AEROGRAPHER'S MATE 3 & 2 



thunderstorms, and patches of ground fog, which 

 are expected to be widely scattered In the gen- 

 eral area of the station. It Is expected there 

 is only a slight chance that they will affect 

 the station itself. Lowest ceilings and visi- 

 bilities expected in the phenomena in the vi- 

 cinity are included in the forecast. 



5. Frontal Passages (FROPA). Frontal pas- 

 sages are included in the forecast only if 

 weather or a condition of operational signifi- 

 cance is forecast. It is indicated by writing 

 FROPA preceded by a 4-figure time group 

 indicating the expected time of frontal passage 

 and is followed by an adjusted forecast. 



Additional plain language remarks may in- 

 clude the forecasted minimum altimeter setting 

 expected during the forecast period. 



A complete PLATF example follows: 



KNPA 1212 15SCT 80 BKN 15 1910 SCT VBKN 

 QHN 30.02 15Z 15BKN 80OVC 5H 2015 

 10OVC 2TRW VCNTY QNH 29.98 19Z 

 150VC 3RF 2315 TEMP 80VC IRF QNH 

 29.96 0000Z CLD FROPA 20SCT 80BKN 

 15 3215G25 QHN 30.01 GRADU 04Z-06Z 

 CLR 15 3410 QHN 30.05 



TAF— AERODROME FORECAST (FM51.Q).— 

 The code name TAF is used as a prefix to the 

 message indicating that it is an aerodrome 

 forecast, but in case of a group of such fore- 

 casts, it is only used in the heading of the 

 collective. The symbolic form of the TAF code 

 is as follows: 



TAF 



cccc 



WW 



G1G1G2G2 

 w w 



dddff/f m f m 

 N s CCh B h B h s 





CAVOK 

 (OGfGfTfTf) 



(6I c hihihitD 



(5Bh B h B h B tL) 



9i3nnn 



Groups or elements with an indicator fig- 

 ure may, unless otherwise specified, be omitted 

 from a particular message whenever the ele- 

 ments specified in the group are forecast not 

 to occur, or are not required. Groups may have 

 to be repeated in accordance with the detailed 

 instructions for each group. 



Obtain general coding instructions for this 

 and the following forecast codes by referring 

 to the Codes Manual. 



ARFOR — AREA FORECAST FOR AVIATION 

 (FM 53. ( )). — The code name ARFOR is used 

 as a prefix to the message indicating that it 

 is an area forecast. 



ROFOR — ROUTE FORECAST FOR AVIATION 

 (FM 54. ( )). — The code name ROFOR is used 

 as a prefix to the message, indicating that it 

 is a. .route forecast. 



SATELLITE OBSERVATIONS 



At most weather stations throughout the 

 United States, satellite information is provided 

 routinely by facsimile transmission of data pre- 

 viously received at satellite tracking centers. 

 If, however, you are attached to an overseas 

 station, or a ship, you will most likely be 

 involved in obtaining your own satellite in- 

 formation. 



In chapter 6 of this manual the various 

 types of satellite sensing and tracking equip- 

 ment were described. This section will discuss 

 satellite applications and expansion, terminology, 

 satellite tracking information, and instructions 

 for gridding the obtained pictures. These pro- 

 cedures provide the forecaster with an in- 

 valuable means of obtaining meteorological 

 information. The data received by this means 

 is used to supplement the more conventional 

 methods of observed data. It will, in many 

 cases, be the only method available to ob- 

 serve developing storms and their associated 

 cloud systems. 



Satellite Terminology 



In any field of science, there are numerous 

 terms, definitions, and contractions that need 

 to be understood. Without this information It 

 is extremely difficult to understand the op- 

 erational procedures and functions in the field 

 of endeavor. The list of terms, definitions, and 

 contractions presented in the following para- 

 graphs is not meant to be a complete glossary. 

 For more complete coverage you must refer 

 to the various technical manuals pertaining to 

 satellites. Figures 10-1 and 10-2 are diagram- 

 matic illustrations to aid in understanding some 

 of the terms described below. 



APT — APT stands for Automatic Picture Trans- 

 mission. It is a weather satellite system 

 that is designed to sense and transmit data 

 in the blind. 



APT TERMINAL GROUND EQUIPMENT— The 

 receiving and recording ground station that 

 is designed to receive and print the pic- 

 tures that are transmitted by a satellite 

 equipped with APT capabilities. 



176 



