FORECASTING MISCONCEPTIONS
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METEOROLOGIST JEFF HABY
Many students have a conception that forecasting is a subject that is learned and mastered perfectly. The student
may believe they will be taught an "exact" method of forecasting. After learning this "method" they will be able
to produce wonderful forecasts. This however is not the case due to the fact that weather is CONSTANTLY changing and
there is a high degree of uncertainty in all weather data. Each weather situation requires a slightly and
sometimes drastically different set of forecasting methods. The developed forecasting method is unique to
each individual.
The more one learns about the atmosphere, the more one realizes there is even more to learn. This statement can be
applied to any subject area and to life in general. Knowledge is infinite. The public may not understand how
complex the atmosphere really is. It is a miracle the forecast models do as well as they do. Of course, the
more one knows about the atmosphere and practices forecasting the better they will become at forecasting.
Forecasting the weather will never be an exact science. Even a student with a meteorology degree
may not know how to forecast. The meteorologist must have skills in weather pattern recognition, skills at deciphering
interactions of many variables (3-D view of atmosphere), have an almost instant interpretation of model and analysis
charts and a strong WILL to learn from forecast failures. A strong will is a powerful asset.
One half of forecasting is art. Artistic talents such as thinking in 3-D and playing the interaction of weather
elements in the mind (e.g. how thermal advection
changes the trough ridge pattern) are difficult for some people
but can be developed through daily practice. In fact, the most advanced forecasters see a comprehensive 4-D view
of the atmosphere in the mind, with time being the 4th dimension. Advanced thinkers can view an analysis chart
or forecast panel and see it go into motion in their mind. They can also look at one analysis chart and be able to
see how the others should look.
Almost all universities lean toward forecasting as a pure science. For example, how many places can you get a
Bachelor of ARTS in meteorology? Actually, pure forecasting is both a science and an artistic talent. The science
behind forecasting is equations. From these equations meteorologists can explain the physical processes that occur
in the atmosphere. The art behind forecasting is using the mind to put the atmospheric processes together
and explain what is happening. Each of the following are artistic talents that apply to forecasting:
(1) Weather pattern recognition
(2) Putting a forecast into words that are understandable to the general public
(3) Seeing the atmosphere in 3-D in the mind
(4) Visualizing atmospheric processes in your mind (putting atmosphere into motion)
(5) Correlating thermodynamic indices with the expected weather
(6) Making weather graphics
(7) Intuition (the 6th sense)
(8) Experience (no college course can do the forecasting for you).
The best forecasters use BOTH their scientific knowledge and artistic talents to forecast the weather. Those
that don't use both become POOR forecasters.
Another misconception is not having enough time to forecast. The forecast process can be "streamlined" in several ways.
First, having the data already in front of you saves much time. It takes time to jump from image to image on a computer
and it is difficult to compare charts if they are not seen at the same time. This is where the benefit of a "map room"
comes into play. An ideal map room would have all the forecast model, analysis charts, relevant skew-T diagrams, moving
satellite and radar images on separate screens, and NWS text data printed out and up to date. It is a blessing to have
someone working for you that can print out these data each day and post them on the wall.
A second way of saving time is to keep up with the weather each day. If a couple of days proceed without studying
any weather data, a person is going to have to spend time catching up on what is currently happening with the weather.
This is synonymous to going to the restroom for 10 minutes during the middle of the movie. Once you take your seat
after 10 minutes, someone will have to catch you up to the missed scenes and vital information may be lost that adds
to the movies understanding. The atmosphere is one continuous movie that must be studied frame
by frame as it changes.
Understanding an analysis chart requires these three components:
(1) Being able to interpret all the different isopleths
(2) Interpreting any number given on the analysis chart
(3) Knowing the physical processes in the atmosphere that produce the analysis chart.
For beginning forecasters it is a benefit to draw on the analysis and model charts.
For example: Drawing over the 500 mb height contours to pick up
shortwaves, drawing in areas of
warm and cold air advection, and drawing
over frontal positions on the surface and upper level charts. Drawing on charts develops
the 3-D view of the atmosphere and enhances important meteorological processes occurring in
each level of the atmosphere. Having instant interpretation of weather data will make the forecast process
quicker. Getting to this stage of quick interpretation requires much practice.
Another forecasting mistake comes about by making the forecast process "too easy" or "too hard". The "too easy"
forecasters spend only a couple of minutes looking at weather data to develop a forecast. Much of their forecast
is based on general forecasts made from the NWS or other forecasters. Sometimes this may need to be done if one
is in a time crunch, but keep in mind that these forecasts will not make one a better forecaster. The ultimate
misconception is to think forecasting is easy.
Then we have the "too hard" forecaster. These forecasters analyze the weather so critically that they are unable
to come to a forecast consensus. When studying weather data, there will be discrepancies in the
MOS, model and
analysis data. The "too hard"
forecasters spend so much time studying these discrepancies that they become
counterproductive. If a forecaster has plenty of time then this forecast method is perfect, but if time is
lacking, their method needs to be streamlined. The best way to overcome some of these problems is to know which
MOS and forecast model is the best for a particular day. Being a "too hard" forecaster in the long run will be
better than a "too easy" forecaster for obvious reasons.
As a general statement, meteorologists have a different outlook on
severe weather than the general public.
Meteorologists and weather geeks run toward severe weather while the generally public wants to get out of
the way of severe weather. As an example, two of my meteorology friends and I were watching the approach of
hurricane Bret to the Texas coast. My friends were highly disappointed that the eye of the storm was going
to move into an unpopulated region of the Texas coast (between Brownsville and Corpus Christi). The Weather
Channel had a crew reporting on hurricane Bret as it moved toward the coast. My friends were disappointed the
Weather Channel was not going to be able to film destruction due to the hurricane missing the populated areas.
Of course, most people are glad the hurricane moved into an unpopulated area. I have counted numerous times
when meteorologists I know wished for a severe weather outbreak or winter storm outbreak. Meteorologists tend
to be less fearful of severe weather since they know more of what to expect from it.
Some people in the general public do not understand that "weather" can not be forecasted beyond a week with
reasonable accuracy. This applies to the person who calls a broadcast meteorologist and asks "How is the
weather going to be on my wedding next month" or "How will the weather look for my vacation
to Florida in two weeks". In these cases, climatological forecasting would help answer
these questions.
A forecast's accuracy is only as good as the precision desired. For example, a predicted high of between 50 and
60 ° F will have a much better chance of verifying than a predicted high of exactly 55 ° F. It is important to
develop a method of forecast verification that is both fair to you and the people you are forecasting for. In the
example in this paragraph, a high of between 54 and 56 ° F (mid-50's) is a sufficient compromise.
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