Billings Logan International to Boise Air Trml/Gowen Field BIL → BOI
354 nautical miles (408 statute miles) west on a straight line, true course 250°, about 240° magnetic at the departure end (variation 10E). At 120 knots that is 2 h 43 min at the quickest height in today's winds (4,500 ft, a 10-knot tailwind), arriving about 9:14 pm MDT (03:14 UTC), after sunset at the destination. Right now BIL is IFR, wind from the north (010°) at 14 knots; BOI is VFR, wind calm. 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: 51 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
- SIGMET W70W: thunderstorms (a convective SIGMET) up to 32,000 ft, moving from the southwest at 40 knots, until 7:55 pm MDT (01:55 UTC). Near the route, at the departure end.
as issued
WSUS33 KKCI 112355 MKCW WST 112355 CONVECTIVE SIGMET 70W VALID UNTIL 0155Z MT WY FROM 30SSW MLS-60WNW BFF-40SSE OCS-10S BPI-10S BIL-30SSW MLS AREA TS MOV FROM 22040KT. TOPS TO FL320.
- 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 first 295 nm of the route.
- AIRMET TANGO 4W: moderate turbulence above 18,000 ft from 18,000 ft to 36,000 ft. Over the whole route.
- AIRMET SIERRA 1E: mountains obscured by cloud (due to mountains obscured by clouds, precipitation, mist). Over the first 335 nm of the route.
- AIRMET TANGO 4W: moderate turbulence below 18,000 ft up to 18,000 ft. Over the route from 10 to 128 nm out.
- AIRMET TANGO 1W: low-level wind shear (due to air speed loss or gain of 20 knots or more below 2,000 ft above the ground). Over the route from 98 to 98 nm out.
- AIRMET ZULU 3C: moderate icing up to 22,000 ft. Over the last 138 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 BIL.
Pilot reports along the route within 50 nm of the line, last three hours, the serious ones first
- B738 at 33,000 ft, 22 nm south, 5:57 pm MDT (23:57 UTC): moderate chop turbulence from 31,000 ft to 33,000 ft. 157 nm along the route, 22 nm south of the line.
as filed, and in English
IDA UA /OV DBS015030/TM 2357/FL330/TP B738/TB MOD CHOP 310-330 /ZLC
- Report
- a routine report filed through IDA
- Where
- 30 nm north (015°) of DBS
- Time
- 23:57 UTC
- Height
- at 33,000 ft
- Aircraft
- B738
- Turbulence
- moderate chop from 31,000 ft to 33,000 ft zlc
- B737 descending, 37 nm northwest, 6:28 pm MDT (00:28 UTC): scattered clouds above 8,000 ft, fog, snow, remarks: broke out about 100FT above mins. 98 nm along the route, 37 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
- E550 at 21,000 ft, 38 nm south, 5:27 pm MDT (23:27 UTC): light turbulence, a few clouds above 7,000 ft, remarks: during the climb zlc. 276 nm along the route, 38 nm south of the line.
as filed, and in English
SUN UA /OV SUN/TM 2327/FL210/TP E550/SK FEW070/TB CONS LGT/RM DURC /ZLC
- Report
- a routine report filed through SUN
- Where
- over SUN
- Time
- 23:27 UTC
- Height
- at 21,000 ft
- Aircraft
- E550
- Sky
- a few clouds from 7,000 ft
- Turbulence
- continuous light
- Remarks
- during the climb zlc
- CL60 descending, 2 nm southeast, 5:00 pm MDT (23:00 UTC): remarks: + 10 knots on final. At the destination end, 2 nm southeast of the line.
as filed, and in English
BOI UA /OV BOI/TM 2300/FLDURD/TP CL60/RM +/- 10 KTS ON FINAL
- Report
- a routine report filed through BOI
- Where
- over BOI
- Time
- 23:00 UTC
- Height
- during the descent
- Aircraft
- CL60
- Remarks
- + 10 knots on final
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 3 forecast points nearest it (BIL, DLN, BOI). 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 | 040° at 11 kt | −10 kt | 4 °C | 130 kt | 2 h 43 min | 9:14 pm MDT (03:14 UTC) |
| 6,500 ft | 050° at 9 kt | −9 kt | 3 °C | 129 kt | 2 h 45 min | 9:16 pm MDT (03:16 UTC) |
| 8,500 ft | 100° at 6 kt | −5 kt | -2 °C | 125 kt | 2 h 50 min | 9:21 pm MDT (03:21 UTC) |
| 10,500 ft | 170° at 10 kt | +3 kt | -2 °C | 117 kt | 3 h 02 min | 9:33 pm MDT (03:33 UTC) |
| 12,500 ft | 190° at 19 kt | +11 kt | -4 °C | 109 kt | 3 h 15 min | 9:46 pm MDT (03:46 UTC) |
| 14,500 ft | 200° at 24 kt | +15 kt | -8 °C | 105 kt | 3 h 22 min | 9:53 pm MDT (03:53 UTC) |
| 16,500 ft | 200° at 28 kt | +19 kt | -12 °C | 101 kt | 3 h 30 min | 10:01 pm MDT (04:01 UTC) |
| 18,000 ft FL180 | 200° at 32 kt | +22 kt | -15 °C | 98 kt | 3 h 37 min | 10:08 pm MDT (04:08 UTC) |
| 24,000 ft FL240 | 210° at 58 kt | +43 kt | -23 °C | 77 kt | 4 h 36 min | 11:07 pm MDT (05:07 UTC) |
| 30,000 ft FL300 | 200° at 69 kt | +46 kt | -35 °C | 74 kt | 4 h 47 min | 11:18 pm MDT (05:18 UTC) |
| 34,000 ft FL340 | 220° at 78 kt | +67 kt | -40 °C | 53 kt | 6 h 41 min | 1:12 am MDT (07:12 UTC) |
| 39,000 ft FL390 | 230° at 75 kt | +72 kt | -45 °C | 48 kt | 7 h 22 min | 1:53 am MDT (07:53 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 |
|---|---|---|---|---|---|---|---|---|---|---|
| BIL | used from 0 nm out; 25 nm from the line | 080/24 | 130/14 -1° | 180/33 0° | 210/43 -10° | 220/58 -21° | 200/55 -36° | 220/75 -44° | 240/83 -48° | |
| DLN | used from 98 nm out; 55 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° | ||
| BOI | used from 246 nm out; 84 nm from the line | 330/14 4° | 230/5 -2° | 220/20 -7° | 210/37 -20° | 200/59 -26° | 200/67 -34° | 210/73 -35° | 220/62 -41° |
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 |
|---|---|---|---|---|---|---|---|
| BIL Billings, MT | departure | IFR Sky: a broken layer at 800 feet, overcast at 1,200 feet Weather: light rain, mist | from the north (010°) at 14 knots | 6 mi | 800 ft | 3,662 ft | 5:53 pm MDT (23:53 UTC) |
| LVM Livingston, MT | 79 nm out, 22 nm north of the line | low IFR Sky: overcast at 400 feet Weather: light snow, mist | from the east (080°) at 14 knots | 0.75 mi | 400 ft | 4,659 ft | 00:23 UTC |
| WYS West Yellowstone, MT | 128 nm out, 25 nm southeast of the line | IFR Sky: scattered clouds at 300 feet, a broken layer at 900 feet, overcast at 2,000 feet Weather: light rain, mist | from the north (010°) at 5 knots | 4 mi | 900 ft | 6,649 ft | 00:10 UTC |
| EKS Ennis, MT | 138 nm out, 17 nm north of the line | IFR Sky: scattered clouds at 300 feet, scattered clouds at 700 feet, a broken layer at 2,100 feet Weather: light snow, mist | from the north (350°) at 11 knots | 1 mi | 2,100 ft | 5,432 ft | 00:15 UTC |
| LLJ Challis, ID | 256 nm out, 17 nm north of the line | marginal VFR Sky: a broken layer at 2,800 feet, overcast at 3,500 feet Weather: light rain | from the north-northwest (340°) at 10 knots | 10+ mi | 2,800 ft | 5,075 ft | 00:09 UTC |
| BOI Boise, ID | destination | VFR Sky: overcast at 4,200 feet Weather: light rain | calm | 10+ mi | 4,200 ft | 2,871 ft | 5:53 pm MDT (23:53 UTC) |
The highest airport on this list sits at 6,649 ft; the ground between airports is higher still. Check the sectional chart for the terrain and the minimum safe heights along the line.
At BOI when you get there the forecast at the estimated arrival, 9:14 pm MDT (03:14 UTC)
Wind from the northwest at 11 knots, visibility more than 6 miles, showers nearby, scattered clouds at 5,000 feet, overcast at 7,000 feet VFR
At times between Sun 6:00 pm MDT (00:00 UTC) and 10:00 pm MDT (04:00 UTC): light rain showers, overcast at 5,000 feet VFR
The whole forecast for BOI
- From Sun 6:00 pm MDT (00:00 UTC): wind from the northwest at 11 knots, visibility more than 6 miles, showers nearby, scattered clouds at 5,000 feet, overcast at 7,000 feet
- At times between Sun 6:00 pm MDT (00:00 UTC) and 10:00 pm MDT (04:00 UTC): light rain showers, overcast at 5,000 feet
- From Mon 12:00 am MDT (06:00 UTC): wind from the west-northwest at 5 knots, visibility more than 6 miles, a few clouds at 5,000 feet, a broken layer at 8,000 feet
- From Mon 12:00 pm MDT (18:00 UTC): wind from the northwest at 10 knots, visibility more than 6 miles, a broken layer at 10,000 feet
The forecast for BIL, the departure
- From Sun 6:00 pm MDT (00:00 UTC): wind from the north-northeast at 11 knots, visibility 6 miles, light rain snow, mist, overcast at 500 feet
- From Sun 9:00 pm MDT (03:00 UTC): wind from the north at 8 knots, visibility 2 miles, light snow, mist, freezing fog, a broken layer at 500 feet
- From Mon 8:00 am MDT (14:00 UTC): wind from the north-northwest at 5 knots, visibility 6 miles, mist, showers nearby, scattered clouds at 300 feet, a broken layer at 700 feet and more above
- From Mon 3:00 pm MDT (21:00 UTC): wind from the northeast at 6 knots, visibility 6 miles, mist, overcast at 1,500 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 BIL 6:33 pm MDT (00:33 UTC), at BOI 7:06 pm MDT (01:06 UTC) (civil twilight ends 7:35 pm MDT (01:35 UTC)). At 120 knots the arrival at BOI is after sunset there (7:08 pm MDT (01:08 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: Billings Logan International, Boise Air Trml/Gowen Field.