Chapter 2. Broadcast Procedures

Section 1. General

2-1-1. TYPES OF BROADCASTS

Weather and flight information shall be broadcast/ recorded by one or more of the following categories:

a. Transcribed Weather Broadcast (TWEB). (Alaska only.)

b. Telephone Information Briefing Service (TIBS).

c. Hazardous Inflight Weather Advisory Service (HIWAS).

d. Meteorological Information for Aircraft in Flight (VOLMET ICAO).

2-1-2. SPEECH RATE

Data shall be spoken at a rate of 100 to 120 words-per-minute.

2-1-3. INTERRUPTION OF BROADCAST

Interrupt broadcast only when you believe that a pilot requires immediate attention; e.g., to issue an airport advisory. When a pilot calls during a broadcast:

a. Broadcast for a short interval on the frequency to which the pilot is listening simultaneously with the broadcast frequencies, and complete the aircraft contact immediately after the broadcast.

b. If the pilot repeats the call, interrupt the broadcast and answer the call.

2-1-4. REDUCING RECORDED WEATHER INFORMATION SERVICES

Recorded weather information services (TWEB and TIBS) may be reduced during the hours of 1800-0600 local time only. Resumption of full broadcast service should be adjusted seasonally to coincide with daylight hours. During the period of reduced broadcast, record a statement indicating when the broadcast will be resumed and to contact Flight Service for weather briefing and other services.

PHRASEOLOGY-
THE TIBS RECORDING IS SUSPENDED. REGULAR RECORDED WEATHER SERVICE WILL BE RESUMED AT (time) ZULU/ (time) LOCAL. FOR PILOT WEATHER BRIEFING AND OTHER SERVICES CONTACT A FLIGHT SERVICE FACILITY (phone number or additional telephone instructions, as appropriate).

PHRASEOLOGY-
THE TWEB RECORDING IS SUSPENDED. REGULAR RECORDED WEATHER SERVICE WILL BE RESUMED AT (time) ZULU/ (time) LOCAL. FOR PILOT WEATHER BRIEFING AND OTHER SERVICES CONTACT A FLIGHT SERVICE FACILITY (frequency or phone number, as appropriate).

2-1-5. ANNOUNCING MISSING ITEMS

With the exception of RVR, announce the word "MISSING" when any items or components of a weather report are not reported, or in place of unreadable or obviously incorrect items or portions of weather reports. If the complete report is not available for broadcast, state the location and the word "MISSING." When appropriate, instead of speaking the name of several locations with missing reports, announce: "OTHER SCHEDULED REPORTS MISSING."

NOTE-
On occasion, a parameter from an automated observation may be reported as missing in the body of the report but is available as a manually reported parameter in the remarks section. When the report is spoken, include the manually reported element in its proper sequence within the report.

2-1-6. WEATHER REPORT PHRASEOLOGY

Use the following phraseology and procedures for radio-telephone communications and broadcast of surface weather observations:

a. Location.

1. Announce the geographic name (not the identifier) once for broadcasts.

2. When the location name is duplicated within 500 miles, follow the location name with the state name.

EXAMPLE-
"Wilmington, North Carolina."
"Wilmington, Delaware."

3. When weather reports originate at more than one airport at the same geographical location, identify the airport.

EXAMPLE-
"Chicago Midway."
"Chicago O'Hare."

4. Where it is considered necessary and is requested by the military base commander, broadcast military observations by stating the location, the name of the airport if different, and the controlling military branch.

EXAMPLE-
"Fort Riley, Marshall Army Air Field."
"Andrews Air Force Base."
"Norfolk Naval Air Station."

b. Automated Observation. If AUTO appears after the date/time element, follow the location announcement with the phrase "AUTOMATED."

PHRASEOLOGY-
(Location) AUTOMATED.

c. Special Reports. If a special report is available at the time of the broadcast, follow the location with the words "SPECIAL REPORT, (last two digits of the time) OBSERVATION."

d. Wind Direction and Speed. Announce wind direction and speed by stating the word WIND followed by the separate digits of the wind direction to the nearest 10 degrees and the separate digits of the speed. A "G" between two wind speed values is announced as GUSTS. Broadcast local wind as it appears in the report. Announce the variability of wind at the end of the wind group. (See TBL 2-1-1.)

TBL 2-1-1
Wind Direction and Speed

e. Visibility. Announce visibility as follows:
(See TBL 2-1-2.)

TBL 2-1-2
Visibility

NOTE-
When visibility is less than 3 miles and variable, the variable limits will be reported in the remarks.

f. RVR. When RVR is reported, announce in accordance with TBL 2-1-3. Omit RVR when it is not reported. Do not announce as missing.

TBL 2-1-3
RVR

g. Weather Elements. TBL 2-1-4 depicts sample phraseology for weather element contractions. Intensity refers to precipitation, not descriptors. Proximity is spoken after the phenomenon to which it refers. Descriptors are spoken ahead of weather phenomenon with the exception of "showers" which is spoken after the precipitation. Table TBL 2-1-8 contains a complete list of weather elements and appropriate phraseology.

TBL 2-1-4
Examples of combining intensity, descriptors and weather phenomenon.

h. Ceiling and sky coverage.

1. Broadcast Sky Coverage in the same order as reported on the weather observation. Announce ceiling as follows: (See TBL 2-1-5.)

TBL 2-1-5
Ceiling and Sky coverage

2. State cloud heights in tens, hundreds and/or thousands of feet. (See TBL 2-1-6.)

TBL 2-1-6
Cloud Heights

NOTE-
When the ceiling is less than 3,000 feet and variable, the variable limits will be reported in the remarks.

3. Announce sky conditions as indicated.
(See TBL 2-1-7.)

TBL 2-1-7
Sky Conditions

TBL 2-1-8
Weather Elements

4. The following are examples of broadcast phraseology of sky and ceiling conditions:
(See TBL 2-1-9.)

TBL 2-1-9
Sky and ceiling conditions

i. Temperature and Dew Point. Announce temperature and dew point in degrees Celsius. Temperatures below zero are preceded with an M and are announced by prefixing the word MINUS to the values. When the temperature and dew point spread is greater than 3 degrees, broadcast only the temperature. (See TBL 2-1-10.)

TBL 2-1-10
Temperature and Dew Point

j. Altimeter Setting. Announce the four digits of the altimeter setting. (See TBL 2-1-11.)

TBL 2-1-11
Altimeter Setting

k. Remarks. Announce pertinent remarks. Do not broadcast additive data or other information intended for NWS analysis or processing that does not contribute to the description of the weather occurring at the station. (See TBL 2-1-12.)

TBL 2-1-12
Remarks

2-1-7. CURRENT DATA

An aviation surface report is considered current for 1 hour beyond the standard time of observation (H+00) unless superseded by a special or local observation or by the next hourly report. Do not broadcast obsolete data.