How to Read a TAF
A TAF (Terminal Aerodrome Forecast) is a report that is submitted every 6 hours that is valid for 24-30 hours that forecasts the weather for the destination location. It is used by pilots and dispatchers to obtain forecast weather in order to determine if the destination airport is suitable to land.
Check out your local airport's TAF by entering its 4 digit ICAO number (ie. KJFK) on AviationWeatherCenter.
Quick Overview
A TAF has similar decoding to a METAR, therefore I recommend learning how METAR decoding works before looking at the TAF.
Compared to a METAR, A TAF is separated into "chunks" of time. A TAF is a forecast usually valid for 24-30 hours, and are separated by the "FROM" (FM) code that indicates a significant weather change in that "chunk" of time.
If the weather forecast does not have a lot of changes, the TAF will mostly contain a couple of FROMs. However, there are three conditional codes (TEMPO, PROB, BECMG) that forecasters can add to a TAF in between FROM "chunks" to inform pilots about a temporary change in weather.
For example, there is a FM that is valid for 4 hours from 0000Z to 0400Z. A forecaster spotted a potential fog that might form for a short period at 0200Z, he is able to submit a TEMPO or PROB statement in between the FM chunk.
| Forecast | Abbreviation | Explanation |
| From | FM091930 | Changes expected at 2 digit date, 2 digit hour, 2 digit minute in beginning time Zulu. Indicates significant change. |
| Temporary | TEMPO0920/0922 | Changes expected for less than 1 hour and in total half of the total TAF valid period. |
| Probability | PROB30 1004/1007 | Probability of either 30% or 40% weather happening. |
| Becoming | BECMG 1013/1015 | Change expected in the time period |
Here is an example of a snippet of a TAF from Chicago O'Hare International Airport (KORD) on a windy day. Below I will explain the values line by line.
TAF KORD 151730Z 1518/1624 19015G27KT P6SM VCSH FEW030 SCT040 OVC060
FM152000 19022G35KT P6SM -SHRA BKN025 OVC040
TEMPO 1522/1601 23025G40KT 1 1/2SM TSRA BKN025CB
FM160100 30015G25KT 4SM -SHRA BR BKN008 OVC012
PROB30 1604/1606 01025G35KT 2SM -SNPL
TAF KORD 151730Z 1518/1624 19015G27KT P6SM VCSH FEW030 SCT040 OVC060
| TAF | Message Type, this is a TAF (Can be TAF AMD if there is amend to the previous TAF) |
| KORD | ICAO identifier for Chicago airport |
| 151730Z | TAF was issued at 15th day of the month at 1730 Zulu |
| 1518/1624 | This TAF is valid from 15th day of the month at 1800 Z to 16th day of the month at 2400Z. (30 hours valid total) |
| 19015G27KT | Wind is coming from 190 degrees (True North) at 15 knots with gusts at 27 knots. |
| P6SM | Visibility is more than 6 statue miles (P indicates more than) |
| VCSH | Showers in the vicinity |
| FEW030 | Few clouds at 3000 feet |
| SCT040 | Scattered clouds at 4000 feet |
| OVC060 | Ceiling overcast at 6000 feet (Remember ceilings can only be BKN, OVC, VV) |
FM152000 19022G35KT P6SM -SHRA BKN025 OVC040
| FM152000 | From code that indicates a significant weather change that is valid from 15 of this month from 2000Z to the next FM. Looking at the rest of the FM line, you can see that there is a slight increase in wind and the sky condition worsened. |
| 19022G35KT | Wind is coming from 190 degrees (True North) at 22 knots with gusts at 35 knots. |
| P6SM | Visibility is more than 6 statue miles (P indicates more than) |
| -SHRA | Shower with light rain |
| BKN025 | Ceiling broken clouds at 2500 feet |
| OVC040 | Overcast at 4000 feet |
TEMPO 1522/1601 23025G40KT 1 1/2SM TSRA BKN025CB
| TEMPO 1522/1601 | Temporary change that in the weather from 15th of the month from 2200Z to 16th of the month from 0100Z. Once this period is over, it will revert back to the original valid FM. In this case, once this TEMPO is over, the next FROM will be valid since it starts at 160100. |
| 23025G40KT | Wind is coming from 230 degrees (True North) at 25 knots with gusts at 40 knots. |
| 1 1/12 SM | Visibility is now 1 and one half statue miles. |
| TSRA | Thunderstorm with Rain |
| BKN025CB | Ceiling broken at 2500 ft with cumulonimbus clouds |
FM160100 30015G25KT 4SM -SHRA BR BKN008 OVC012
| FM160100 | From code that indicates a significant weather change that is valid from the 16th of this month at 0100Z. |
| 30015G25KT | Wind is coming from 300 degrees (True North) at 15 knots with gusts at 25 knots. |
| 4SM | Visibility is 4 statue miles |
| -SHRA | Shower with light rain |
| BR | Mist |
| BKN008 | Ceiling broken at 800 feet |
| OVC012 | Overcast at 1200 feet |
PROB30 1604/1606 01025G35KT 2SM -SNPL
| PROB30 1604/1606 | 30% probability that this weather will happen. Valid for 16th of this month from 0400Z to 16th of this month from 0600Z. |
| 01025G35KT | Wind is coming from 010 degrees (True North) at 25 knots with gusts at 35 knots. |
| 2SM | Visibility 2 statue miles |
| -SNPL | light snow and light ice pellets |
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