Weather Forecast; Basic Principle, Methods and Types!

In his satirical novel “Three Men in a Boat,” the author Jerome K Jerome wrote that weather forecasts are what happened yesterday or the day before, and is the opposite of what is going to happen today.

Weather Forecast

He narrated a hypothetical story when the forecast indicated heavy showers and thunderstorms and they postponed a proposed picnic and stayed inside, waiting for the rain. But it happened to be a ‘fine day’, all throughout. But those were the days of the late nineteenth century. Meteorological technology has advanced, and weather forecast has become part and parcel of human life.

Meteorology majorly focuses on weather forecasting and also includes atmospheric chemistry and atmospheric physics. Forecasting implies the prediction of some variable interest of some specified future date, based on the past and present data and the analysis of trends.

It will protect people from all kinds of threatening weather events such as tropical hurricanes, typhoons, tropical cyclones, flash floods, blizzards, high and rotating wind, snowstorms, ice, and a severe thunderstorm, tornados. Therefore, certain basic principles and methods are adapted for different types of weather forecasting.

Objective Predictions

The key principle of weather forecasting is that past patterns of weather can be indicative of future events. The first step towards this is collecting the relevant data and study the history of weather for specific areas. By the observation of the local atmospheric conditions from radar and satellite, the weather is displayed on computers, several hours in advance.

As against the earlier subjective method, the objective method is more consistent and can be revalued, studied and improved. It can also predict 6, 12, 24 or 48 hours. The method of Model Output Statistics (MOS) involves the extrapolation of specific location and time.

Long-Range Forecasting

It adopts a climatologically-oriented approach by using a broad weather picture over a period, say for about two weeks, based on forecast anomaly map that exhibits the temperature anomaly patterns.
Instead of a forecast for a particular day, it indicates the forecast trends, with a particular percent probability above the normal weather for an extended period, say for a season, like spring, winter or summer. This method relies heavily on the analogue method by the comparison of weather situations of the current with those of the previous year.

Methods and Types

1) Persistence

The principle adopted is ‘persistence ‘which says that warm summer follows warm spring and cold spring follow warm winters.  The forecasters assume that the current weather condition can show the clues for the forecast of tomorrow because the current condition will persist and will continue, unaltered.

This method could predict best in areas such as a tropical zone or an arctic zone, for which the weather patterns are easily predictable. 

2) Synoptic Weather Forecasting

This method was adopted in 1950. Synoptic implies the observation of different elements of weather about a specific time of observation. For viewing the changing pattern of weather, a metrological centre prepares a series of synoptic charts every day.

Synoptic Weather Forecasting

The centre has to collect a huge volume of data from thousands of weather stations and analysing the same. Certain empirical rules are formulated for enabling to carefully estimating the direction and rate of movement of the weather system.

3) Numerical Methods

The Numerical Weather Prediction is based on the scientific fact that the gases of the atmosphere are subjected to some physical principles. Various mathematical equations are used for developing theoretical models to study the general circulation of the atmosphere.

For formulating these equations, certain elements of weather such as temperatures, air movements, and evaporation at the ground, humidity, rain, clouds, snow and the interactions of air with the ground are taken into consideration.

4) Computer Modeling

It is the most advanced method. It relies on mathematical formulas designed as models for atmospheric and weather conditions. It maximises the accuracy of forecasting.

5) Statistical Methods

These are used along with the numerical method. It is based on the principle that future will be a repetition of the past. It takes into account, the temperature, humidity, wind velocity and direction and the amount of cloudiness.

Depending on your location or region, the weather forecast based on the most advanced technology will keep you protected from the threatening weather events. 😊

Posted in:

Liked us? Tell your friends on Facebook!


Post a Comment