Tutorial
FA
An Area Forecast (FA) reports the general weather conditions of a particular region. The contiguous states are
divided into 6 regions for which area forecasts are prepared. This is a good source of weather information for
en route weather and helps to determine the weather conditions for airports that do not provide terminal forecasts.
The FA gives a 12-hour forecast plus a 6-hour outlook with information describing 5 specific weather conditions:
An Area Forecast (FA) report example is shown below.
SLCH FA 191140 HAZARDS VALID UNTIL 200000 ID MT WY NV UT CO AZ NM FLT PRCTNS . . . ICG . . . WY CO . . . TURBC . . . ID WY . . . IFR . . . WY CO . . . MTN OBSCN . . . WY CO TSTMS IMPLY PSBL SVR OR GTR TURBC SVR ICG AND LLWS NON MSL HGTS NOTED BY AGL OR CIG. THIS FA ISSUANCE INCORPORATES THE FOLLOWING AIRMETS STILL IN EFFECT . . . NONE. . . . SLCS FA 191140 SYNOPSIS VALID UNTIL 200600 . CDFNT SERN WY NRN CO CNTRL UT MOVG SEWD 30 KTS. . . . . SLCI FA 191140 ICING AND FRZLVL VALID UNTIL 200000 WY CO . FROM CPR TO ICT TO OKC TO PUB TO CPR MDT MXD ICGICIP ABV FRZLVL TO ARND 150. CONDS XPCD TO CONT BYD 0000. . FRZLVL . . . SFC NWRN PTNS AREA SLPG TO 120 GLD TO GAG LINE. . . . . SLCT FA 191140 TURBC VALID UNTIL 200000 ID WY FROM BOI TO LAR TO SLC TO BOI OCNL MDT TURBC 250-380 DUE TO JTSTR . . . . SLCC FA 191140 SGFNT CLOUD AND WX VALID UNTIL 200000 . . OTLK 200000-200-600 . IFR . . . WY CO FROM DEN TO GLD TO GCK TO PUB TO DEN OCNL CIGS BLO 10 AND VSBYS BLO 3R-S-. . CO E OF DVD . . . 15-25 OVC WITH OCNL CIGS BLO 10 OVC VSBYS BLO 3R-S-. OTLK . . . MVFR CIG BCMG VFR BY 02Z.
AREA FORECAST REPORT DECODED BELOW BY SECTION:
Section 1
SLCH FA 191140 HAZARDS VALID UNTIL 200000 ID MT WY NV UT CO AZ NM FLT PRCTNS . . . ICG . . . WY CO . . . TURBC . . . ID WY . . . IFR . . . WY CO . . . MTN OBSCN . . . WY CO TSTMS IMPLY PSBL SVR OR GTR TURBC SVR ICG AND LLWS NON MSL HGTS NOTED BY AGL OR CIG. THIS FA ISSUANCE INCORPORATES THE FOLLOWING AIRMETS STILL IN EFFECT . . . NONE. . . .
Explanation for Section 1
Salt Lake City (SLC), Hazards section (H), Area Forecast (FA), 19th day of month at 1140 Zulu time
These hazards are valid from 1200 Z on the 19th day to 0000Z on the 20th day of the month
Hazards for the states listed: Idaho, Montana, Wyoming, Nevada, Utah, Colorado, Arizona, New Mexico
Flight Precautions . . . icing for Wyoming and Colorado; turbulence for Idaho and Wyoming; Instrument Flight Rules
(IFR);conditions for Wyoming and Colorado; mountain obscuration in Wyoming and Colorado
Thunderstorms imply possible severe or greater turbulence, severe icing and low-level windshear
Non-mean sea level (MSL) heights are noted by the letters AGL (above ground level) or CIG (ceiling). (All heights
are expressed in hundreds of feet.)
No AIRMETs were in effect at the time of this report.
Section 2
SLCS FA 191140 SYNOPSIS VALID UNTIL 200600 . CDFNT SERN WY NRN CO CNTRL UT MOVG SEWD 30 KTS.
Explanation of Section 2
This is the Salt Lake City synopsis (SLC S) section which summarizes the location and movement of pressure systems,
fronts and circulation patterns. It is valid for an 18 hour period from the 19th day of the month beginning at
1140 and ending on the 20th day at 0600 Zulu time.
A cold front is reported (CDFRNT) running from southeastern (SERN) Wyoming through northern Colorado to central
Utah (WY NRN COCNTRL UT) the wind will be moving to the southeast at 30 knots (MOVG SEWD 30 KTS).
Section 3
SLCI FA 191140 ICING AND FRZLVL VALID UNTIL 200000 WY CO . FROM CPR TO ICT TO OKC TO PUB TO CPR MDT MXD ICGICIP ABV FRZLVL TO ARND 150. CONDS XPCD TO CONT BYD 0000. . FRZLVL . . . SFC NWRN PTNS AREA SLPG TO 120 GLD TO GAG LINE.
Explanation of Section 3
This is the Salt Lake City icing and freezing level forecast (SLCI) section which is valid through 0000 Zulu on
the 20th of the month for Wyoming and Colorado.
In an area extending from Casper, Wyoming to Wichita, Oklahoma to Oklahoma City, Oklahoma to Pueblo, Colorado expect
moderate, mixed icing in clouds with precipitation above the freezing level to approximately 15,000 feet in altitude.
These conditions are expected to continue past the 0000 Zulu time.
The freezing level will remain at the surface in the northwestern portions of the area, sloping to 12,000 feet
along a line from Goodland to Gage.
Section 4
SLCT FA 191140 TURBC VALID UNTIL 200000 ID WY FROM BOI TO LAR TO SLC TO BOI OCNL MDT TURBC 250-380 DUE TO JTSTR
Explanation of Section 4
This is the Salt Lake City turbulence and low-level windshear forecast (SLCT) section which is valid through 0000
Zulu on the 20th of the month for Idaho and Wyoming.
In an area from Boise (BOI) to Laramie (LAR) to Salt Lake City (SLC)
There will exist moderate turbulence from 25,000 to 38,000 feet due to the jetstream.
Section 5
SLCC FA 191140
SGFNT CLOUD AND WX VALID UNTIL 200000 . . OTLK 200000-200-600 . IFR . . . WY CO FROM DEN TO GLD TO GCK TO PUB TO DEN OCNL CIGS BLO 10 AND VSBYS BLO 3R-S-. . CO E OF DVD . . . 15-25 OVC WITH OCNL CIGS BLO 10 OVC VSBYS BLO 3R-S-. OTLK . . . MVFR CIG BCMG VFR BY 02Z.
Explanation of Section 5
This is the Salt Lake City significant cloud and weather forecast (SLCC) section which is valid through 0000 Zulu
on the 20th of the month.
The outlook is valid from 0000 to 0600 Zulu on the 20th of the month.
Instrument Flight Rules (IFR) conditions for Wyoming and Colorado.
In an area bounded by Denver to Goodland to Garden City to Pueblo, expect occasional ceilings below 1,000 feet
with visibilities below (less than) 3 miles in light rain and light snow.
In Colorado, east of the continental divide (DVD), overcast (OVC) conditions between 1,500 - 2,500 feet with occasional
ceilings (OCNL CIGS) below 1,000 feet and visibilities (less than) below 3 miles in light rain and light snow.
The outlook calls for marginal visual flight rules (MVFR) with ceilings becoming (BCMG) visual flight rules 9VFR)
by 0200 Zulu time.
The Winds and Temperatures Aloft Forecast (FD) gives an estimate of wind direction as it relates to true north,
the wind speed (in knots) and the temperature (degrees Celsius) for selected levels of altitude.
FD KSJC 161640 DATA BASED ON 161200Z VALID 16180Z FOR USE 1700 -2100Z TEMPS NEG ABV 24000 FT 3000 6000 9000 12000 18000 24000 HOU 2619 2728+01 2635-05 2641-09 2654-21 2665-32 JOT 2526 2736+01 2642-06 2649-11 2662-22 2674-33
Line1
Winds and Temperature Aloft (FD), San Jose International Airport, CA, 16th day of month, time: 1640.
Line2
States that the forecast is based on observations made on the 16th day of the month at 1200 Zulu time.
Line3
Report is valid on the 16th day of the month at 1800 Zulu time and is to be used from 1700 - 2100 Zulu time. Temperatures
above 24,000 feet are always negative, this note indicates that the negative sign (-) is not shown on numbers for
30,000 feet and above.
Line 4
This line contains the column headings for the information now shown in chart form. Each column indicates the altitude
at which the winds and temperatures were measured. These are recorded in feet (FT) beginning with 3,000 and as
this is a partial chart only going up to 24,000 feet.
Line5
Location identification code (HOU) for Houston, Texas. The next group of 6 numbers is broken up by pairs. The first
2 digits (26) give the true direction from which the wind is blowing which is 260 degrees. The second pair of digits
(19) gives the wind speed in knots (19 knots). The third pair of numbers indicate the temperature, however temperatures
are not reported for 3,000 feet and less. So, going to the second group of numbers (2728-01) the information tells
us that at 6,000 feet the winds are from 270 degrees with a windspeed of 28 knots and a temperature of 1 degree
C.
Line 6
This line contains information for Joliet, IL (JOT) and is read the same as above.
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