NWS Marquette Aviation:TAFs

NWS Marquette TAF Sites

KIWD

Runway	Length	Width
09/27	6501'	130'

Airport Minimums
Landing	Ceiling 200ft; Visibility 1/2SM
Alternate	Ceiling 900ft; Visibility 2SM

KCMX

Runway	Length	Width
07/25 (not used in Winter)	5196'	100'
13/31	6501'	150'

Airport Minimums
Landing	Ceiling 200ft; Visibility 1/2SM
Alternate	Ceiling 600ft; Visibility 2SM

KSAW

Runway	Length	Width
01/19	12366'	150'

Airport Minimums
Landing	Ceiling 200ft; Visibility 1/2SM
Alternate	Ceiling 600ft; Visibility 2SM

Site Climatology
Ceilings & Visibility	Winds	Snow

TAF Tools

Regional TAF Sites
Minnesota	Wisconsin	Michigan

Individual TAF

Flight Criteria

Flight Categories
Flight Category	Ceiling (feet)	Visibility (SM)
VLIFR	< 200 and/or	< ½
LIFR	< 500 and/or	< 1
IFR	≥ 500 to < 1,000 and/or	≥ 1 to < 3
MVFR	≥ 1,000 to ≤ 3,000 and/or	≥ 3 and ≤ 5
VFR	> 3,000 and	> 5

Critical Amendment Critera - CAC
Flight Category	Impact
MVFR	≤ 3000 ft and/or ≤ 5 sm
Must File Alternate	< 2000 ft and/or < 3 sm
IFR	< 1000 ft and/or < 3 sm
Alternate Landing Minimums (airport dependent)	600 ft and/or 2 sm
Airfield Landing Minimums (airport dependent)	200 ft and/or ½ sm

TAF Background

Concept

The NWS aviation terminal aerodrome forecast (TAF) is a concise statement of the expected meteorological conditions significant to aviation to impact an airport during the 24-hour forecast period. An airport is defined as the area within 5 statute miles of the center of an airport's runway complex.

NWS Marquette issues TAFs for the Marquette Sawyer International Airport (SAW), Houghton County Memorial Airport (CMX), and Gogebic-Iron County Airport (IWD) in Ironwood. The aviation forecaster at NWS Marquette maintains a watch of weather conditions at these locations and issues amended forecasts in addition to the scheduled TAFs when observed or expected conditions meet amendment criteria for the specified forecast elements and are expected to persist, or in the forecaster's judgment, the TAF is unrepresentative of current or expected weather.

Format

The necessary components of a TAF include a location identifier group, a date/time of forecast origin, a valid period date/time group, forecast group(s) for the forecast period, and an end of message designator (=) trailing the last forecast group.

Content

The forecast elements are entered into the body of the initial forecast period and are followed by any succeeding time-divider (FM), forecast change (TEMPO), and probability forecast (PROB30) group(s). The order in which these forecast elements are encoded (if they are necessary) is as follows: wind, visibility, significant weather, cloud (or vertical visibility into a surface-based obscuration), and non-convective low-level wind shear.

Issuance

Every 6 hours, NWS Marquette issues scheduled SAW, CMX and IWD TAFs, valid for 24 hours:

Issued	Valid
2320-2340Z	00Z-24Z
0520-0540Z	06Z-06Z
1120- 1140Z	12Z-12Z
1720-1740Z	18Z-18Z

Examples:

Scheduled TAF:

FTUS43 KMQT 241730
TAFSAW
TAF
KSAW 241730Z 2418/2518 18005KT 5SM HZ BR SCT045
     FM241930 14010KT P6SM VCTS SCT035CB
      TEMPO 2420/2422 BKN025
     FM242200 16015G25KT P6SM VCTS BKN025CB
      TEMPO 2422/2502 VRB25G40KT 1SM +TSRAGR BKN010CB OVC020
     FM250200 30012KT 5SM -SHRA OVC025 WS020/23040KT
      PROB30 2502/2504 2SM TSRA BR BKN010CB OVC020
     FM251400 32012G22KT P6SM BKN040=

Unscheduled TAF: Amendment

FTUS43 KMQT 211125 AAA
TAFIWD
TAF AMD
KIWD 211233Z 2113/2212 20010KT 5SM -SN OVC015
TEMPO 2112/2115 P6SM SCT015 OVC030
FM220500 22008KT 5SM -SN BR BKN025 OVC040=

NOTE: This is the first amendment to the 2112/2212 TAF issued at 1125Z, evident by the date/time of forecast origin and the contraction "AAA". Subsequent amendments will labeled as "AAB", "AAC", "AAD", and so on.

Unscheduled TAF: Correction

The contraction "CCA" is used for any TAF that must be corrected. Subsequent corrections will labeled as "CCB", "CCC", "CCD", and so on.