Why are long range forecasts less reliable?
Long range forecasts are sometimes less reliable for a couple of reasons. Long range forecast issued by EC or TWN are based on computer generated numerical models. The models are based on a variety of weather elements, high level circulation patterns and moisture as well as precipitation patterns and pressure fields. In addition there is climatology ingested into the model outputs. This simply means the models look at conditions that occurred over the past 30 years and then project those conditions for that specific date into the future. The atmosphere is very dynamic and is in constant motion. The long-range models are issued twice daily, morning and late evening, and can change considerably from the previous day. When this computer generated guidance changes it results in the long-range forecast seeming to be less reliable. What is a ‘meteorological bomb’? A meteorological bomb is an intense cyclone or low pressure system. The central pressure of the BOMB must fall 24 millibars or mo
