Great Falls International to City Of Colorado Springs Municipal GTF → COS
597 nautical miles (687 statute miles) southeast on a straight line, true course 148°, about 135° magnetic at the departure end (variation 13E). At 120 knots that is 4 h 47 min at the quickest height in today's winds (7,500 ft, a 5-knot tailwind), arriving about 10:51 am MDT (16:51 UTC). Right now GTF is low IFR, wind from the north-northwest (330°) at 6 knots; COS is VFR, wind from the south (190°) at 13 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: 5 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 first 269 nm of the route.
- AIRMET ZULU 2C: moderate icing up to 18,000 ft. Over the first 139 nm of the route.
- AIRMET SIERRA 1E: mountains obscured by cloud (due to mountains obscured by clouds, precipitation, mist). Over the route from 10 to 477 nm out.
- AIRMET ZULU 2C: moderate icing up to 23,000 ft. Over the route from 149 to 328 nm out.
- AIRMET TANGO 4W: moderate turbulence above 18,000 ft (due to mountain wave) from 34,000 ft to 43,000 ft. Over the last 259 nm of the route.
- 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 348 to 467 nm out.
- AIRMET TANGO 5W: strong surface winds (30 knots or more) (due to sustained surface winds greater than 30 knots). Over the route from 348 to 408 nm out.
- AIRMET TANGO 2W: moderate turbulence below 18,000 ft (due to mountain wave) up to 22,000 ft. Over the last 229 nm of the route.
- 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 last 20 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 GTF.
Pilot reports along the route within 50 nm of the line, last three hours, the serious ones first
- BE9L at 17,000 ft, 32 nm northeast, 3:42 am MDT (09:42 UTC): light rime icing from 15,000 ft to 17,000 ft, 0 °C, remarks: zdvwc. 328 nm along the route, 32 nm northeast of the line.
as filed, and in English
CPR UA /OV DDY250025/TM 0942/FL170/TP BE9L/TA 00/IC LGT RIME 150-170/RM ZDVWC
- Report
- a routine report filed through CPR
- Where
- 25 nm west (250°) of DDY
- Time
- 09:42 UTC
- Height
- at 17,000 ft
- Aircraft
- BE9L
- Temperature
- 0 °C
- Icing
- light rime from 15,000 ft to 17,000 ft
- Remarks
- zdvwc
- CRJ2 at 19,000 ft, 4 nm north, 5:49 am MDT (11:49 UTC): no turbulence, remarks: ZDVWC-13. 477 nm along the route, 4 nm north of the line.
as filed, and in English
DEN UA /OV DEN304074/TM 1149/FL190/TP CRJ2/TB NEG/RM ZDVWC-13
- Report
- a routine report filed through DEN
- Where
- 74 nm northwest (304°) of DEN
- Time
- 11:49 UTC
- Height
- at 19,000 ft
- Aircraft
- CRJ2
- Turbulence
- none
- Remarks
- ZDVWC-13
- CRJ2 at 24,000 ft, 18 nm northeast, 5:45 am MDT (11:45 UTC): no turbulence, remarks: ZDVWC-13. 487 nm along the route, 18 nm northeast of the line.
as filed, and in English
DEN UA /OV DEN314057/TM 1145/FL240/TP CRJ2/TB NEG/RM ZDVWC-13
- Report
- a routine report filed through DEN
- Where
- 57 nm northwest (314°) of DEN
- Time
- 11:45 UTC
- Height
- at 24,000 ft
- Aircraft
- CRJ2
- Turbulence
- none
- Remarks
- ZDVWC-13
- B38M at 21,000 ft, 1 nm southeast, 5:24 am MDT (11:24 UTC): light to moderate chop turbulence, remarks: during the climb zdvwc. 517 nm along the route, 1 nm southeast of the line.
as filed, and in English
DEN UA /OV DEN277039/TM 1124/FL210/TP B38M/TB LGT-MOD CHOP BLO 180 NEG ABV 180/RM DURC. ZDVWC
- Report
- a routine report filed through DEN
- Where
- 39 nm west (277°) of DEN
- Time
- 11:24 UTC
- Height
- at 21,000 ft
- Aircraft
- B38M
- Turbulence
- light to moderate chop below 18,000 ft no above 18,000 ft
- Remarks
- during the climb zdvwc
- B763 at 23,000 ft, 3 nm east, 4:26 am MDT (10:26 UTC): light chop turbulence, remarks: zdvwc. 517 nm along the route, 3 nm east of the line.
as filed, and in English
DEN UA /OV DEN278037/TM 1026/FL230/TP B763/TB OCNL LGT CHOP/RM ZDVWC
- Report
- a routine report filed through DEN
- Where
- 37 nm west (278°) of DEN
- Time
- 10:26 UTC
- Height
- at 23,000 ft
- Aircraft
- B763
- Turbulence
- occasional light chop
- Remarks
- zdvwc
- UAL1735 at 19,000 ft, 13 nm southwest, 5:50 am MDT (11:50 UTC): light chop turbulence, wind 237° at 58 knots. 547 nm along the route, 13 nm southwest of the line.
as filed, and in English
ARP UAL1735 3925N 10525W 1150 F190 237/058KT TB INTMT LGT CHOP IC
- Report
- a routine report filed through ARP
- B752 at 23,000 ft, 29 nm southwest, 5:39 am MDT (11:39 UTC): no turbulence, remarks: zdvwc. 547 nm along the route, 29 nm southwest of the line.
as filed, and in English
DEN UA /OV DEN231058/TM 1139/FL230/TP B752/TB NEG/RM ZDVWC
- Report
- a routine report filed through DEN
- Where
- 58 nm southwest (231°) of DEN
- Time
- 11:39 UTC
- Height
- at 23,000 ft
- Aircraft
- B752
- Turbulence
- none
- Remarks
- zdvwc
- B738 at 11,000 ft, 6 nm southeast, 5:42 am MDT (11:42 UTC): light chop turbulence, remarks: during the climb. At the destination end, 6 nm southeast of the line.
as filed, and in English
COS UA /OV BRK172014/TM 1142/FL110/TP B738/TB LGT CHOP/RM DURC
- Report
- a routine report filed through COS
- Where
- 14 nm south (172°) of BRK
- Time
- 11:42 UTC
- Height
- at 11,000 ft
- Aircraft
- B738
- Turbulence
- light chop
- Remarks
- during the climb
Winds aloft along the route, and the time en route the forecast for use 08:00–15:00 UTC · at 120 knots true airspeed
The eastbound cruising heights for this course (VFR: odd thousands plus 500 ft; above 18,000 ft the forecast levels), with the wind averaged along the line from the 5 forecast points nearest it (GTF, BIL, LND, RKS, DEN). A plus sign is a headwind, a minus sign a tailwind.
| Height | Average wind | Head- or tailwind | Temperature | Ground speed | Time en route | Arrival |
|---|---|---|---|---|---|---|
| 7,500 ft | 260° at 12 kt | −5 kt | 6 °C | 125 kt | 4 h 47 min | 10:51 am MDT (16:51 UTC) |
| 9,500 ft | 260° at 14 kt | −4 kt | 2 °C | 124 kt | 4 h 49 min | 10:53 am MDT (16:53 UTC) |
| 11,500 ft | 240° at 19 kt | −1 kt | 0 °C | 121 kt | 4 h 56 min | 11:00 am MDT (17:00 UTC) |
| 13,500 ft | 240° at 25 kt | +2 kt | -3 °C | 118 kt | 5 h 04 min | 11:08 am MDT (17:08 UTC) |
| 15,500 ft | 230° at 31 kt | +6 kt | -8 °C | 114 kt | 5 h 14 min | 11:18 am MDT (17:18 UTC) |
| 17,500 ft | 230° at 37 kt | +10 kt | -11 °C | 110 kt | 5 h 26 min | 11:30 am MDT (17:30 UTC) |
| 18,000 ft FL180 | 220° at 39 kt | +11 kt | -12 °C | 109 kt | 5 h 29 min | 11:33 am MDT (17:33 UTC) |
| 24,000 ft FL240 | 230° at 48 kt | +12 kt | -23 °C | 108 kt | 5 h 32 min | 11:36 am MDT (17:36 UTC) |
| 30,000 ft FL300 | 220° at 56 kt | +19 kt | -33 °C | 101 kt | 5 h 55 min | 11:59 am MDT (17:59 UTC) |
| 34,000 ft FL340 | 220° at 63 kt | +18 kt | -37 °C | 102 kt | 5 h 51 min | 11:55 am MDT (17:55 UTC) |
| 39,000 ft FL390 | 230° at 64 kt | +16 kt | -45 °C | 104 kt | 5 h 44 min | 11:48 am MDT (17:48 UTC) |
Based on data from the 12th at 06:00 UTC; valid on the 12th at 12:00 UTC for use 08:00 to 15:00 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 |
|---|---|---|---|---|---|---|---|---|---|---|
| GTF | used from 0 nm out; 25 nm from the line | L/V | L/V -7° | 240/8 -8° | 240/30 -14° | 240/40 -28° | 210/52 -38° | 210/76 -38° | 220/72 -43° | |
| BIL | used from 99 nm out; 54 nm from the line | 300/14 | 270/19 -2° | 260/26 -2° | 220/28 -13° | 210/51 -25° | 220/56 -33° | 220/61 -39° | 220/72 -45° | |
| LND | used from 199 nm out; 88 nm from the line | 240/10 3° | 240/30 0° | 220/42 -13° | 230/52 -23° | 220/54 -33° | 220/52 -36° | 220/53 -44° | ||
| RKS | used from 398 nm out; 118 nm from the line | 250/9 | 230/21 -1° | 210/43 -14° | 220/59 -23° | 220/55 -32° | 220/53 -35° | 220/48 -44° | ||
| DEN | used from 448 nm out; 75 nm from the line | 270/24 11° | 230/13 5° | 230/48 -8° | 230/46 -20° | 230/63 -30° | 240/78 -36° | 240/78 -48° |
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 |
|---|---|---|---|---|---|---|---|
| GTF Great Falls, MT | departure | low IFR Sky: overcast at 400 feet Weather: mist | from the north-northwest (330°) at 6 knots | 0.5 mi | 400 ft | 3,680 ft | 5:53 am MDT (11:53 UTC) |
| HWQ Harlowton, MT | 90 nm out, 22 nm northeast of the line | no report just now | 4,311 ft | ||||
| RED Red Lodge, MT | 159 nm out, 6 nm east of the line | no report just now | 5,762 ft | ||||
| COD Cody, WY | 199 nm out, 8 nm southwest of the line | marginal VFR Sky: overcast at 1,600 feet | from the north-northeast (020°) at 6 knots | 10+ mi | 1,600 ft | 5,102 ft | 11:56 UTC |
| HSG Thermopolis, WY | 259 nm out, 7 nm southwest of the line | marginal VFR Sky: scattered clouds at 1,200 feet, overcast at 2,900 feet | from the north-northeast (020°) at 5 knots | 10+ mi | 2,900 ft | 4,891 ft | 11:55 UTC |
| SAA Saratoga, WY | 408 nm out, 13 nm southwest of the line | reported, no category | calm | 10+ mi | none | 7,014 ft | 11:50 UTC |
| BJC Denver, CO | 527 nm out, 13 nm east of the line, tower | VFR | calm | 10+ mi | none | 5,673 ft | 11:55 UTC |
| APA Denver, CO | 557 nm out, 15 nm northeast of the line, tower | VFR | from the north-northeast (030°) at 12 knots, gusting to 16 | 10+ mi | none | 5,884 ft | 11:53 UTC |
| COS Colorado Springs, CO | destination | VFR | from the south (190°) at 13 knots | 10+ mi | none | 6,187 ft | 5:54 am MDT (11:54 UTC) |
The highest airport on this list sits at 7,014 ft; the ground between airports is higher still. Check the sectional chart for the terrain and the minimum safe heights along the line.
At COS when you get there the forecast at the estimated arrival, 10:51 am MDT (16:51 UTC)
Wind from the southwest at 11 knots, gusting to 22, visibility more than 6 miles, a few clouds at 20,000 feet VFR
The whole forecast for COS
- From Mon 6:00 am MDT (12:00 UTC): wind from the southwest at 11 knots, gusting to 22, visibility more than 6 miles, a few clouds at 20,000 feet
- From Mon 11:00 am MDT (17:00 UTC): wind from the south at 15 knots, gusting to 25, visibility more than 6 miles, scattered clouds at 12,000 feet
- From Mon 1:00 pm MDT (19:00 UTC): wind from the south-southwest at 20 knots, gusting to 30, visibility more than 6 miles, scattered clouds at 12,000 feet
- From Mon 7:00 pm MDT (01:00 UTC): wind from the south-southwest at 12 knots, visibility more than 6 miles, clear skies
- From Mon 10:00 pm MDT (04:00 UTC): wind from the south-southeast at 6 knots, visibility more than 6 miles, scattered clouds at 25,000 feet
The forecast for GTF, the departure
- From Mon 6:00 am MDT (12:00 UTC): wind light and variable, visibility 6 miles, mist, overcast at 600 feet
- At times between Mon 6:00 am MDT (12:00 UTC) and 9:00 am MDT (15:00 UTC): visibility 2 miles, light snow, mist, overcast at 400 feet
- From Mon 10:00 am MDT (16:00 UTC): wind light and variable, visibility more than 6 miles, a broken layer at 700 feet
- From Mon 10:00 pm MDT (04:00 UTC): wind from the south-southwest at 6 knots, visibility more than 6 miles, scattered clouds at 500 feet
Temporary flight restrictions on the line or within 25 nm of it
- 6/8784 LAKE GEORGE, CO, Sunday, October 11, 2026 through Tuesday, October 13, 2026 UTC 23 nm from the route, at the destination end · a hazard on the ground (fire-fighting, a chemical spill, rescue work) · until 13 October · ZDV
Daylight
Sunset at GTF 6:41 pm MDT (00:41 UTC), at COS 6:23 pm MDT (00:23 UTC) (civil twilight ends 6:50 pm MDT (00:50 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: Great Falls International, City Of Colorado Springs Municipal.