It was a Thursday morning at Centennial Airport. My CFI had walked back to the FBO to grab a headset cable, and I was standing at the weather kiosk with exactly the amount of time it takes to fill a small coffee cup. The METAR for KAPA was right there on the screen. I knew what a METAR was. I had read about them. I had passed the knowledge test. But standing there trying to actually parse the string in under thirty seconds, I realized I was treating it like a foreign language I had memorized from flashcards and never actually spoken.

The CFI came back. I said the weather looked okay. She asked me what the wind was. I said it looked fine. She asked again - with numbers. I had no answer, because I had been looking at the METAR without actually reading it.

That moment is the reason this post exists. Not to walk through abstract definitions, but to build a real decode workflow for real preflight moments: standing at a kiosk, loading a briefing on your phone in the parking lot, or sitting in the run-up area wondering what that ceiling actually means for your solo.

Why You Cannot Use a Briefing App as a Crutch

ForeFlight and Garmin Pilot will translate a METAR into color-coded categories. Green means VFR, yellow means MVFR, red means IFR. Those categories are useful for scanning. They are not sufficient for deciding.

On your solo, and especially on your checkride, you will be handed a raw METAR and asked to interpret it. More practically, the app category doesn't tell you the wind is from 250 at 18 gusting 28, which matters when Runway 17L at KAPA puts a direct crosswind on you at the high end of your personal limits. The category doesn't tell you the temperature-dewpoint spread is 3 degrees and narrowing, which tells you fog is a real possibility on your return leg. The category doesn't tell you the remarks section has a thunderstorm moving toward the field from the west.

The FAA Aviation Weather Handbook (FAA-H-8083-28) is the primary reference for pilots on interpreting aviation weather products, and it is explicit: understanding raw METAR and TAF text is a required skill, not an optional upgrade. The app is a layer on top of that skill, not a replacement for it.

The goal for local VFR flights is to be able to look at a raw METAR and TAF and make a Go/No-Go decision in under 60 seconds. This post builds that skill.

The METAR Decode Key

A METAR is an aviation routine weather observation. It is issued once per hour at most reporting stations, or more frequently as a SPECI (special observation) when conditions change significantly. The NWS TAF/METAR Key Card is a one-page reference that covers every field - print it and keep it in your flight bag until you have the format cold.

Here is a realistic summer METAR for KAPA, the kind you might see on a July afternoon along the Front Range:

METAR KAPA 221853Z 26018G28KT 10SM FEW055 BKN090 28/10 A2992 RMK AO2 PK WND 27032/1822 WSHFT 1845 CB DSNT W PRESFR

Let's decode it field by field.

Report Type

METAR tells you this is a routine hourly observation. If the type were SPECI, the station issued it outside the normal cycle because conditions changed - visibility dropped, a thunderstorm arrived, winds shifted. A SPECI at the top of your briefing deserves a second look before you go.

ICAO Station

KAPA is the four-letter ICAO identifier for Centennial Airport, Englewood, Colorado. Every reporting station in the contiguous U.S. starts with K. Canadian stations start with C, and so on. If you're ever confused about which airport a METAR belongs to, aviationweather.gov lets you look up stations by identifier or by clicking a map.

Date and Time in Zulu

221853Z means the 22nd day of the month, at 1853 Zulu (UTC). That is the moment the observation was taken. Always confirm the METAR is current - an observation more than an hour old may not reflect present conditions. In Colorado during summer, conditions can change faster than that.

Wind

26018G28KT is the wind: 260 degrees true at 18 knots, gusting to 28 knots. The format is always three digits for direction, then speed, then G for gust followed by the gust speed, then KT for knots (or MPS for meters per second at international stations).

A few variations to know:

  • VRB in place of direction means the wind direction is variable and no single direction dominates - for example, VRB04KT. This often shows up during calm or convective conditions.
  • If the direction varies by 60 degrees or more and the speed is above 6 knots, you may see a variable group like 220V300 appended after the primary wind group, showing the range of directions.
  • Wind direction in a METAR is magnetic only by convention of ATC use, but technically METARs report in degrees true. In practice for your preflight, compare it against the runway heading to assess crosswind component.

Visibility

10SM means the prevailing visibility is 10 statute miles. Visibility in U.S. METARs is always in statute miles (SM). If visibility drops below 3/4 of a mile, it can be reported in fractions (for example, 1/4SM).

At very low visibility, especially near a runway, you may see a Runway Visual Range (RVR) group instead of or in addition to the SM figure. RVR is reported in feet and looks like R35L/4000FT, meaning Runway 35 Left, RVR 4,000 feet. RVR matters most for IFR operations, but as a student pilot it is worth knowing what the format means.

Weather Phenomena

Our sample METAR doesn't have a weather phenomena group, which means no significant precipitation or obscuration at the time of observation. When the group is present, it follows a structured format covered in depth in the FAA Aviation Weather Handbook:

  • Intensity prefix: minus sign (-) for light, no prefix for moderate, plus sign (+) for heavy. VC means in the vicinity (within 5 to 10 miles of the station but not at it).
  • Descriptor: TS for thunderstorm, SH for shower. These modify the precipitation type that follows.
  • Precipitation: RA (rain), SN (snow), GR (hail), DZ (drizzle), PL (ice pellets), GS (small hail or snow pellets).
  • Obscuration: FG (fog, visibility below 5/8 mile), BR (mist, visibility 5/8 to 6 miles), HZ (haze), FU (smoke), DU (dust).

So -TSRA means light thunderstorm with rain. +SHRA means heavy rain shower. VCTS means a thunderstorm is in the vicinity but not over the field. That last one is the one that gets student pilots - a VCTS in the remarks means you have active convection close enough to matter.

Sky Condition

FEW055 BKN090 means a few clouds at 5,500 feet AGL and a broken ceiling at 9,000 feet AGL. The numbers in sky condition groups are always in hundreds of feet AGL - so 055 is 5,500 feet, 090 is 9,000 feet.

The coverage codes are defined in the AIM Chapter 7:

  • FEW: 1/8 to 2/8 sky coverage
  • SCT (Scattered): 3/8 to 4/8 sky coverage
  • BKN (Broken): 5/8 to 7/8 sky coverage - this is a ceiling
  • OVC (Overcast): 8/8 sky coverage - this is a ceiling
  • CLR or SKC: Clear, no clouds. CLR is used by automated stations (no clouds detected below 12,000 feet). SKC is used by human observers. CAVOK is an international term meaning ceiling and visibility OK, but it is rarely used in U.S. METARs.

The ceiling is the lowest broken or overcast layer. Basic VFR in controlled airspace requires a ceiling of at least 1,000 feet and 3 statute miles visibility. Your personal minimums as a student should be higher than that.

Temperature and Dewpoint

28/10 means temperature 28 degrees Celsius, dewpoint 10 degrees Celsius. The temperature-dewpoint spread here is 18 degrees, which is wide enough that fog and low visibility from moisture are not immediate concerns. When that spread narrows to 5 degrees or less, fog becomes a real possibility.

The spread also gives you density altitude context. At KAPA (field elevation 5,883 feet MSL), a temperature of 28 Celsius puts your density altitude well above 8,000 feet on a standard July afternoon. M in front of either number means below zero - M03 means minus 3 degrees Celsius.

Altimeter

A2992 means the altimeter setting is 29.92 inches of mercury. You set this in your Kollsman window before every flight. It is not the temperature, it is not the dewpoint, and it is not related to field elevation - it is the local sea-level pressure equivalent, used to calibrate your altimeter.

Remarks (RMK) - the Section Most Students Skip

Everything after RMK is the remarks section, and it is where a lot of operationally important information lives.

In our METAR: AO2 PK WND 27032/1822 WSHFT 1845 CB DSNT W PRESFR

  • AO2 means this is an automated station with a precipitation discriminator (it can tell rain from snow). AO1 stations cannot discriminate precipitation type - an important caveat covered below.
  • PK WND 27032/1822 means the peak wind gust since the last observation was 32 knots from 270 degrees, at 1822Z. That gust is higher than what the current wind group shows - worth knowing.
  • WSHFT 1845 means a wind shift occurred at 1845Z, likely associated with a frontal passage or convective outflow.
  • CB DSNT W means cumulonimbus clouds (thunderstorms) are distant to the west. This is operationally significant even though they're not over the field yet.
  • PRESFR means the pressure is falling rapidly (at least 0.06 inches of mercury in the last three hours). Rapid pressure falls are associated with approaching low pressure systems or strong convective activity.

If you cut off your METAR decode at the altimeter setting, you missed a wind shift, a distant thunderstorm, and a falling pressure trend. That's the RMK section doing exactly what it's supposed to do.

TAF-Specific Fields

A Terminal Aerodrome Forecast (TAF) uses most of the same field formats as a METAR but adds forecast-specific groups. TAFs at most airports cover a 24-hour period, with some major airports issuing 30-hour TAFs. They are updated four times daily.

A realistic TAF for KAPA on a summer afternoon might look like this:

TAF KAPA 221720Z 2218/2318 26015G22KT P6SM FEW060 BKN110
FM222000 27018G28KT 8SM VCTS SCT050CB BKN080
TEMPO 2220/2222 5SM +TSRA BKN030CB
FM230000 20008KT P6SM SCT060
BECMG 2306/2308 VRB05KT P6SM SKC

Time Period

2218/2318 is the valid period: from the 22nd at 1800Z to the 23rd at 1800Z. The format is always two-digit day and four-digit hour for both the start and end.

FM (From) Groups

FM222000 means from the 22nd at 2000Z, conditions are expected to change to what follows. FM groups describe a relatively rapid, distinct change in conditions - think frontal passage or sea breeze onset. Everything after an FM group is the new expected condition until the next FM or the end of the valid period.

BECMG (Becoming)

BECMG 2306/2308 means conditions are expected to gradually change to what follows between 0600Z and 0800Z on the 23rd. Unlike FM, the change is spread across the time window - you can't assume the new conditions arrive at the start of it. This is the group students most often misread as an FM.

TEMPO (Temporary)

TEMPO 2220/2222 means temporary conditions - expected to last less than one hour at a time and occurring during less than half of the indicated period - between 2000Z and 2200Z on the 22nd. TEMPO groups overlay the base forecast; the base conditions are still expected to prevail, with these intermittent deviations. A TEMPO with +TSRA BKN030CB means brief heavy thunderstorm and rain with a broken ceiling at 3,000 feet - conditions that could close the airport temporarily even if the surrounding forecast looks fine.

PROB30 and PROB40

These probability groups indicate a 30% or 40% chance of the described conditions. PROB40 means there's a 40% probability the conditions listed will occur during the stated period. You will not see PROB50 or higher - forecasters use FM or TEMPO for those higher-confidence changes. PROB30 is not used in the first 9 hours of a TAF. These groups are covered in detail in the NWS TAF/METAR Key Card.

The Decode Then Decide Workflow

This is the core of the post. It is a sequence that takes under 60 seconds for a local flight once you have practiced it enough times that the decode itself is automatic.

  1. Read the METAR out loud once. Not in your head - out loud. This forces you to actually process each field rather than pattern-match on the familiar parts and skip the unfamiliar ones. Say "winds two-six-zero at eighteen gusting twenty-eight" and you will catch the gust. Say "remarks: CB distant west, pressure falling rapidly" and you will not forget it.
  2. Match against your personal minimums. Is the ceiling above your minimums? Is the wind within your crosswind comfort zone, including the gusts? Is the temperature-dewpoint spread wide enough that you're not going to fly into fog on the return leg? These answers should take about ten seconds once the METAR is decoded.
  3. Read the TAF for your flight window. Find your departure time and your expected return time. What does the TAF show for that window? What is the base forecast? Are there any FM groups that shift conditions within your window?
  4. Look for the trend - improving or deteriorating? Is the ceiling rising or dropping across the TAF time period? Is the visibility increasing or decreasing? A deteriorating trend changes the risk profile of the flight even if current conditions are acceptable.
  5. Look for TEMPO or PROB groups that overlap your flight time. A TEMPO with a 3,000-foot broken ceiling during your flight window is not just a footnote - it is a possible scenario you need to have a plan for. What will you do if conditions drop temporarily? Where will you divert? Is there a nearby airport you can land and wait it out?
  6. Cross-reference with the Area Forecast Discussion. The Area Forecast Discussion (AFD) at aviationweather.gov is written by the local NWS forecasters in plain language. It explains the reasoning behind the TAF - why they expect those thunderstorms, how confident they are in the timing, what they're watching. The AFD is one of the most useful free tools available to pilots and one of the least used by students.
  7. Make the call. Go, No-Go, or Go with a specific out. Don't hedge indefinitely. A No-Go decision made confidently at the FBO is a better outcome than a Go decision made under pressure with doubts you didn't resolve.

The KAPA Example - Walking Through It

Let's use the METAR and TAF from above. It is 1900Z on a Tuesday in July. You have a solo cross-country planned, departing KAPA at 2015Z, returning by 2130Z.

Step 1 - Read the METAR out loud: "Centennial Airport, 22nd at 1853 Zulu. Winds two-six-zero at eighteen gusting twenty-eight knots. Visibility ten statute miles. Few clouds at five thousand five hundred, broken ceiling at nine thousand. Temperature twenty-eight, dewpoint ten. Altimeter two-niner-niner-two. Remarks: automated station with precip discriminator. Peak wind thirty-two knots from two-seven-zero at 1822. Wind shift at 1845. Cumulonimbus distant to the west. Pressure falling rapidly."

Step 2 - Personal minimums check: The ceiling at 9,000 feet is fine for VFR. The wind is a crosswind component issue depending on your runway - 260 degrees at 18 gusting 28 on Runway 17L puts a significant crosswind on you, and that 28-knot gust peak was 32 knots twenty minutes ago. The temperature-dewpoint spread is 18 degrees, so fog is not a near-term concern. The CB distant west and pressure falling rapidly are flags.

Step 3 - TAF for the flight window: You're flying 2015-2130Z. The FM222000 group takes effect at 2000Z, right as you're departing. That group calls for winds 270 at 18 gusting 28, visibility 8SM with VCTS, scattered cumulonimbus at 5,000 feet, broken ceiling at 8,000. The base forecast is already borderline.

Step 4 - Trend: The trend is deteriorating. The 1800Z base forecast was better than the 2000Z FM group. The TAF shows conditions worsening through your flight window.

Step 5 - TEMPO check: The TEMPO 2220/2222 group overlaps your planned return at 2130Z. +TSRA with a BKN030CB means a possible broken ceiling at 3,000 feet with heavy thunderstorm rain during your return window. That is a hard No-Go condition if it materializes.

Step 6 - AFD: The AFD for Denver/Boulder would likely be calling for an active afternoon convective cycle with isolated to scattered storms along the Palmer Divide and west suburbs, timing uncertain. That uncertainty is exactly why you check it - the TAF says TEMPO, but the AFD might say the forecasters are watching an earlier trigger time.

Step 7 - The call: No-Go, or delay until the convective cycle passes. The combination of a deteriorating TAF trend, TEMPO thunderstorm conditions overlapping the return window, CB distant west at departure time, and rapidly falling pressure makes this a flight to reschedule. The airplane will be there tomorrow morning when the convective outlook is clear and the winds are light.

Common Student Traps

These are the mistakes that show up consistently in student pilots who know what a METAR is but haven't built the decode-and-decide habit yet.

  • Ignoring the RMK section. The remarks section often contains the operationally critical information - CB nearby, wind shift, pressure trend, peak gusts. Skipping it is like reading the subject line of an email and deciding you've read the email.
  • Missing TEMPO groups that overlap the flight window. A TEMPO doesn't guarantee the bad conditions, but it puts them on the table. If you're not actively checking whether any TEMPO or PROB group lands inside your departure-to-return window, you're not fully reading the TAF.
  • Confusing BECMG and FM. FM means conditions change to the new state relatively quickly. BECMG means the transition happens gradually over the window. If you read a BECMG as an FM, you may think conditions change earlier or later than the forecaster intended.
  • Confusing the altimeter with temperature or pressure altitude. The altimeter setting is the local pressure reduced to sea level. It is not the field elevation. It is not the temperature. Set it in the Kollsman window every flight, and cross-check it against the published field elevation when you're on the ground to verify your altimeter is reading accurately.
  • Trusting AO1 automated stations near convection. An AO1 station (no precipitation discriminator) cannot tell rain from hail. If you're flying near convection and the closest reporting station is an AO1 automated site, it may not detect hail or distinguish between light rain and a convective downpour. Supplement with pilot reports (PIREPs) and NEXRAD radar when convection is in the area. The FAA Aviation Weather Handbook covers automated station limitations in detail.

Graphical vs. Raw Text on aviationweather.gov

The graphical products at aviationweather.gov - the flight category map, the graphical METAR overview, the SIGMET/AIRMET display - are excellent for situational awareness during initial planning. They let you see at a glance where VFR conditions give way to IFR, where AIRMETs are active, and whether convection is affecting a broad region.

The graphical view is not sufficient for your final Go/No-Go. For that, you need the raw text METAR and TAF, the Area Forecast Discussion, and any current PIREPs for your route. The graphical display collapses information - it shows you a green dot over KAPA but doesn't show you the CB DSNT W in the remarks or the TEMPO +TSRA in the TAF.

A good workflow: start with the graphical overview to understand the broad picture, then drill into raw text products for the specific airports on your route. The AIM Chapter 7 covers the full range of aviation weather services and sources available to pilots, and it is worth a thorough read before your first solo cross-country.

For KAPA specifically, cross-referencing with the Denver, Colorado NEXRAD radar on aviationweather.gov during summer afternoons gives you the convective picture that no METAR can fully capture - you can see the storm cells building over the mountains, tracking east, and timing their arrival at the field in a way that a text TAF can only approximate.

The Bottom Line

A METAR is a compressed sentence describing what the sky is doing right now at one specific point. A TAF is a compressed paragraph describing what the sky is expected to do over the next 24 hours at that same point. Both of them are written in a format you can fully decode in under a minute once you have practiced it enough times that the fields are automatic.

The workflow - decode the METAR out loud, check your personal minimums, read the TAF for your window, find the trend, find the TEMPO and PROB groups, read the AFD, make the call - is not complicated. It is just a habit. Like any preflight item, it takes repetition before it becomes fast and reliable.

Print the NWS TAF/METAR Key Card and decode five METARs from KAPA before your next lesson. Use aviationweather.gov for the raw text and the Area Forecast Discussion. Read the FAA Aviation Weather Handbook Chapter on METARs and the relevant section of the AIM Chapter 7 once through. By the time you're standing at that kiosk with sixty seconds while your CFI gets coffee, you'll have the answer before she's back.