The effective wind speed (sss) is rounded off the nearest kilometer per
hour. The downwind distance of Zone I (xxx) is rounded off to the nearest
The cloud radius (rr) is rounded up to the next kilometer if the value is
not a whole number.
d. Disseminate the report in accordance with the unit SOP.
PART C - PREPARE A SIMPLIFIED FALLOUT PREDICTION
The simplified fallout prediction method is provided to enable small unit
commanders to make an immediate estimate of the location of the potential
fallout hazard without waiting for a detailed fallout prediction message,
NBC 3 (Nuclear) Report.
The simplified prediction method requires nuclear burst information, a
current effective downwind message, and a simplified fallout predictor.
The lateral or angular limits of a simplified fallout predictor are fixed at
40 degrees; this is in contrast to the determination of lateral limits from
current winds in the detailed method. These fixed angular limits or radial
lines are based upon climatic studies.
In most cases these fixed angular
limits are sufficient to encompass the fallout area of hazard.
Effective Downwind Message.
Use of a simplified fallout predictor requires knowledge of the effective
wind speed and downwind direction. This information is prepared by the NBCE
as an effective downwind message and is transmitted to subordinate and
adjacent units each time new upper air wind data are received. The latest
effective downwind message should always be used.
messages more than 12 hours old should not be used for fallout prediction.
The format for the effective downwind message will be a series of eight
lines preceded by the phrase Effective Downwind Message.
Effective Downwind Message
DDTTTT (local or ZULU, state which)