Chapter 17 — ADMINISTRATION, PUBLICATIONS, AND SUPPLY 



ROUTE FORECASTS. — Route forecasts refer 

 to weather conditions for a given period along 

 a route but not necessarily to a particular 

 flight. Route forecasts are primarily for local 

 use at a particular station or in a particular 

 area and are prepared as directed by local 

 authority. They may be combined with area 

 or local forecasts for use in planning flight 

 operations. 



The information in a route forecast is es- 

 sentially the same as in an area forecast, but 

 is applied to the particular route for which the 

 forecast is prepared. 



Route forecasts exchanged on civil or inter- 

 national circuits in accordance with ICAO Re- 

 gional Procedures are in the code specified for 

 use in the region for which issued. 



FLIGHT FORECASTS. — Flight forecasts re- 

 fer to the weather conditions on successive 

 stages of particular flights. These forecasts 

 are similar to route forecasts except that they 

 are prepared for separate and particular flights. 



Flight forecasts may be prepared by the 

 weather unit of one station for use by another 

 station not having a sufficient number of quali- 

 fied personnel to prepare these forecasts. 



Flight forecasts may be verbal or written, 

 depending on whether the specified flight re- 

 quires a flight plan or not. For written flight 

 forecasts, DD Form 175-1 is used and provides 

 a comprehensive record of weather flight plan- 

 ning information for pilots and flight clearance 

 authority. This flight weather briefing form 

 includes entries for takeoff, en route, and ter- 

 minal weather data. For instructions for com- 

 pleting this form refer to NAVWEASERVCOM 

 Instruction 3145.1( ). 



NAVWEASERVCOMINST 3 140. 53 ( ) provides 

 instructions for preparation of a U.S. Navy 

 Flight Weather Packet, which is issued when 

 requested. The packet contains a Flight Forecast 

 Folder CNWS Form 3140/25 (Appendix XIII) 

 Flight Weather Briefing DD Form 175-1, HWD 

 (horizontal weather depiction) -high or low level — 

 and an upper wind chart; other data will be 

 included upon request. 



TERMINAL FORECASTS. — Terminal fore- 

 casts refer to weather conditions at air sta- 

 tions, or airports, for a given period, which 



may affect the landing or takeoff of aircraft. 

 These forecasts are prepared and coded in 

 accordance with NAVWEASERVCOMINST 

 3143.1( ). 



FLIGHT BRIEFING AND CLEARANCE.— 

 Flight briefing is the oral discussion with flight 

 crews of the general and specific weather con- 

 ditions which exist, or are expected, along the 

 route of a flight and at the terminal. These 

 briefings present all pertinent weather infor- 

 mation necessary in the planning of flights 

 or which may otherwise be of interest. Flight 

 briefings should make available to flight crews 

 pertinent information from current reports and 

 weather maps, and from area, route, flight, 

 and terminal forecasts. Weather units conducting 

 flight briefings maintain complete displays of 

 weather maps, weather reports, and forecasts 

 for the perusal of flight personnel and for use 

 in conducting flight briefings. 



IN-FLIGHT WEATHER SERVICE. — Weather 

 units provide such weather information as may 

 be requested by aircraft in flight. In addition, 

 these units are familiar with those in-flight 

 weather services maintained by the Federal 

 Aviation Administration and other government 

 agencies in their area. 



Selected Flight Service Stations (FSSs) hav- 

 ing voice facilities on continuously operated 

 radio ranges or radio beacons broadcast weather 

 reports and other airways information at 15 

 minutes past each hour. In addition, all FSSs 

 also provide direct pilot-to-weather briefer serv- 

 ice. Details concerning these services may be 

 found in the Airman's Information Manual. 



Pilot-to-forecaster service (PFSV) employed 

 extensively by the Air Weather Service of the 

 Air Force is in use by selected Naval Weather 

 Service units. Refer to the current edition of 

 En Route-Supplement for the naval air stations 

 where this service is available. 



Ships operating within radio range of an air- 

 ways communications station should, when ap- 

 propriate, use it as a source of hourly weather 

 reports by reception of scheduled broadcasts. 



OTHER METEOROLOGICAL 

 SERVICES 



Climatological Services 



The NAVWEASERV provides climatological 

 services to the Navy through its NWSEDs, 



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