The precipitation quantity behind Hourly Rainfall Accumulation
Rate multiplied by time gives accumulated depth. This page accepts an interval no longer than 60 minutes so the result remains an hourly-interval calculation.
Hourly Rainfall Accumulation begins with constant rainfall rate, interval duration. Label each entry as measured, corrected, assumed, forecast, or derived before treating the output as a precipitation record.
Boundary and direction checks
Zero rate or zero minutes gives zero depth. Durations beyond one hour belong in a more general rate-times-time calculation.
For Hourly Rainfall Accumulation, change one input at a time and predict whether the result should rise, fall, or stay fixed. This catches reversed subtraction, percent-as-fraction errors, overlapping intervals, and misplaced unit conversions.
Limitations of the Hourly Rainfall Accumulation model
Real rainfall varies within an interval, and gauge totals may be more reliable than rate reconstruction. This calculation does not interpolate missing sub-hourly observations.
Hourly Rainfall Accumulation provides transparent arithmetic, not a weather forecast, flood warning, drainage design, drought declaration, emergency instruction, or authority to operate in hazardous conditions.
From Hourly Rainfall Accumulation, continue with the related Rain Gauge Catch Correction Calculator.
Measurement uncertainty and sensitivity
Vary the least certain Hourly Rainfall Accumulation input across a credible range while keeping other entries fixed. Report how much interval rainfall accumulation moves and whether interpretation changes.
That range is a sensitivity test, not a confidence interval. It explores selected inputs but does not capture every sampling, exposure, interpolation, model, or representativeness uncertainty affecting Hourly Rainfall Accumulation.
Depth, rate, probability, and area are different
Precipitation depth describes a layer, intensity divides depth by time, probability describes uncertainty, and areal estimates add spatial assumptions. Hourly Rainfall Accumulation should retain the quantity named in its formula.
Do not convert a point-gauge Hourly Rainfall Accumulation value into watershed volume or runoff without a defensible area model, unit conversion, and hydrologic assumptions.
Creating an auditable Hourly Rainfall Accumulation record
Save raw observations, exclusions, corrections, conversions, formula version, unrounded output, final rounding, and data-source identifiers. A reviewer should reproduce Hourly Rainfall Accumulation without guessing event or trace rules.
If a source value or method changes, issue a dated revision and retain the earlier result. Distinguish a data correction from a new Hourly Rainfall Accumulation scenario.
From Hourly Rainfall Accumulation, continue with the related Inverse-Distance Rain Gauge Estimate Calculator.
Using the result downstream
Transfer interval rainfall accumulation with its unit, accumulation period, location or area, and measurement status. Downstream work can fail quietly when a rate is used as depth or a percentage as a fraction.
One Hourly Rainfall Accumulation value summarizes one defined calculation. Trends need repeated comparable records plus documented methods for gaps, trace amounts, instrument changes, and evolving station exposure.
Working formula for Hourly Rainfall Accumulation
The page applies Depth = rainfall rate × interval minutes ÷ 60. It uses only the displayed entries, so the calculation can be reproduced without an account, hidden weather feed, or unstated coefficient.
Keep full numerical precision through Hourly Rainfall Accumulation, then round according to gauge resolution, source uncertainty, and the intended comparison rather than the number of digits available on screen.
Checked example and expected result
A constant 18 mm/h rate sustained for 40 minutes accumulates exactly 12 mm.
Reset restores that Hourly Rainfall Accumulation example. Rework it independently before substituting station, radar-derived, gridded, climatological, or scenario values.
From Hourly Rainfall Accumulation, continue with the related Precipitation Anomaly Calculator.
Collecting compatible inputs
Use a rate representative of the full entered interval. An instantaneous peak multiplied by 40 minutes is a scenario unless that rate was actually sustained.
Record site or area, start and end time, time zone, gauge type, exposure, reporting interval, precipitation phase, corrections, and quality flags with every Hourly Rainfall Accumulation result.
Interpreting Interval rainfall accumulation
The result is interval depth, not a new rate. Several interval depths can be added only when their periods do not overlap.
Compare Hourly Rainfall Accumulation outputs only when accumulation window, units, spatial support, event definition, and missing-data rules align. A numerical match can conceal incompatible records.
Common precipitation data traps
Typical Hourly Rainfall Accumulation errors include mixed millimetres and inches, local-day boundaries, duplicated intervals, missing values entered as zero, uncorrected snowfall catch, and mismatched climate periods.
Reject impossible Hourly Rainfall Accumulation field combinations instead of forcing an answer. Domain checks cannot determine whether a plausible number represents the right storm, station, basin, or period. Preserve the original precipitation code and observation resolution so later reviewers can distinguish a genuine zero from rounding, a trace, or unavailable data.
Checking the rainfall calculation
How can I verify Hourly Rainfall Accumulation?
Repeat Depth = rainfall rate × interval minutes ÷ 60 with the recorded inputs, then test the checked example and a meaningful boundary case.
Why could another precipitation source disagree?
Another Hourly Rainfall Accumulation source may use different intervals, gauges, corrections, spatial methods, thresholds, climatological periods, or rounding.
Does this page issue a weather or flood warning?
No. Hourly Rainfall Accumulation performs local arithmetic and does not replace current observations, forecasts, watches, warnings, or emergency guidance.
How should the answer be rounded?
Keep full precision within Hourly Rainfall Accumulation, then round no more finely than the source measurements and method support.