This page provides the current weather forecast for Siwan, Bihar, India, including hourly conditions, a 10-day outlook, wind speed and direction, precipitation, UV index, and air quality - giving you everything you need to plan your day in one view.

Forecast & Methodology

The forecast data on this page is sourced from the ECMWF open-source model - a reliable global model used widely across weather services worldwide. For sailors, boaters, and mariners who need greater accuracy and higher resolution, PredictWind's proprietary forecast models deliver precision down to 1km resolution, updated multiple times daily and validated against real-world observations. Sign up free to access PredictWind's advanced forecasts.

Sailing & Marine Conditions

Siwan weather forecasts on PredictWind are optimised for sailors and boaters who need precise, reliable wind and wave data for passage planning and day sailing. PredictWind is used by ocean racers, cruising sailors, and commercial vessel operators across India and worldwide. For detailed marine conditions including wave height, swell period, and offshore wind forecasts, sign up free to access PredictWind's full marine forecast suite.

Units

Wind speed is displayed in knots - the standard unit used by sailors, weather services, and maritime authorities. Temperature is shown in degrees Celsius. Use the toggle at the top of the page to switch between Celsius and Fahrenheit. Pressure is shown in hPa, rainfall in millimetres, and air quality is available in both US and EU AQI standards.