METAR / AIRMET

Introduction: 
A METAR is a weather reporting format used by pilots to easily identify components of weather in a specific area at any given time. Each part of the METAR identifies a specific part of the current weather in regards to wind speed, precipitation, cloud type, etc. Each METAR contains codes and abbreviations that allow pilots to decode them and gain information that is condensed into a few lines. This allows universal information that is standardized to prevent confusion between pilots. The METAR being decoded in this lab is for KLAF.

(METAR KLAF)

Decoding and Discussion:
The first section of the METAR identifies the exact airport/location it is referring to. The first 4 letters refer to the 4-character ICAO identifier for location/station. The following 7 characters refer to the date and time that the METAR is issued. In this case, it was issued on Thursday, November 14th, at 11:54 AM EST. This section gives pilots information about the location and time first to ensure that they are aware of where and when they study the weather.

(METAR KLAF)

The next section in the METAR contains information regarding the speed and direction of the wind. The first 3 digits refer to the true direction, to the nearest 10 degrees, from which the wind is blowing. For KLAF, at this time, the wind is blowing west-southwest at roughly 240 degrees. The 2 characters following the wind direction refer to the sustained speed. This is the wind speed as it blows constantly throughout that time period. In this case, the wind is blowing at roughly 6-7 knots. If gusts were present, the METAR would contain, for example, "G30KT" meaning there are gusts of winds up 30 knots.

The next four sections on this METAR contains information regarding clouds, visibility, altimeter settings, and temperature. The first section containing "SM" (statute mile) indicates the prevailing visibility. This is the greatest horizontal visibility observed on the horizon. For this METAR, visibility is 10 statute miles. The next section describes the clouds in the specified area. OVC stands for overcast with an AGL of 3200. The third section lets the pilot know the current temperature and dewpoint for KLAF. In this METAR the temperature is 1-degree Celcius indicated by the "01." The dewpoint is indicated by "M05." The "M" stands for minus and the "05" indicates the temperature, so the dewpoint for KLAF would be negative 1-degree Celcius. The final section "A3024" indicates the altimeter settings in inches and hundredths of an inch in mercury. In this METAR the altimeter setting is 30.24 inches Hg.


Decoding an AIRMET 
The AIRMET chosen was for Duluth International Airport. The 4 character ICAO identifier for this airport is KDLH. This METAR was recorded on Novermber 14th, at 1755 UTC. The wind is blowing in the west-southwest direction at roughly 250 degrees. The wind is blowing at a sustained speed of 15 knots with gusts of up to 20 knots. Visibility is 9 statute miles on the horizon. For Duluth there are few clouds at about 1500 AGL. The temperature is negative 3-degrees Celcius and the dewpoint is negative 12-degrees Celcius.

(AIRMET on Skyvector for KDLH)