A garden rain gauge log: gauge type, rim height, exposure and a fixed daily reading time

Goal

Produce a daily rainfall record for one garden in which the gauge, its position and the reading routine are stated well enough that a neighbour could compare totals, and in which every day, dry ones included, has a row.

Prerequisites

One gauge whose type is written down: a funnel-and-bottle storage gauge, an open wedge gauge, or a tipping-bucket sensor. The Met Office describes the standard daily observation as the 0900 UTC reading of a 5 inch (127 mm) storage gauge whose rim sits 30 cm above ground, and notes that the narrow funnel entrance limits debris and evaporation; the National Weather Service describes the 8-inch standard gauge, read to hundredths of an inch, and gives an exposure rule: the height of any nearby object should not exceed half its distance from the gauge. A household gauge need not meet these, but the log says how it differs.

Steps

1. Header: gauge type, orifice diameter, graduation (for example 0.2 mm or 0.01 in), rim height above ground, and a list of nearby objects with height and distance, so a reader can check the exposure rule.
2. Pick one clock time and keep it, stating the time zone and whether the clock changes with daylight saving. The reading covers the 24 h ending at that time.
3. Read at eye level with the gauge on a level surface; write the value in the gauge's graduation, "trace" when water is visible below the first mark, and "0" when dry. Never leave a blank.
4. Empty and replace the gauge after each reading; for a tipping bucket, record the display total and note any reset.
5. Flag rows: snow or hail in the funnel, a blocked or overflowing gauge, a reading taken at another time (with the actual time), and days away (the next reading is a multi-day total, marked as such).
6. Once a month, write the monthly sum and the count of flagged days in a summary row; keep the daily rows.
7. Log any move of the gauge or growth of a nearby hedge as an event: the exposure changed.

Expected result

A continuous table where a monthly total can be compared with the nearest official station with the differences in gauge, height and exposure known.

Limits and test basis

Proposed protocol; no rainfall amounts are claimed. The NWS page states that wind and turbulence near a gauge reduce the catch and that obstructions may affect it; the size of that effect for a garden gauge is not stated here. The Met Office notes that gauges block in snow and that readings during thaw need caution; this protocol flags such days rather than correcting them.