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Rainfall gauge nr Farnham

Farnham, Surrey, GU9 9ND
Awaiting readings
—
Current rate
Updated 28 min ago
Awaiting a complete set of last-hour readings (3 of 4 received). Recorded rainfall so far: 0.0 mm. A complete last-hour rate is not yet available. October has 10.2 mm recorded so far. Observations are incomplete, so a comparison with usual rainfall up to today is unavailable.
—
mm/hr
awaiting readings
Unavailable
0
1 hour
mm
75% coverage
Observed total
0
6 hours
mm
95% coverage
Observed total
0.4
24 hours
mm
98% coverage
Observed total
10.4
7 days
mm
99% coverage
Observed total
10.2
Oct
usual to date: 25.2mm (estimated)
Observed total
388.1
2026
mm
Observed total

Coverage shows valid readings received out of the expected 15-minute observations. Gaps may understate rainfall and are not treated as dry weather.

Water fills show relative rainfall, not flood risk. Hourly cards use rainfall intensity; 24 hours uses recorded wet-day percentiles; longer totals use estimated seasonal pace for the elapsed period. Grey means there is insufficient coverage or history for a comparison.

9.9 mm on 7 Oct 2026 was the wettest day at this gauge since 2 Jun 2026 and in the top 9.3% of 505 rain days in this gauge's 2-year record.
Ground Wetness
Antecedent conditions based on recent rainfall
20
Normal
of 100
DryNormalDampWetSaturated
10.3mm
3d
10.4mm
7d
19.9mm
14d
23.5mm
30d
Ground conditions are normal. Moderate rainfall would be absorbed before significantly affecting rivers. Antecedent Precipitation Index with exponential decay. Decay rate adjusted for transitional conditions (K=0.92).
24h Weather Forecast
Precipitation -12h / +12h
Rainfall → River Response
Detecting lag...
Shows how rainfall at this gauge translates to river level changes over time. The lag between peak rain and peak river helps predict downstream impact.
Events on this timeline About El Niño

Choose a layer to see recorded events alongside the chart.

Events in this view (0)
    How nearby rivers respond to rainfall here
    Estimated response characteristics based on distance and catchment
    Based on historical data analysis and proximity. This is not an official flood forecast or warning.
    What happened after similar rainfall?

    Explore recorded river changes and compare events after drier or wetter weeks.

    Comparisons use complete past observations, including events with little rise. Ground wetness is estimated from preceding rainfall.

    Recent Rainfall Events
    Detected storm events from continuous readings
    Historical Context
    Records, anomalies, and comparisons
    Nearby River Gauges
    Nearby Rain Gauges

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    Monthly Overview
    Monthly rainfall totals with historical normal range

    Farnham gets about 770 mm of rain a year on average (wettest month November, 91 mm; driest May, 46 mm). That is 34% drier than the UK as a whole, which averages 1,163 mm a year. Source: Met Office HadUK-Grid 1991–2020 (5 km grid), 2.1 km away. Average rainfall: HadUK-Grid v1.3.2, Met Office. Contains public sector information licensed under the Open Government Licence v3.0.

    Nearby storm overflows
    Water-company event-duration monitors within 3 km of this rain gauge
    Loading nearby overflows…

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    Location

    Reference
    280826TP

    Source
    Environment Agency

    Coordinates
    51.226121, -0.774805

    County
    Surrey

    Data from
    -

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