Weather and climate are important factors deciding the growth of any crop. Meteorologists and seed technologist view the weather as a dominant element influencing yield and acreage behaviour of crops. The meteorological inputs, unlike other inputs such as land, labour, high-yielding variety (HYV) seeds, fertilizers, pesticides, etc. is a direct input in seed production. The functional relationship between weather and yield is as much complicated as the term ‘weather’ itself. Occurrence of abnormal weather episodes during the growing season or during critical development stages may hamper growth processes resulting in yield reduction. Optimum temperature is the balanced heat requirement for the crop since lower or higher temperature results in abnormal effect of the crop growth. When the temperature goes below the minimum or the base level it is said that the physiology will be reduced or even nil. Similarly, when the temperature goes above the maximum the metabolic activity is enormous leading to the scorching or burning effect. The range of wavelength is a part of electromagnetic spectrum of the radiant energy which includes short wave, x-rays and g rays, long radio waves. The electromagnetic spectrum comprises of U-V, visible, IR wavelength which together transmits 90% of energy. Precipitation in any forms say rainfall, snow, fog, mist, dew, etc is important for the crop growth in relation to the seed production. Because the requirement of water for a plant growth is fulfilled naturally by precipitation. However, the effect is more contemplated in tropical countries like India. Amount of water vapour present in the atmosphere at a given time to the same atmosphere under saturation is termed as relative humidity. The VPD namely Vapour Pressure Deficit which is the difference between the pressure exerted by an atmosphere at a given condition to the same at atmosphere at hundred per cent saturation. That means the VPD is the prime cause for the transpiration of the crop plants. Seed production in efficient manner is a challenge in today’s context in correlation to weather parameters. The sowing window is to be adjusted accordingly so that all the growth phases coincides with favourable weather conditions and the crop is having an opportunity to produce quality seeds. The farm shall have wind breaks and shelter belts to enable suitable microclimate for crop production. Weather cannot be changed but managed by knowing before its occurrence termed as weather forecasting.