AEROGRAPHER'S MATE 3 & 2 



the WMO regions there are, in addition, also 

 national differences. The WMO regions are as 

 follows: 



WMO Region I — Africa. 

 WMO Region II — Asia. 

 WMO Region III — South America. 

 WMO Region IV — North and Central America. 

 WMO Region V — Southwest Pacific. 

 WMO Region VI — Europe. 

 WMO Region IX — German Democratic Repub- 

 lic (East Germany). 



Codes are the lifeblood of meteorological 

 work; without them there could not be a sys- 

 tem of observing and disseminating weather in- 

 formation as it exists. Codes permit the 

 translation of a wealth of meteorological and 

 oceanographic information into concise and com- 

 prehensive reports consisting of numbers and, 

 in some instances, contractions. Moreover, codes 

 break the language barrier and make possible 

 international cooperation in the area of mete- 

 orology and its associated services. 



Codes are also the elements with which 

 Aerographer's Mates 3 and 2 come in daily 

 contact. A great responsibility is placed upon 

 you when entrusted to encode or decode mete- 

 orological and oceanographic information. You 

 can and should accept this responsibility by 

 learning and knowing the meteorological and 

 oceanographic codes well. To accomplish this 

 task you must study the following references: 



1. International Meteorological Codes (Year) 

 and Worldwide Synoptic Broadcasts, NAVAIR 

 50-IP-ll (hereinafter referred to as the Codes 

 Manual). 



2. The appropriate Federal Meteorological 

 Handbooks (FMH) pertaining to codes. 



Contractions 



The sheer bulk of data required for a clear 

 presentation of environmental conditions neces- 

 sitates the use of contractions in order to 

 reduce the length of messages. Contractions 

 are used in observations to facilitate the re- 

 porting of all significant phenomena. 



Some examples of contractions will be seen 

 In this chapter; many more will be found In 

 FMH No. 1. 



SURFACE OBSERVATIONS 



This section of the chapter deals with types 

 of surface observations (aviation and synoptic) 

 that are most commonly used in meteorology, 

 along with some of the methods used to pre- 

 pare the observations for coding. Observations 

 are recorded on meteorological form MF1-10 

 at shore stations and NWSC form 3140/8 at sea, 

 using the instructions contained in FMH No. 1. 



Aviation weather observations are classi- 

 fied according to their purpose. The informa- 

 tion included In each type of observation depends 

 on the time of the observation, and the operating 

 conditions and procedures of the reporting sta- 

 tion. 



Record Observations 



Record observations are taken at scheduled 

 hourly intervals. The record observation is a 

 complete observation and contains the informa- 

 tion for the following weather elements: ceilings; 

 sky; visibility; weather; obstruction to vision; sea 

 level pressure; temperature; dew point; wind di- 

 rection, speed, and character; altimeter setting; 

 and appropriate entries in the remarks column. 



The entry in column 1 of MF1-10 and NWSC 

 form 3140/8 for a Record observation is "R". 



Special Observations 



A Special observation is taken to report 

 significant changes in weather elements. Special 

 observations normally include the following ele- 

 ments: ceiling, sky condition, visibility, weather 

 phenomena, wind and wind shifts, altimeter set- 

 ting, and remarks. A Special observation for 

 a tornado, waterspout, funnel cloud, or runway 

 conditions may be reported as a single element 

 special. When a Special observation coincides 

 with a record observation, all elements re- 

 quired for the Record observation are observed, 

 logged, and transmitted. 



The proper entry in column 1 of MF1-10 

 and NWSC form 3140/8 for a Special observa- 

 tion is "S"; when the time coincides with a 

 Record observation the proper entry is "RS". 



Special observations are taken in accord- 

 ance with the instructions contained In FMH 

 No. 1. 



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