Area Forecasts

Decode and apply information contained in the Aeronautical Information Publication (AIP Book) and the Enroute Supplement Australia (ERSA) to understand Aerodrome Weather Forecasts and Reports.

AIP
Meteological Services: Gen 3.5
Definitions and Abbreviations: Gen 2.2

ERSA
Meteological Services

The AIP and ERSA Books can be purchased or access online and/or downloaded from the Airservices Australia web site after agreeing to their Terms and Conditions. Airservices Australia

ARFOR Breakdown

This is a breakdown of an ARFOR with added decoding explanations for the code with aeronautical operational meteorological information.

AREA22
ARFOR AMEND AREA FORECAST 300415 TO 301700 AREA 22
(The date/time groups in the preceding line are in the form ddhhmm UTC, thus the last group reads (April) 30, 1700 UTC which is (May) 01, 0300 hrs (3.00 am) EST)

AMEND OVERVIEW
FINE APART FROM ISOLATED SHOWERS IN FAR NORTHEAST TILL 11Z
(The time group in the preceding line is in the form hh UTC [Z indicates UTC], thus the isolated showers may persist until (April 30) 11(00) UTC or (April 30) 2100 hrs (9.00 pm) EST)

WIND

2000	5000	7000	10000	14000	18500
07010	VRB10	VRB15	24015 ZERO	22015 MS06	21020 MS15

(The preceding lines show the wind direction and speed at six levels. The terms zero, MS06 and MS15 refer to the temperature °C at the higher altitudes, MS = minus)

CLOUD
SCT CU/SC 4500/9000, LOCALLY BKN IN NE TILL 11Z
(Scattered [3 to 4 oktas] cumulus and stratocumulus cloud with bases at 4500 FT and tops at 9000 FT, locally broken [5 to 7 oktas] in northeast till 1100 UTC)

AMEND WEATHER
SH IN NE
(Showers in northeast)

VISIBILITY
6KM SH
(Visibility better than 10KM, only reducing to 6KM in showers)

FREEZING LEVEL
10000 IN SE / 12000 IN NW
(Freezing level [0 C] is at 10,000 FT in the southeast and 12,000 FT in the northwest)

ICING
NIL
(Icing is none)

TURBULENCE
MOD IN CU
(Turbulence is moderate in cumulus cloud)

AREA QNH 03/07
(The area 22 pressure is valid from 0300 to 0700 UTC)

AREA 22: NW OF YMIA/YMOR 1025, REST 1027
(The area 22 pressure is 1027 hPa; while northwest of a line commencing at YMIA [Mildura] to YMOR [Moree] is 1025 hPa)

ARFOR Example

AREA21 (21)
AMD AREA QNH 11/13
AREA 21: 1015

AMEND AREA FORECAST 101000 TO 102300 AREA 21

OVERVIEW
AREAS OF BROKEN LOW CLOUD WITH DRIZZLE ON AND E OF RANGES

WIND

2000	5000	7000	10000	14000	18500
18020	20015	20015	23020 PS02	24030 MS05	24045 MS14

REMARK: WINDS BELOW 5000FT 140/20 KT TILL 15Z

CLOUD
BKN ST 1000/2000 SEA/COAST CONTRACTING N.
BKN ST/SC E YBTH/YCRG 2000/4500 SEA/COAST/E SLOPES, 3000/5000 RANGES.
FEW CU/SC 6000/8000 REMAINDER.

WEATHER
DZ

VISIBILITY
4000M IN DZ

FREEZING LEVEL
11000

ICING
NIL

TURBULENCE
NIL SIG

AMD CRITICAL LOCATIONS: [CLOUD HEIGHTS ABOVE MEAN SEA LEVEL]
AMD MT VICTORIA: BKN ST 3700 [CLOUD ON GROUND]
AMD BOWRAL: 9999 BKN ST 3000 FM14 BKN ST 2200 [CLOUD ON GROUND]