Introduction + 600 words

Meteorologists have an extremely influential and important job.  Many people check the weather first thing in the morning and may continue to check the weather throughout the day.  It is crucial that the forecast is correct, or else future forecasts may be ignored or discarded by viewers.  If the meteorologist “lies” to you with one forecast, why should you believe him or her during the next forecast?  This eventual lack of belief could lead to safety issues when warnings are ignored.  For this reason, meteorologists are under a great deal of pressure to present an accurate forecast.  Unfortunately, creating an accurate forecast is not as easy as it may sound.  An incredible amount of data and uncertainty are involved with these forecasts.  It may seem like a bit too much to ask for someone to predict the future with 100% accuracy, but nonetheless, this is what the public demands. 

Many statistics and other facts will be presented in this article to help discover the accuracy of weather forecasts.  There are limitless amounts of statistical data available to show the accuracy of the forecasts.  People’s perceptions and feelings regarding these forecasts will also be analyzed to better determine why weather forecasts are often considered to be inaccurate or invalid.  Finally, the difficulties of creating weather predictions will be discussed in order for the reader to gain a greater understanding of the field.  Hopefully the reader will realize that predicting the weather is not just a coin flip or simply looking at computer models.  

There are several possible methods of approaching this topic since there are so many different aspects involved.  It was determined that investigating the accuracy of forecasts should be the foremost goal.  This way, it will be possible to discover whether or not people’s anger and frustration with meteorologist is justified in any way.  Since forecasts are issued by countless forecasters many times a day all across the globe, there is essentially an infinite amount of statistics to show the accuracy of forecasts. 

One of the most important aspects of a weather forecast is the precipitation aspect.  For many people, it does not matter what the temperature is, they just want to know if it will rain or snow or do nothing.  In one specific study, weather forecasts for a long period of time, from August through September, were analyzed.  In this analysis, it was determined that the precipitation forecasts were extremely accurate.  Out of the 134 days observed, it only rained once when a 0% chance of rain was predicted.  The other observations show that the other forecasts (for 10%, 20%, and so on) were also quite accurate.  For example, it only rained once out of the ten times a 10% chance of rain was given.  This means it rained 10% of the time when there was a 10% chance of rain, which is about perfect.  Some other numbers were further off, most notably the 50% chance, since it rained all four times that the forecast called for a 50% chance of precipitation.  Since there were only four scenarios when a 50% chance of rain was in the forecast, it is difficult to come to a solid conclusion with that.  It would be better to look at the entire picture, which shows that the forecasts were relatively accurate.  Of note, the forecasts became slightly less accurate when the forecast was further out.  In other words, a forecast of 80% chance of rain nine days in advance is going to be much less accurate than a forecast for one or two days in advance.  There are several reasons for this lack of accuracy as time goes on, which will be discuss in latter sections of this article.   

Although precipitation is important to people, temperature also plays a vital role in people’s lives.  Similar to the precipitation observations, there is a well-defined trend of decreased accuracy as time goes on.  The forecasts for the first few days were quite accurate and consistent.  Figure 5 best shows this accuracy with several graphs indicating the amount of times the forecasted temperature was a certain amount of degrees off from the observed temperature.  During the first for forecast days, it is clear that the actual temperature was typically zero, one, or two degrees off from the predicted temperature.  This shows an incredible accuracy which many people may not be aware of.  Nonetheless, the forecast accuracy does decline with later days in the forecast.  For example, the consensus with day nine is that the forecast has little to no accuracy at all.  The predicted and actual temperatures varied by as much twenty degrees.  While these may seem very costly and potentially dangerous, it is important to realize that the forecast was ultimately accurate within a few days.  This means that if people understand the inaccurate nature of longer term forecast, then they will not be as disappointed when the forecast is relatively far off.  Instead, the focus should be on short term forecasts (within about five days) in order to receive the most accurate forecasts. 

In addition to the important aspect of accuracy, it is also vital to understand why people want to know the weather, as well as what is most important to these people.  In an expansive survey completed by the American Meteorological Society, many of these various questions were answered.