Area forecast
Encyclopedia
An Aviation Area Forecast (FA or ARFOR) is a message product of the National Weather Service
(NWS) in the United States
. There are also weather charts forecast like SIGWX
. FA encompasses the weather
conditions over a large regional area and is considered one of the better sources of information for en-route weather. It is also beneficial in verifying airport conditions at airports that do not have terminal aerodrome forecasts
. FA's are issued three times daily in all 48 neighboring states of the United States
, and modified as required. The NWS offices also issue FA's for Alaska
and Hawaii
, but Alaska uses a slightly different format.
Area forecasts (FA's):
Some abbrevaitions that are used in FA's include:
Status of an FA can be:
National Weather Service
The National Weather Service , once known as the Weather Bureau, is one of the six scientific agencies that make up the National Oceanic and Atmospheric Administration of the United States government...
(NWS) in the United States
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
. There are also weather charts forecast like SIGWX
SIGWX
SIGWX is a Significant Weather Chart defined by ICAO.Weather charts being issued by World Area Forecast Centres , presenting the most important meteorological phenomena relevant especially for air traffic transport...
. FA encompasses the weather
Weather
Weather is the state of the atmosphere, to the degree that it is hot or cold, wet or dry, calm or stormy, clear or cloudy. Most weather phenomena occur in the troposphere, just below the stratosphere. Weather refers, generally, to day-to-day temperature and precipitation activity, whereas climate...
conditions over a large regional area and is considered one of the better sources of information for en-route weather. It is also beneficial in verifying airport conditions at airports that do not have terminal aerodrome forecasts
Terminal Aerodrome Forecast
In meteorology and aviation, TAF is a format for reporting weather forecast information, particularly as it relates to aviation. "TAF" is an acronym of Terminal Aerodrome Forecast or, in some countries, Terminal Area Forecast....
. FA's are issued three times daily in all 48 neighboring states of the United States
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
, and modified as required. The NWS offices also issue FA's for Alaska
Alaska
Alaska is the largest state in the United States by area. It is situated in the northwest extremity of the North American continent, with Canada to the east, the Arctic Ocean to the north, and the Pacific Ocean to the west and south, with Russia further west across the Bering Strait...
and Hawaii
Hawaii
Hawaii is the newest of the 50 U.S. states , and is the only U.S. state made up entirely of islands. It is the northernmost island group in Polynesia, occupying most of an archipelago in the central Pacific Ocean, southwest of the continental United States, southeast of Japan, and northeast of...
, but Alaska uses a slightly different format.
Area forecasts (FA's):
- Issued 3 times daily
- Valid for 18 hours (12 hour forecast, plus 6 hour categorical outlook)
- Cover an area the size of several states
- Visibility is always stated in statute miles (SM)
- Comprise four sections
- a. A communications and header section
- i. Issue time of forecast
- ii. Valid times of the synopsis and the VFRVfRVfR is a German-language acronym that may appear in various contexts:*Verein für Raumschiffahrt, en:Society for Space Travel, a historical amateur rocket club in Germany...
CLOUDS/WX sections - iii. Area of coverage
- b. A precautionary statement section
- i. Warns users to check the AIRMETAIRMETAn AIRMET, or Airmen's Meteorological Information, is a concise description of weather phenomena that are occurring or may occur along an air route that may affect aircraft safety...
section for IFR and/or mountain obscuration - ii. Describes the hazards associated with all thunderstorm
- iii. Reminds users that all altitudes are given in MSLMSL- Organizations :* Major Series Lacrosse* Major Soccer League* Malaysia Super League* MBCgame Starleague * Metal Storm Limited, an Australian modern armament company...
, unless noted as AGLAGLAGL may refer to:* A Graphics Language, a high level language to control early HP plotters* Abergele and Pensarn railway station, United Kingdom, from its National Rail code* Above ground level, in aviation* Adobe Glyph List...
or CIG (ceilingCeiling (aeronautics)With respect to aircraft, a ceiling is the maximum density altitude an aircraft can reach under a set of conditions.The word ceiling can also refer to the height of the lowest obscuring cloud layer above the ground.-Service ceiling:...
)
- i. Warns users to check the AIRMET
- c. A synopsis section
- i. Brief summary of the location and movement of fronts, pressure systems and circulation patterns for an 18 hour period
- ii. References to low ceilings, reduced visibility and/or strong winds may be included
- d. A VFR CLOUDS/WX section
- i. Contains a 12 hour specific forecast, followed by a 6 hour categorical outlook
- ii. Broken down into geographical areas, and/or states
- iii. Describes cloud and weather affecting VFR flight operations, including precipitation, thunderstorms, and sustained surface winds 20 Kts or greater. Also includes visibility when the forecast to visibility is between 3 and 6 SM and/or obstructions to visibility
- a. A communications and header section
Some abbrevaitions that are used in FA's include:
- OCNL Occasional >50% chance for <1/2 of the forecast period
- ISOLD Isolated Single cells
- WDLY SCT Widely scattered <25% of the area affected
- SCT Scattered Areas of 25% to 54% of the area affected
- NMRS Numerous >55% of the area affected
- WDSPRD Widespread >55% of the area affected
Status of an FA can be:
- AMD Amended Includes AIRMETAIRMETAn AIRMET, or Airmen's Meteorological Information, is a concise description of weather phenomena that are occurring or may occur along an air route that may affect aircraft safety...
s, SIGMETSIGMETSIGMET, or Significant Meteorological Information, is a weather advisory that contains meteorological information concerning the safety of all aircraft. There are two types of SIGMETs, convective and non-convective...
s, and Convective SIGMETs - COR Corrected
- RTD Delayed