AEROGRAPHER'S MATE 3 & 2 



here is that they are complete weather ob- 

 servations. The synoptic code, therefore, is 

 a code by which synoptic weather observations 

 are communicated. Synoptic weather observa- 

 tions are, in turn, plotted on synoptic charts 

 and then analyzed. The result is that a syn- 

 optic analysis or an overall view of the 

 weather is obtained. 



Synoptic observations are taken at periodic 

 intervals the world over. Since the intervals 

 coincide — that is, since they are taken at the 

 same time all over the world — the plotted and 

 analyzed synoptic charts afford a worldwide 

 "snapshot" of the weather situation. 



The symbolic form of message used by 

 land stations for synoptic reports is as follows: 



mil Nddff VVwwW PPPTT NhCLACMCH 

 TdTdjajpjp (P0P0P0P0) (7RRjj) (8N s Ch s h s ) 

 (9SpSpSpS p ) 



Groups in parentheses are optional. 



ME TAR — AVIATION ROUTINE WEATHER 

 REPORT (FM 15.( )). — This code is used pri- 

 marily outside the United States for the same 

 purpose the Aviation Weather (Airways) code 

 is used within the United States. The informa- 

 tion in the two codes is similar but the format 

 is different. When you need specific information 

 regarding it, refer to the Codes Manual. 



SPE CI — AVIATION SELECTED SPECIAL 

 WEATHER REPORT (FM 16.( )). — The code 

 form is the same as used for the METAR, 

 except the term SPECI is used in the heading 

 In place of METAR. 



SHIP — SURFACE REPORT FROM SHIP IN 

 FULL FORM (FM 21. ( )). — The ship synoptic 

 code, FM 21 .( ) full form, is the basic ship syn- 

 optic code in use by fleet weather units and 

 other U.S. ships (Navy or merchant). The con- 

 tents of the code are very similar to those of 

 the land station synoptic code; the only differ- 

 ences are those in reporting position, time, 

 and certain information relating to the sea. 



The symbolic form of the ship synoptic code, 

 full form, follows: 



SHIP 99L a L a L a Q c LoL L Lo YYGGi w 

 Nddff VVwwW PPPTT 

 NhCLhCMCH D s v s app . 

 (7RRjj) (8N s Ch s h s ) 

 (^SpSpV (OT s T s T d Td) 

 (lTVT w T w t T ) (2I S E S E S R S ) 

 (3P W P W H W H W ) (dwd w P w H w H w ) 

 ICE followed by plain language or by 

 (C2KDire) 



SHIP — SURFACE REPORT FROM SHIP IN 

 ABBREVIATED FORM (FM 22.( )). — Your use 

 of this code will be only to decode and plot it. 

 The first seven groups are identical with those 

 of SHIP FM 21. ( ). It is used by many mer- 

 chant and foreign ships; it is not encoded by 

 Navy ships. 



SHRED — SURFACE REPORT FROM SHIP IN 

 REDUCED FORM (FM 23.( )). — This code form 

 is suitable for use by ships which do not have 

 tested instruments and which are requested to 

 report because of their location in sparse data 

 areas. It is not used by Navy ships. 



SPESH — SPECIAL WEATHER REPORT 

 FROM SHIP (FM 26. ( )). — This code is used 

 by ships for reporting special weather con- 

 ditions. Criteria for this report include specific 

 changes in wind speed and/or direction, fog, 

 precipitation, pressure, state of sea, and cer- 

 tain weather phenomena. 



Forecast Codes 



Along with surface observations, the 

 Aerographer's Mate must be able to encode 

 and decode the forecast conditions expected 

 at his station, along the airways, and at other 

 stations. The Navy terminal forecast code 

 (PLATF) is disucssed in detail, and a brief 

 description on several of the other codes uti- 

 lized in forecasts is covered in the following 

 paragraphs. 



TERMINAL FORECAST CODE (PLATF).— 

 The "Plain Language Terminal Forecast Code" 

 (PLATF) is the code form used by specified 

 Naval Weather units for transmission coding 

 of their terminal forecast. 



The form and content of the code have been 

 designed to include the necessary meteorologi- 

 cal information for the safe operation and flight 



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