Chapter 11 — WATCH ROUTINES (CONTINUED) 



weather messages, filing, plotting weather charts, 

 preparing local weather messages for transmis- 

 sion, or relaying information from the teletype 

 messages to the forecaster and pilots. 



Identifiers 



The first line of all weather messages con- 

 tains the heading (e.g., SAC A MKPB 041500) 

 which generally includes the type of data (SA- 

 Aviation Hourlies), the geographical location 

 (CA-Caribbean), originator of the message 

 (MKPB-Barbados), the date (04-4th day of the 

 month), and time of the message (1500-in GMT). 



Sometimes the message heading may include 

 a one- or two-digit number between the geo- 

 graphical location and originator (e.g., ABUS 

 5 KWBC 061000 or SMUS 72 KWBC 101400). 

 A single digit differentiates between two or more 

 bulletins of similar contents from the same 

 geographic area, while two digits usually in- 

 dicate the WMO (World Meteorological Organ- 

 ization) block number of stations contained in 

 a weather bulletin. 



There is an extensive number of data and 

 geographical designators used in weather mes- 

 sage headings and you are not expected to 

 memorize them all. Familiarization with many 

 of them will occur once you start working in 

 the weather office. Included in appendix IX of 

 this manual is a listing of some examples used 

 in weather message headings. For a complete 

 listing refer to AWSM 105-2 Vol. 1 or Inter- 

 national Weather Schedules Service "O" 7330.6. 



FACSIMILE DATA 



Most Naval Weather Service offices display 

 the current weather charts, plus those for the 

 past 24 hours or longer (depending on office 

 routine). This display is designed to afford 

 maximum usage to the forecaster, as well as 

 a ready reference for pilots and other author- 

 ized personnel. However, before this can be 

 accomplished, the observer must be able to 

 readily identify the various charts. 



All facsimile products will have a data block 

 affixed to them; figure 11-40 is an example 

 of the data block. This data block identifies 

 the chart as to the type, geographical loca- 

 tion, originator, date, and time. Although these 

 data usually are found in the lower left-hand 

 corner of the chart, they may appear anywhere. 



NATIONAL WEATHER 



SERVICE 



2IOOZ 



TUE 



JUL 



24 



1973 



NI20. 



NMC 



SFC 



ANALYSIS 



ASUS 









NI20. 



209.418 

 Figure 11-40. — Example of a facsimile chart data 

 block. 



Using the same publication referred to in the 

 previous section on teletype data, the type and 

 geographical location can be determined. 



Figures 11-41, 11-42, and 11-43, show some 

 examples of facsimile charts; however, there 

 are many other charts showing other data and 

 other areas. These can easily be identified 

 if you can read the data block. In fact, after 

 working with these charts a short time you 

 will be able to identify them simply by noting 

 the type of data that is on them. 



A vast number of weather charts are avail- 

 able through the National Meteorological Fac- 

 simile (NAMFAX) Circuits for stations in the 

 United States, and through the Fleet Facsimile 

 Broadcast for ships and overseas stations. A 

 few of the varied weather charts prepared for 

 facsimile transmission are as follows: 



1. Prognostic (prog) charts are simply the 

 basic charts projected into the future. Among 

 the many prog charts, the most commonly used 

 and the most important ones are the surface 

 prog charts, the constant pressure prog charts, 

 sea condition prog charts, severe weather out- 

 look charts, significant weather (high-level prog- 

 noses, and the 5-day prog charts.) 



2. Weather depiction charts are regularly 

 transmitted over the facsimile network. They 

 are charts which outline areas of significant 

 weather. The entries on this chart include sky 

 cover, ceiling or height of lowest scattered 

 clouds at stations reporting only scattered clouds, 

 visibility 6 miles or less, and any weather 

 the stations are experiencing. Areas with ceilings 

 below 1,000 feet or visibilities below 3 miles, 

 or both, are outlined, and areas with ceilings 

 1,000 to 5,000 feet inclusive and visibilities 

 3 miles or greater are scalloped outlined. For 



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