Bozeman Yellowstone International to Great Falls International BZN → GTF
103 nautical miles (118 statute miles) north on a straight line, true course 355°, about 342° magnetic at the departure end (variation 13E). At 120 knots that is 33 min at the quickest height in today's winds (30,000 ft, a 69-knot tailwind), arriving about 8:42 pm MDT (02:42 UTC), after sunset at the destination. Right now BZN is IFR, wind calm; GTF is low IFR, wind from the north (010°) at 11 knots. For planning, not a briefing: the legal preflight briefing comes from Flight Service (1-800-WX-BRIEF) or the FAA's own tools. Airlines fly this pair: 783 flights in the DOT's last twelve reported months, the route's page.
The route the straight line, the warnings crossed, restrictions, pilot reports and the airports along the way · click a mark for its words
Green, blue, red and purple airport dots are the flying conditions reported there now (VFR, marginal VFR, IFR, low IFR); grey means no report. Red areas are SIGMETs, orange areas AIRMETs, hatched red areas temporary flight restrictions. Map tiles: OpenFreeMap, data © OpenStreetMap contributors.
Warnings the route crosses SIGMETs and AIRMETs whose area the line passes through or comes within 25 nm of
- AIRMET SIERRA 4E: low cloud or poor visibility (IFR conditions) (due to ceilings below 1,000 ft, visibility below 3 miles, precipitation, mist). Over the whole route.
- AIRMET TANGO 4W: moderate turbulence above 18,000 ft from 18,000 ft to 36,000 ft. Over the whole route.
- AIRMET TANGO 4W: moderate turbulence below 18,000 ft up to 18,000 ft. Near the route, at the departure end.
- AIRMET SIERRA 1E: mountains obscured by cloud (due to mountains obscured by clouds, precipitation, mist). Over the whole route.
- AIRMET ZULU 2C: moderate icing up to 16,000 ft. Over the last 56 nm of the route.
A SIGMET warns of weather hazardous to all aircraft; an AIRMET of weather that matters to small aircraft and to flying without instruments. "From 60 to 180 nm out" is measured along the route from BZN.
Pilot reports along the route within 50 nm of the line, last three hours, the serious ones first
- E75L descending, 0 nm northwest, 7:04 pm MDT (01:04 UTC): remarks: had the airport in sight at 400-500FT above ground. At the departure end, 0 nm northwest of the line.
as filed, and in English
BZN UA /OV BZN/TM 0104/FLDURD/TP E75L/RM HAD THE AIRPORT IN SIGHT AT 400-500FT AGL
- Report
- a routine report filed through BZN
- Where
- over BZN
- Time
- 01:04 UTC
- Height
- during the descent
- Aircraft
- E75L
- Remarks
- had the airport in sight at 400-500FT above ground
- B737 descending, 0 nm northwest, 6:28 pm MDT (00:28 UTC): scattered clouds above 8,000 ft, fog, snow, remarks: broke out about 100FT above mins. At the departure end, 0 nm northwest of the line.
as filed, and in English
BZN UA /OV BZN/TM 0028/FLDURD/TP B737/SK SCT080/WX 1/2SM SN FG/RM BROKE OUT ABOUT 100FT ABOVE MINS
- Report
- a routine report filed through BZN
- Where
- over BZN
- Time
- 00:28 UTC
- Height
- during the descent
- Aircraft
- B737
- Sky
- scattered clouds from 8,000 ft
- Weather
- 1/2SM, snow, fog
- Remarks
- broke out about 100FT above mins
- B738 at 24,000 ft, 28 nm west, 5:13 pm MDT (23:13 UTC): remarks: snow top flight level at 24,000 ft zlc. 9 nm along the route, 28 nm west of the line.
as filed, and in English
BZN UA /OV BZN270030/TM 2313/FL240/TP B738/RM SN TOP FL 240 /ZLC
- Report
- a routine report filed through BZN
- Where
- 30 nm west (270°) of BZN
- Time
- 23:13 UTC
- Height
- at 24,000 ft
- Aircraft
- B738
- Remarks
- snow top flight level at 24,000 ft zlc
Winds aloft along the route, and the time en route the forecast for use 20:00–03:00 UTC · at 120 knots true airspeed
The westbound cruising heights for this course (VFR: even thousands plus 500 ft; above 18,000 ft the forecast levels), with the wind averaged along the line from the 2 forecast points nearest it (DLN, GTF). A plus sign is a headwind, a minus sign a tailwind.
| Height | Average wind | Head- or tailwind | Temperature | Ground speed | Time en route | Arrival |
|---|---|---|---|---|---|---|
| 4,500 ft | 070° at 21 kt | +5 kt | 115 kt | 54 min | 9:03 pm MDT (03:03 UTC) | |
| 6,500 ft | 070° at 20 kt | +5 kt | 115 kt | 54 min | 9:03 pm MDT (03:03 UTC) | |
| 8,500 ft | 080° at 15 kt | +2 kt | -3 °C | 118 kt | 52 min | 9:01 pm MDT (03:01 UTC) |
| 10,500 ft | 100° at 8 kt | −2 kt | -5 °C | 122 kt | 51 min | 9:00 pm MDT (03:00 UTC) |
| 12,500 ft | 160° at 7 kt | −7 kt | -5 °C | 127 kt | 49 min | 8:58 pm MDT (02:58 UTC) |
| 14,500 ft | 170° at 14 kt | −14 kt | -9 °C | 134 kt | 46 min | 8:55 pm MDT (02:55 UTC) |
| 16,500 ft | 180° at 21 kt | −21 kt | -12 °C | 141 kt | 44 min | 8:53 pm MDT (02:53 UTC) |
| 18,000 ft FL180 | 180° at 27 kt | −27 kt | -14 °C | 147 kt | 42 min | 8:51 pm MDT (02:51 UTC) |
| 24,000 ft FL240 | 200° at 55 kt | −50 kt | -23 °C | 170 kt | 36 min | 8:45 pm MDT (02:45 UTC) |
| 30,000 ft FL300 | 210° at 80 kt | −69 kt | -37 °C | 189 kt | 33 min | 8:42 pm MDT (02:42 UTC) |
| 34,000 ft FL340 | 220° at 84 kt | −59 kt | -43 °C | 179 kt | 35 min | 8:44 pm MDT (02:44 UTC) |
| 39,000 ft FL390 | 230° at 74 kt | −42 kt | -46 °C | 162 kt | 38 min | 8:47 pm MDT (02:47 UTC) |
Based on data from the 11th at 18:00 UTC; valid on the 12th at 00:00 UTC for use 20:00 to 03:00 UTC; temperatures above 24,000 ft are below zero. Heights are above sea level; a height is left out when the forecast has no wind for it over most of the line (the ground is higher). Ground speed is the airspeed less the headwind; the time en route is for the straight line and ignores climb, descent and routing around weather.
The forecast points as issued
| Point | From | 3,000 | 6,000 | 9,000 | 12,000 | 18,000 | 24,000 | 30,000 | 34,000 | 39,000 |
|---|---|---|---|---|---|---|---|---|---|---|
| DLN | used from 0 nm out; 79 nm from the line | 080/10 -3° | 180/8 -3° | 180/23 -14° | 200/58 -22° | 200/80 -36° | 220/85 -41° | 230/81 -45° | ||
| GTF | used from 47 nm out; 33 nm from the line | 070/21 | 080/18 -6° | 120/5 -5° | 180/30 -14° | 200/53 -24° | 210/80 -38° | 220/83 -44° | 230/68 -46° |
The weather now: both ends and the airports along the way public airports with a weather report within 25 nm of the line, one for each stretch
| Airport | Where | Conditions | Wind | Visibility | Ceiling | Elevation | Reported |
|---|---|---|---|---|---|---|---|
| BZN Bozeman, MT | departure | IFR Sky: a few clouds at 600 feet, overcast at 1,500 feet Weather: light snow, mist | calm | 1.25 mi | 1,500 ft | 4,473 ft | 8:03 pm MDT (02:03 UTC) |
| GTF Great Falls, MT | destination | low IFR Sky: overcast at 500 feet Weather: light snow, mist | from the north (010°) at 11 knots | 0.75 mi | 500 ft | 3,680 ft | 8:06 pm MDT (02:06 UTC) |
The highest airport on this list sits at 4,473 ft; the ground between airports is higher still. Check the sectional chart for the terrain and the minimum safe heights along the line.
At GTF when you get there the forecast at the estimated arrival, 8:42 pm MDT (02:42 UTC)
Wind from the north-northeast at 12 knots, visibility ¾ mile, light snow, mist, a broken layer at 500 feet, overcast at 1,200 feet low IFR
The whole forecast for GTF
- From Sun 6:00 pm MDT (00:00 UTC): wind from the north-northeast at 12 knots, visibility ¾ mile, light snow, mist, a broken layer at 500 feet, overcast at 1,200 feet
- At times between Mon 12:00 am MDT (06:00 UTC) and 3:00 am MDT (09:00 UTC): visibility 2 miles, light snow, overcast at 600 feet
- From Mon 3:00 am MDT (09:00 UTC): wind from the north at 9 knots, visibility 3 miles, light snow, mist, overcast at 500 feet
- From Mon 9:00 am MDT (15:00 UTC): wind light and variable, visibility 6 miles, light snow, mist, a broken layer at 800 feet, overcast at 1,500 feet
- From Mon 3:00 pm MDT (21:00 UTC): wind light and variable, visibility more than 6 miles, a broken layer at 2,500 feet
The forecast for BZN, the departure
- From Sun 6:00 pm MDT (00:00 UTC): wind light and variable, visibility ½ mile, snow, fog, overcast at 300 feet
- At times between Sun 9:00 pm MDT (03:00 UTC) and 12:00 am MDT (06:00 UTC): visibility 2 miles, light snow, mist, scattered clouds at 300 feet, overcast at 1,200 feet
- From Mon 12:00 am MDT (06:00 UTC): wind from the west at 7 knots, visibility 2 miles, light snow, mist, overcast at 800 feet
- At times between Mon 12:00 am MDT (06:00 UTC) and 3:00 am MDT (09:00 UTC): visibility 6 miles, light snow, mist, overcast at 800 feet
- From Mon 3:00 am MDT (09:00 UTC): wind light and variable, visibility more than 6 miles, overcast at 800 feet
- From Mon 12:00 pm MDT (18:00 UTC): wind light and variable, visibility more than 6 miles, scattered clouds at 800 feet, overcast at 2,000 feet
- From Mon 5:00 pm MDT (23:00 UTC): wind light and variable, visibility more than 6 miles, scattered clouds at 1,500 feet, a broken layer at 11,000 feet
Temporary flight restrictions on the line or within 25 nm of it
No temporary flight restriction on or near this route right now.
Daylight
Sunset at BZN 6:44 pm MDT (00:44 UTC), at GTF 6:43 pm MDT (00:43 UTC) (civil twilight ends 7:14 pm MDT (01:14 UTC)). At 120 knots the arrival at GTF is after sunset there (6:45 pm MDT (00:45 UTC)).
Each restriction opens the FAA's own page with the exact area, heights and times. Ordinary notices to air missions (closed runways, lights out) are not shown: the FAA's notice search is not open to sites like this one at this time.
Radar and forecast charts for the regions crossed government pictures, the latest each time the page loads
Sources: the Aviation Weather Center's data service (SIGMETs, AIRMETs, graphical AIRMETs, pilot reports, winds and temperatures aloft, observations and terminal forecasts), the National Weather Service radar, the Weather Prediction Center's charts, the FAA's temporary flight restriction list and shapes, and the FAA's airport file for the positions, elevations and magnetic variation. Fetched when the page is viewed and kept a few minutes. Each leg is the straight line between its two airports; airways, terrain and airspace are not considered. The airports in detail: Bozeman Yellowstone International, Great Falls International.