Area Forecast Background:
- Area forecasts are regional forecasts
Issuance & Validity:
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Issuance:
- Issued 3 times daily (times vary by area)
- Issued for: [Figure 1]
- Boston (BOS)
- Chicago (CHI)
- Salt Lake City (SLC)
- San Francisco (SFO)
- Dallas/Fort Worth (DFW)
- Miami (MIA)
- Gulf of Mexico (GULF)
- Hawaii
- Alaska
- Caribbean Areas
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Validity:
- Valid for 12 hours forecast and 6 hours outlook (18 total)
- Data is forecasted
Categorial Outlooks:
- Categorical outlook terms, describing general ceiling and visibility conditions for advanced planning purposes are used only in area forecasts
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LIFR (Low IFR):
- Ceiling less than 500 feet and/or visibility less than 1 mile
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IFR:
- Ceiling 500 to less than 1,000 feet and/or visibility 1 to less than 3 miles
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MVFR (Marginal VFR):
- Ceiling 1,000 to 3,000 feet and/or visibility 3 to 5 miles inclusive
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VFR:
- Ceiling greater than 3,000 feet and visibility greater than 5 miles; includes sky clear
- The cause of LIFR, IFR, or MVFR is indicated by either ceiling or visibility restrictions or both
- The contraction "CIG" and/or weather and obstruction to vision symbols are used
- If winds or gusts of 25 knots or greater are forecast for the outlook period, the word "WIND" is also included for all categories including VFR
- Examples:
- LIFR CIG: low IFR due to low ceiling
- IFR FG: IFR due to visibility restricted by fog
- MVFR CIG HZ FU: marginal VFR due to both ceiling and visibility restricted by haze and smoke
- IFR CIG RA WIND: IFR due to both low ceiling and visibility restricted by rain; wind expected to be 25 knots or greater
Area Forecast Reports:
- Area forecasts are reported using four elements:
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Communications and Product Header:
- 000 does not apply to the forecast
- FA indicates an Area Forecast with a World Meteorological Organization (WMO) header [Figure 2]
- FAUS41: Boston Area
- FAUS42: Miami Area
- FAUS43: Chicago Area
- FAUS44: Dallas, Ft. Worth Area
- FAUS45: Salt Lake City Area
- FAUS46: San Francisco Area
- The issuing agency will be listed:
- KKCI: Aviation Weather Center (AWC)/Meteorological Watch Office (MWO) in Kansas City
- PAWU: Alaska Aviation Weather Unit (AAWU)/MWO in Anchorage
- PHFO: Honolulu Weather Forecast Office (WFO)/MWO in Honolulu
- An Advanced Weather Interactive Processing System (AWIPS) ID will be included which corresponds with the WMO header
- The ID is now replaced with the WMO header but is left there to be clear for those who are used to an older system
- FA1: Corresponds with FAUS41
- FA2: Corresponds with FAUS42
- FA3: Corresponds with FAUS43
- FA4: Corresponds with FAUS44
- FA5: Corresponds with FAUS45
- FA6: Corresponds with FAUS46
- The ID is now replaced with the WMO header but is left there to be clear for those who are used to an older system
- The area the forecast applies to is listed again (clearly) but with a "C" appended, which indicates clouds and weather forecast
- BOSC: Boston (clouds and weather forecast)
- MIAC: Miami (clouds and weather forecast)
- CHIC: Chicago (clouds and weather forecast)
- DFWC: Dallas, Ft. Worth (clouds and weather forecast)
- SLCC: Salt Lake City (clouds and weather forecast)
- SFOC: San Francisco (clouds and weather forecast)
- Issued date: day of the month and time; valid time begins 15 minutes later
- 101745: Issued on the 10th day of the month at 1745 Zulu (Z)
- Valid time begins on the hour at 1800Z
- 101745: Issued on the 10th day of the month at 1745 Zulu (Z)
- "SYNOPSIS AND VFR CLDS/WX" is a standard line for all forecasts
- Validity times are listed last for the synopsis, clouds and weather, and outlook:
- SYNOPSIS VALID UNTIL 111200: valid until the 11th day of the month at 1200Z
- CLOUDS/WX VALID UNTIL 110600: valid until the 11th day of the month at 0600Z
- OTLK VALID 110600-111200: valid between the 11th day of the month from 0600Z to 1200Z
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Precautionary Statements:
- Part of all area forecasts [Figure 3]
- See AIRMET Sierra and IFR conditions and mountain obscuration
- Thunderstorms imply possible severe or greater turbulence, severe icing, low-level wind shear, and instrument conditions
- Heights which are not Mean Sea Level (MSL) are noted by the letters AGL (above ground level) or CIG (ceiling)
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Synopsis:
- Contains many abbreviations that are found on various weather reports [Figure 4]
- Brief description of the location and movement of fronts, pressure systems, and circulation patterns
- Valid for 18 hours or until the date time group (DTG) in the same format as the issue DTG
- SYNOPSIS VALID UNTIL 251400: Synopsis valid until the 25th day at 1400Z
- Contains many abbreviations that are found on various weather reports [Figure 4]
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VFR Clouds and Weather: