

Jul

Aug: normal 2.85" (1.3–4.4)

Aug

Sep: normal 2.11" (0.6–3.3)

Sep

Oct: normal 1.89" (0.8–3.0)

Oct

Nov: normal 1.30" (0.7–2.3)

Nov

Dec: normal 0.91" (0.4–1.5)

Dec

Baseline 1991–2020 · Source: Open-Meteo09:46 AM

Your History · South Boulder Creek Below Gross Reservoir

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Station Location

39.9383, -105.3480

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DATA · CO DWR · NOAA · NWSUPDATED 2026-07-06 00:00 UTC

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