• Hurricane Igor

Special Considerations during Tropical Storm Season

StormGeo Shipping Insights, July 2016
By Aaron Dehart Head of Profession, EOV & Jim Sigafoose Head of Profession, Performance

Tropical storm season (June 1 – November 30 in the Northern Hemisphere), is a welcomed challenge for StormGeo route analysts. The challenge of providing advice to avoid severe weather conditions leads to more time consuming voyages and in depth report analysis keep staff busy. Here is a look at how this process is conducted through StormGeo’s End-of-Voyage analysis (EOV) and claim support teams.

Safety is paramount when a vessel is forecast to encounter severe conditions while steaming. Evasive measures such as vessel drifting, speed reduction and route alterations are common in order to avoid interaction with potentially damaging conditions associated with tropical storms. Additional factors such as ship type, speed, load condition and position relative to the storm are taken into consideration when providing recommendations to avoid tropical systems. StormGeo has developed specialized container, bulker, tanker and RORO vessel servicing teams to handle the various vessels which are underway at any given time in order to ensure the highest level of service during potentially dangerous situations.

A lesser known, but also important part of tropical season is determining the performance speed of a vessel which had to take action in order to avoid a tropical storm. This pertains to the End of Voyage reports where Speed assignments and calculated fuel consumption are important to ensure vessels adhere to agreed upon charter party terms signed prior to a vessel's voyage. The End of Voyage Department is tasked with resolving which periods of steaming should be included and which periods should be excluded in a performance speed assignment when a vessel is in the vicinity of a tropical system. This undertaking can add significant time to the analysis of a route while not missing any details on a given voyage. Additional challenges during peak tropical season include increased vessel message traffic and the number of underway vessels. The increased message traffic and volume of underway ships place an additional responsibility on the analyst to work efficiently and quickly while sorting out complex voyage details associated with tropical season.

An objective and well done report reduces the number of disputes which may be associated with a vessel which is not meeting the speed or fuel consumption description outlined in the initial charter party agreement. StormGeo End of Voyage employees have a wealth experience and resources to ensure the most accurate and fair performance speed and fuel consumption are assigned for all vessels; while keeping the performance analysis turnaround time to a minimum.

Further to the issue of establishing an accurate performance speed to a vessel that has been influenced by a tropical system, as mentioned care must be taken that a fair evaluation is carried out.

For example, a vessel may be recommended to reduce speed in order to allow a tropical storm to safely clear ahead of the vessel’s track. It could be the case that while doing this the vessel is sailing in c/p defined good weather conditions outside of the influence of the storm. In that case it would be necessary to exclude that portion of the voyage from a good weather performance analysis since safety dictated that the vessel operate outside the terms of the c/p speed and consumption warranty.

 reduced RPM in good weather to avoid Nepartak                     VESSEL PROCEEDING A REDUCED SPEED DUE TO TROPICAL STORM FROM 04TH JULY / 0400 UTC

Similarly it may be the case that a vessel is recommended to increase speed (and hence consumption) for a period in order to clear safely ahead of a tropical storm. Again, it would be necessary to exclude such a period from a performance evaluation so as not to unfairly penalize the vessel for the increased consumption of fuel as a result. This can be seen in the following report where the vessel is sailing in BF/4 conditions, good weather by most charter party descriptions. However, the consumption will not be in line with the charter party description as the ship’s RPM’s are increased for storm avoidance, and the day should therefore be excluded from good weather calculations.


StormGeo carefully scrutinizes each situation to ensure a proper and equitable assessment of a vessel’s performance speed and consumption is carried out, outside any influence of a tropical system. The challenge of providing advice to avoid severe weather conditions and ensuring the safest route is a priority for all at StormGeo.

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