- 🌿 Agriculture
- 💧 Irrigation
- 📰 Irrigation Leader
Forecasting Temperature, Precipitation and Evapotranspiration
CustomWeather Editorial
Published in Irrigation Leader Magazine
📅 Featured Article
⏱️ 8 min read
“Accurate temperature, precipitation, and ET forecasting is the cornerstone of efficient
water management — helping irrigation professionals make smarter decisions at the field
level.”
— CustomWeather, Irrigation Leader Magazine
The Role of Weather Forecasting in Modern Irrigation
Irrigation scheduling has long relied on historical climate norms — but in an era of increased weather variability, forward-
looking forecast data is becoming indispensable. Temperature, precipitation, and evapotranspiration (ET) forecasts give
irrigation managers the ability to anticipate soil moisture conditions, defer or accelerate watering schedules, and reduce
water waste across large-scale agricultural operations.
Understanding Evapotranspiration (ET)
Evapotranspiration — the combined loss of water through soil evaporation and plant transpiration — is one of the most
critical variables in crop water budgeting. When ET exceeds rainfall, supplemental irrigation is required. Accurate ET
forecasts allow growers to model net water demand days in advance, rather than reacting after the fact.
CustomWeather’s forecast models incorporate solar radiation, wind speed, humidity, and temperature data to compute
reference ET (ETo) values based on the FAO Penman-Monteith method — the internationally recognized standard for
irrigation planning.
KEY FORECAST VARIABLES FOR IRRIGATION PLANNING
Temperature
Min / max / hourly profiles for degree-day accumulation
Precipitation
Daily and sub-daily totals with probability of exceedance
Evapotranspiration
Reference ET (ETo) via FAO-56 Penman-Monteith
Precipitation Forecasting for Water Budget Management
Reliable precipitation forecasts — particularly at the sub-regional level — allow irrigation districts to adjust delivery
schedules, minimize runoff, and comply with water authority allocations. CustomWeather provides both deterministic and
probabilistic precipitation forecasts, giving operators confidence intervals alongside expected totals for up to 15 days
ahead.
Temperature and Degree-Day Forecasting
Accumulated growing degree days (GDD) are used to track crop development stages, pest emergence windows, and
harvest timing. Access to hourly temperature forecasts enables growers and agronomists to calculate GDD trajectories in
real time — integrating forecast data into farm management platforms and decision support systems with minimal friction.
About CustomWeather
CustomWeather is a premier provider of weather data, forecasts, and API services for enterprise clients across agriculture,
energy, aviation, and media industries. Our flexible API solutions deliver the hyperlocal weather intelligence that modern
irrigation and agri-tech platforms require.
ABOUT THIS ARTICLE
Irrigation Leader
Industry publication
Irrigation Leader is the premier magazine for
irrigation district managers and water
resource professionals across North America.
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