Aerodrome Forecasts

There are two types of aerodrome forecast, a TAF and a TREND.

TAF

A TAF is an aerodrome forecast provided for a specific aerodrome and presented in code. Cloud base is forecast in feet above aerodrome level and wind direction is in degrees true.

An aerodrome forecast applies only to an area within 8 km of the centre of the aerodrome. Practically, this means the cloud and visibility information contained in the forecast is only applicable to the aerodrome and a small area around it. It should not be used for assessing visibility in the wider geographical area.

 

A TAF can have the terms TEMPO, BECMG, FM, TIL or PROBxx to indicate a change in conditions within the forecast time.

The TEMPO when used in a TAF is used to describe expected temporary fluctuations in the meteorological conditions, that reach or pass specified threshold values and last for a period of less than one hour in each instance. Such fluctuations take place sufficiently infrequently for the prevailing conditions to remain those originally forecast. We have animated a typical TEMPO to show what it would look like.

TREND

A TREND is a forecast, valid for two hours, attached to the end of a METAR (NZWP and NZOH only) and in METAR AUTO for NZAA, NZWN and NZCH only. It states any significant changes from those described in the METAR.

While the TREND is valid it supersedes the aerodrome TAF.

Invercargill

Above mean sea level

TCu

Towering Cumulus

agl

above ground level

Cb

Cumulonimbus

Flight Information Service communications

ATS

Air Traffic Service

Royal New Zealand Air Force

in vicinity of aerodrome Thunderstorm

ATC

Air Traffic Control

VC

in vicinity of aerodrome

Probabilityxx%

TIL

Until

FM

From

Becoming

Temporarily

Routine air report from aircraft in flight

FIR

Flight Information Region

Internet Flight Information Service

VFR

Visual flight rules

Automatic Terminal Information Service

BWR

Basic weather report

New Zealand Flight Information Region

Aerodrome special routine meteorological report

Automatic aerodrome routine meteorological report

Aerodrome routine meteorological report

TAF

Aerodrome forecast

Area forecast

Significant meteorological information