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The previous sections have outlined areas where efficiencies could be made in an operational environment. These involved office layout and staffing, observing systems, the use of workstations, warning dissemination systems, validation of forecasts and the need for public education programs. Something that has not really been addressed in the chapter so far and which probably demands examination is what forecasters actually do during a cyclone episode. What should be the operational strategy of a TCWC? The scope of this question must be sufficient to cater for the situation of both the forecaster, sitting alone in a small forecasting office, or a member of a forecasting team in a major TCWC. With a cyclone approaching, can forecasters turn to this chapter and gain from it information on what they should be doing?
One could subtitle this section "What to do when you are operational - on the bench - in charge - responsible". The following points are intended to serve as general guidance for a TCWC forecaster - a checklist of what to do.
Your government may be able to justify a forecasting error made with the best intentions and based on all available information a lot easier than trying to justify an error resulting from a lapse in procedures or indecision that could point to some degree of incompetence. Forecasters should be fully aware of the operational plan and adhere to it.
Have available a checklist of duties on a time schedule. You can then manage your available time more effectively. There is nothing worse than not being able to make a warning deadline, particularly if the delay was avoidable.
Once upon a time all a cyclone forecaster needed to know was how to keep the pencil sharp. Technology is changing all that and a forecaster must be absolutely familiar with the intricacies of all operational equipment, especially computer based workstations. Although these systems are designed with robustness in mind, one can never eliminate the possibility of "crashing" a system, and this is most likely to occur in a pressure situation. A forecaster will need to be able to quickly restore a system in such an event (assuming the problem is not hardware related). Pre-season familiarisation with equipment is essential.
Refer to Chapter 2 of this manual for techniques to use in assessing cyclone formation. If the suspect area has the potential to produce gales within 12 to 24 h, act. Warnings of gales developing with this order of lead time will assist shipping operations and counter disaster groups. If the system does not develop, then the warning can be readily cancelled, but as long as there is a recognised potential for cyclone formation, there should be appropriate alerts to users. It is easier and often a lot less painful to cancel a warning for a system that did not develop than to issue a reduced lead time warning for a developing system.
Make sure each position fix is consistent with previous fixes. It may be necessary to revise past locations in the light of more recent data. Always have a consistent track. Know the location errors associated with each technique used (Refer to Section 3.2 for position analysis). Make sure you have processed all available information.
Refer to Chapter 2 on intensity change techniques and Chapter 3 on track prediction techniques. Be aware of the techniques and of their shortcomings in your region. Forecasters need to know which techniques to favour in certain circumstances. This ability may be acquired after years of working in a TCWC and it may be called "experience", but if it can be documented, this useful knowledge can be passed on to others.
If time permits, keeping a log or diary (for example, of reasons for adopting certain policies, or reasons for discounting a certain track prediction technique or for positioning the centre in a particular location) can be of significant benefit. By documenting everyone's reasoning, someone (your cyclone specialist for example) can post-analyse why things went right or maybe astray. Progress through this process can then be made in an operational environment. Forecasters may be squandering vast amounts of experience and knowledge by not documenting their actions. If it is possible, assign a period to the forecaster (at the end of the shift maybe) for annotating the log.
In a warning message, always give the cyclone position corresponding to the warning issue time or at the most, 1 h before. For example the last firm cyclone fix may have been at 2100 UTC, prior to the next warning issue time of 2400 UTC. That warning should carry an extrapolated cyclone position for either 2300 UTC or 2400 UTC. The error in the extrapolation will be small overall, but it will have the effect of enhancing the timeliness and the credibility of the whole warning message. Users do not respond well to apparently "hours old" information. Also, make sure the warning carries the time of the next warning issue, so that users will be in no doubt when the next information update will be (and adhere rigorously to that schedule).
Forecasters should be aware of when a cyclone is starting to pose a threat to a community. Local research into the location of cyclones 24 h prior to impacting a community can lead to the identification of "danger zones" to alert forecasters as to what may be occurring. Strike probability routines also allow an assessment of the degree of threat being posed by a particular cyclone. (Refer to the section on probability forecasts in Chapter 7).
It is easy to make mistakes when working under the stress of a tropical cyclone event - simple mistakes such as putting in the wrong issue time, or the wrong date, or an incorrect position coordinate, or even leaving out an important piece of information about the cyclone. Simple, avoidable errors and omissions like these can have the effect of eroding credibility amongst users. Make it a policy to double check every warning before releasing it. If possible get another staff member to check the warning text, as a fresh eye will usually pick up an error much more effectively. Time taken at this stage for one final check will pay dividends.
If there is a major change likely to the forecast (for example a cyclone changing direction, a significant relocation of centre position or sudden intensification), know the key outside people who need to be contacted and pre-empt the issue of the next warning by informing them of the changes as soon as possible. Time saved at this stage can be invaluable.
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