JO 7110.10X
Effective Date:
April 3, 2014
Subject:  Flight Services

Section 6. En Route Flight Advisory Service (EFAS)

4-6-1. GENERAL

The purpose of EFAS, radio call “FLIGHT WATCH” (FW), is to provide en route aircraft with timely and pertinent weather data tailored to a specific altitude and route using the most current available sources of aviation meteorological information.

EFAS/Flight Watch outlets are listed in the Airport/Facility Directory (AFD).


Prior to assuming the duties of the flight watch position:

a. Perform a thorough self­briefing by reviewing all pertinent weather data.

b. When relieving a specialist on the flight watch position, obtain a pre­duty briefing from the person being relieved.

c. When appropriate, obtain a briefing of current and forecast weather within the flight watch area (FWA) from the CWSU of the associated air route traffic control center (ARTCC). (See para 4­6­5.)

d. Maintain currency of weather conditions and trends while assigned the flight watch position by reviewing new or revised meteorological issuances and by observing weather trends contained in current weather reports and PIREPs.


a. Tailor en route flight advisories to the phase of flight that begins after climb out and ends with descent to land. Current weather and terminal forecast at the airport of first intended landing and/or the alternate airport must be provided on request. When conditions dictate, provide information on weather for alternate routes and/or altitudes to assist the pilot in the avoidance of hazardous flight conditions. Advise the pilot to contact the adjacent FWA when adverse weather conditions along the intended route extend beyond the FWA.

b. EFAS must not be used for routine inflight services; for example, flight plan filing, position reporting, or full route (preflight) briefings. If a request for information is received that is not within the scope of flight watch, advise the pilot of the appropriate FSS to contact.

“Cessna Four Seven Five Eight Xray, Cleveland Flight Watch, contact Altoona Radio on one two two point four to file your flight plan.”

c. Suggest route or destination changes to avoid areas of weather which in the judgment of the specialist constitute a threat to safe flight.

d. Alert the associated CWSU or WFO immediately of reported or observed significant weather that is not included in aviation forecasts.


a. Use frequency 122.0 MHz to provide flight watch services to aircraft below FL 180.

b. Use the assigned discrete frequency to provide flight watch services to aircraft at FL 180 and above. This frequency can also be used for communications with aircraft below FL 180 when communication coverage permits.

c. Aircraft operating at FL 180 or above that contact flight watch on frequency 122.0 MHz should be advised to change to the high altitude discrete frequency for Flight Watch.

(Aircraft identification) (facility) FLIGHT WATCH, FOR SERVICE AT YOUR ALTITUDE. CONTACT FLIGHT WATCH ON (frequency).

d. Avoid the simultaneous keying of two or more transmitters on the same frequency. This action can block or hinder communications.

Frequency 122.0 MHz RCF outlets are geographically located to ensure communications coverage at 5,000 feet AGL and above over the conterminous United States. High altitude discrete frequency RCF outlets are geographically located to ensure communications coverage between FL 180 and FL 450 over the EFAS facility's area of responsibility. Communications practices should be guided by these restrictions.


The NWS support function for EFAS is as follows:

a. The associated CWSU is designated as the primary support facility for each flight watch area. The CWSU should be contacted at least once per shift for a general briefing of meteorological conditions which are impacting, or expected to impact, aviation weather within the flight watch /ARTCC area.

Due to assigned priorities, the CWSU meteorologist may not be able to provide in­depth briefing service for up to 2 hours after the start of the first shift of the CWSU unit. (See FAA Order JO 7210.3, Para 14­3­6, National Weather Service (NWS) Support, for establishment of operational support.)

b. During the period when the CWSU is not available to provide consultation service, WFOs are responsible for responding to EFAS facility requests regarding weather conditions prevailing within the WFO area of responsibility. The EFAS specialist should contact the responsible WFO directly for clarification of forecasts or questions concerning products originated by the WFO.

The ARTCC/EFAS area may encompass multiple WFO areas.

c. Consult with the Aviation Weather Center (AWC), as appropriate, when further information or clarification is needed regarding WS, WST, WA, and FA products.


a. Actively solicit and disseminate PIREPs in accordance with Chapter 9, Section 2. Additionally, PIREPs concerning winds and temperature aloft, wind shear, turbulence, and icing must be solicited and disseminated when one or more of these conditions or criteria exist. Flight watch specialists must solicit sufficient PIREPs to remain aware of flight conditions.

b. Maintain a graphic display of pertinent PIREPs within the flight watch area. Periodically review the display, and actively solicit additional PIREPs when necessary to ensure completeness and accuracy of the information.

c. Requests for special solicitation of PIREPs from other facilities or the NWS must be honored as rapidly as operations permit.


a. Prior to assuming flight watch duties, the specialist must review, as a minimum, the graphic information listed below (if available). After assuming duties, the specialist must continue to review graphic and written data as needed during the watch to update and maintain a thorough knowledge of weather synoptic and forecast information affecting aviation operations.

1. Weather Depiction.

2. Surface Analysis.

3. Forecast Winds Aloft.

4. G­AIRMET Graphic.

5. 12­ and 24­ hour low-level significant weather prognosis.

6. 36­and 48­ hour low-level significant weather prognosis.

7. High-level significant weather prognosis.

8. Freezing level graphic.

9. Freezing level analysis.

10. *Current Icing Product (CIP).

11. *Forecast Icing Product (FIP).

12. *Graphical Turbulence Guidance (GTG).

13. 850 MB upper air analysis.

14. 700 MB upper air analysis.

15. 500 MB upper air analysis.

16. 300 MB upper air analysis.

17. 250 MB upper air analysis.

18. 200 MB upper air analysis.

19. 500 MB heights and vorticity analysis.

20. 500 MB heights and vorticity prognosis.

21. Severe weather outlook.

22. Lifted index analysis.

23. National weather radar summary.

24. Maximum temperature 24­ and 36­ hour forecast.

25. Minimum temperature 24­ and 36­ hour forecast.

*Denotes weather products that are supplementary. They may only be used to enhance situational awareness. When discrepancies are noted, the specialist must base their decision on the primary weather product.

b. Access local and remote weather displays as necessary to maintain current knowledge of precipitation intensity, movement, and coverage. Provide pertinent real­time weather radar information that will directly impact the aircraft's flight.


Notification of temporary outages, either equipment or operational, must be made in accordance with FAA Order JO 7930.2, Notices to Airmen (NOTAM). In order to provide continuous service, notify the specialist responsible for the adjacent flight watch area of outages.


a. Emergency situations must be handled in accordance with Chapter 5.

b. When working an aircraft in an emergency situation over a remote outlet, the normal procedure is to provide assistance on the initial contact frequency. Flight watch specialists should bear in mind that air traffic facilities based at, or near to, the remote location may be in a better position to assist the pilot. A decision to affect a frequency change should be based on the situation and circumstances involved in the emergency.


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