MetarTaf Decoder

METAR and TAF in plain English, in seconds

Florida Keys Marathon International Airport (KMTH / MTH)

United States · elevation 5 ft AMSL · 24.7260, -81.0514 · Local time: --:--:-- · UTC time: --:--:--

About Florida Keys Marathon International Airport

Florida Keys Marathon International Airport is an airport with the ICAO code KMTH and the IATA code MTH. Country: United States. Nearest settlement listed in the database: Marathon. OurAirports classifies it as a medium-sized airport. Its ICAO code starts with the KM prefix, which marks airports in United States. The four-letter code KMTH is used in flight operations and weather reports, while the three-letter IATA code MTH is used for ticketing and baggage handling. The airport reference point sits at 24°43'34"N, 81°03'05"W, at an elevation of 5 ft (2 m) above sea level. The applicable time zone is America/New_York.

Satellite view of KMTH

Aerial imagery showing the runway and apron layout - the zoom is matched to the longest runway.

Open the satellite view in Google Maps

Runways of KMTH

ThresholdCourseLengthWidthSurface
0770°1,526 m (5,008 ft)30 m (100 ft)asphalt
25250°

The course is derived from the runway designator (number × 10), not from a survey - the actual magnetic bearing can differ by a few degrees.

Declared distances (TORA, TODA, ASDA, LDA) are published in the national AIP - they are not part of this table.

Climate at Florida Keys Marathon International Airport - statistics from METAR reports

What the METAR reports from KMTH for 2023-2025 show - counted hour by hour.

We computed these statistics from 26,274 METAR reports issued by KMTH in 2023-2025. VFR conditions prevailed 94% of the time, MVFR 5% and IFR or LIFR 1%. Best month for VFR flying: July (97% of hours VFR). Most IFR and LIFR hours: January (4%).

IFR and LIFR conditions are rare here at any time of day.

Fog (FG) was reported on 4.7 days a year on average, most often in August. Thunderstorms (TS) occurred on 32 days a year on average, and snowfall practically never.

The wind most often blows from E (90°) - 19% of reports. Calm (0 kt) made up 7% of reports, and gusts of 25 kt or more appeared in 3%. Warmest month: July (average high 32.8 °C); coldest: January (average low 19.0 °C).

Year

Selected period in numbers: 2023-2025

VFR hours
94%
IFR/LIFR hours
1%
Avg high
29.3 °C
Avg low
24.7 °C
Fog days
4.7
Thunderstorm days
32
Snow days
0
Prevailing wind
E · 19%
Gusts ≥ 25 kt
3%

Day counts are for the selected period (for all years - the yearly average).

Flight categories month by month
Bar chart: share of VFR, MVFR, IFR and LIFR hours in each month0%25%50%75%100%January: VFR 87%, MVFR 9%, IFR 3%, LIFR 1%JanFebruary: VFR 94%, MVFR 6%, IFR <1%, LIFR <1%FebMarch: VFR 96%, MVFR 4%, IFR <1%, LIFR 0%MarApril: VFR 96%, MVFR 4%, IFR <1%, LIFR <1%AprMay: VFR 95%, MVFR 5%, IFR <1%, LIFR <1%MayJune: VFR 95%, MVFR 4%, IFR 1%, LIFR <1%JunJuly: VFR 97%, MVFR 3%, IFR <1%, LIFR <1%JulAugust: VFR 95%, MVFR 4%, IFR <1%, LIFR <1%AugSeptember: VFR 94%, MVFR 5%, IFR 1%, LIFR <1%SeptOctober: VFR 93%, MVFR 6%, IFR 1%, LIFR <1%OctNovember: VFR 95%, MVFR 4%, IFR 1%, LIFR <1%NovDecember: VFR 92%, MVFR 5%, IFR 2%, LIFR 1%Dec
  • VFR 94%
  • MVFR 5%
  • IFR 1%
  • LIFR <1%
Temperature month by month
Chart: average daily high and low temperature in each month0°5°10°15°20°25°30°35°January: 19.0 … 24.6 °C2519JanFebruary: 22.4 … 27.3 °C2722FebMarch: 22.2 … 27.4 °C2722MarApril: 23.8 … 28.5 °C2824AprMay: 26.0 … 30.6 °C3126MayJune: 26.9 … 31.5 °C3127JunJuly: 28.2 … 32.8 °C3328JulAugust: 27.9 … 32.6 °C3328AugSeptember: 27.3 … 32.0 °C3227SeptOctober: 25.2 … 29.5 °C3025OctNovember: 22.9 … 27.2 °C2723NovDecember: 20.8 … 25.1 °C2521Dec

The top of each bar is the average daily high, the bottom the average daily low (usually around dawn), in °C.

Wind rose: how often the wind blows from each of 16 directions5%10%15%20%N: 4%NNE: 6%NE: 7%ENE: 9%E: 19%ESE: 11%SE: 7%SSE: 5%S: 4%SSW: 2%SW: 1%WSW: 1%W: 1%WNW: 2%NW: 3%NNW: 3%NNNENEENEEESESESSESSSWSWWSWWWNWNWNNWE 19%

Wind rose

  • 1-10 kt
  • 11-20 kt
  • over 20 kt
  • calm: 7%

Most often: E - 19% of reports. Each petal shows the direction the wind blows from (as in METAR) - the longer it is, the more often. Colour shows wind speed.

Month by month

MonthAvg high °CAvg low °CVFRIFR/LIFRFog daysThunderstorm daysSnow days
January24.619.087%4%0.30.30
February27.322.494%<1%0.300
March27.422.296%<1%01.30
April28.523.896%<1%0.310
May30.626.095%<1%02.70
June31.526.995%1%0.740
July32.828.297%<1%040
August32.627.995%1%1.7100
September32.027.394%1%06.30
October29.525.293%1%0.320
November27.222.995%1%0.700
December25.120.892%3%0.30.30

Temperatures are averages of daily highs and lows. Day counts are the average per month over the period.

More in the METAR Academy: VFR, MVFR, IFR, LIFR flight categories, fog in METAR

Source: routine METAR reports from the Iowa Environmental Mesonet archive (Iowa State University), 2023-2025. Flight categories use the FAA thresholds, widely used as a convention. A day counts when it has at least 12 reports. These are statistics of past conditions - not a forecast or a substitute for a pre-flight briefing.

Runways at KMTH

According to OurAirports data (compiled from AIP and FAA sources), Florida Keys Marathon International Airport has one runway: 07/25 - 1,526 m long (5,008 ft), 30 m wide, asphalt surface.

Runway headings and wind

The thresholds are oriented as follows: 07/25 on 70° and 250° magnetic. A threshold designator is its magnetic heading divided by ten (ICAO Annex 14), so the runway axis can be read straight off the numbers.

For the 07/25 axis, wind from the south (around 160°) or from the north (around 340°) blows perpendicular to the runway and produces the largest crosswind component. Wind from around 70° or 250° acts along the runway, as a headwind or a tailwind. The decoder on this page computes those components automatically from the current METAR.

METAR and TAF for KMTH

Weather reports for Florida Keys Marathon International Airport are published under the ICAO code KMTH. A METAR is an observation of current conditions, usually issued every 30 or 60 minutes; a TAF is a forecast for the airport area, typically covering 9 to 30 hours.

The decoder breaks the KMTH report down into its parts: wind direction and speed including gusts and variability, visibility (including CAVOK and directional minimum visibility), weather phenomena by WMO code, cloud layers with their bases, temperature and dew point, QNH pressure, and the resulting flight category - VFR, MVFR, IFR or LIFR - using FAA thresholds.

Not every airport issues its own reports; many smaller airfields have no weather station. If no current data is available for KMTH, check the nearby airports listed below.

Reports always use UTC (the Z suffix). The America/New_York zone is GMT-05:00 in winter and GMT-04:00 in summer - that is the shift to apply to the time in the report to get local time at the airport.

The closest airports in the database, measured in a straight line from the reference point, are Big Pine Sands STOLGround (Big Pine Key, Florida) (KBPD, 34 km), Naval Air Station Key West/Boca Chica Field (KNQX, 67 km), Key West International Airport (KEYW, 74 km). When no report is available for KMTH, they usually give the best approximation of conditions in the area.

METAR Academy

Something unclear in the KMTH report?

Step-by-step guides - with examples, charts and calculators.

How to read a METARHow to read a TAFVFR/IFR flight categoriesAll guides →

Advertisement

ICAO4U

Pass your ICAO Aviation English exam - 100% online

ICAO Level 4, 5 or 6 for PPL(A)/CPL(A)/ATPL(A): aviation vocabulary, radio phraseology, pronunciation and standard/emergency flight scenarios. Buy through this link and get a 10% discount.

Check ICAO4U

Nearby airports

Looking for a report from a specific day?

The METAR archive for KMTH goes back to 18/03/1988. Pick a date and see every observation from that day.

Open METAR history →

Live weather from KMTH on your website

Run a flying club, a training organisation or an airfield website? Embed a ready-made panel with the current KMTH METAR - flight category, wind, visibility, temperature and pressure, refreshed automatically. The configurator lets you pick language, theme and units; you paste the code once.

Configure the widget Free, no account and no display limit.