City Of Colorado Springs Municipal to Helena Regional COS → HLN
567 nautical miles (653 statute miles) northwest on a straight line, true course 328°, about 320° magnetic at the departure end (variation 8E). At 120 knots that is 4 h 07 min at the quickest height in today's winds (30,000 ft, a 18-knot tailwind), arriving about 4:56 am MDT (10:56 UTC), after sunset at the destination. Right now COS is VFR, wind from the south (180°) at 10 knots; HLN is VFR, wind from the west (270°) at 8 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: 1 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 C10C: thunderstorms (a convective SIGMET) up to 34,000 ft, moving from the southwest at 40 knots, until 1:55 am MDT (07:55 UTC). Near the route, at the departure end.
as issued
WSUS32 KKCI 120555 MKCC WST 120555 CONVECTIVE SIGMET 10C VALID UNTIL 0755Z CO NM FROM 20NNE PUB-40WSW LAA-30WSW CIM-50WSW ALS-50ESE HBU-20NNE PUB AREA TS MOV FROM 22040KT. TOPS TO FL340.
- 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 first 338 nm of the route.
- AIRMET TANGO 4W: moderate turbulence above 18,000 ft from 18,000 ft to 38,000 ft. Over the first 358 nm of the route.
- AIRMET TANGO 4W: moderate turbulence below 18,000 ft up to 18,000 ft. Over the first 378 nm of the route.
- AIRMET SIERRA 1E: mountains obscured by cloud (due to mountains obscured by clouds, precipitation, mist). Over the last 408 nm of the route.
- AIRMET ZULU 2C: moderate icing up to 23,000 ft. Over the route from 189 to 438 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 199 to 289 nm out.
- 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 last 249 nm of the route.
- AIRMET ZULU 2C: moderate icing up to 23,000 ft. Over the last 110 nm of the route.
- AIRMET TANGO 1W: moderate turbulence above 18,000 ft from 18,000 ft to 36,000 ft. Over the last 50 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 COS.
Pilot reports along the route within 50 nm of the line, last three hours, the serious ones first
- A321 at 31,000 ft, 8 nm east, 12:41 am MDT (06:41 UTC): moderate turbulence, remarks: mtw +/-15KT zdvwc. At the departure end, 8 nm east of the line.
as filed, and in English
COS UA /OV BRK/TM 0641/FL310/TP A321/TB MOD/RM MTW +/-15KT. ZDVWC-
- Report
- a routine report filed through COS
- Where
- over BRK
- Time
- 06:41 UTC
- Height
- at 31,000 ft
- Aircraft
- A321
- Turbulence
- moderate
- Remarks
- mtw +/-15KT zdvwc
- B38M at 30,000 ft, 22 nm northeast, 11:45 pm MDT (05:45 UTC): moderate chop turbulence. 239 nm along the route, 22 nm northeast of the line.
as filed, and in English
RIW UA /OV BOY126080/TM 0545/FL300/TP B38M/TB CONS MOD CHOP /ZLC
- Report
- a routine report filed through RIW
- Where
- 80 nm southeast (126°) of BOY
- Time
- 05:45 UTC
- Height
- at 30,000 ft
- Aircraft
- B38M
- Turbulence
- continuous moderate chop zlc
- CRJ2 at 22,000 ft, 25 nm southwest, 12:35 am MDT (06:35 UTC): no turbulence up to 26,000 ft, no icing, clear from 22,000 ft to 60,000 ft, remarks: during the descent ZDVWC-26. 40 nm along the route, 25 nm southwest of the line.
as filed, and in English
DEN UA /OV DEN220060/TM 0635/FL220/TP CRJ2/SK SKC/TB NEG BLO 260/IC NEG/RM DURD/ ZDVWC-26
- Report
- a routine report filed through DEN
- Where
- 60 nm southwest (220°) of DEN
- Time
- 06:35 UTC
- Height
- at 22,000 ft
- Aircraft
- CRJ2
- Sky
- clear
- Turbulence
- no below 26,000 ft
- Icing
- none
- Remarks
- during the descent ZDVWC-26
- E170 at 22,500 ft, 22 nm southwest, 11:06 pm MDT (05:06 UTC): light to moderate turbulence up to 23,000 ft, remarks: during the descent tbarr star ZDVWC-13. 40 nm along the route, 22 nm southwest of the line.
as filed, and in English
DEN UA /OV DEN216057/TM 0506/FL225/TP E170/TB CONS LGT OCNL MOD BLO 230/RM DURD TBARR STAR. ZDVWC-13
- Report
- a routine report filed through DEN
- Where
- 57 nm southwest (216°) of DEN
- Time
- 05:06 UTC
- Height
- at 22,500 ft
- Aircraft
- E170
- Turbulence
- continuous light occasional moderate below 23,000 ft
- Remarks
- during the descent tbarr star ZDVWC-13
- B738 at 23,000 ft, 26 nm southwest, 12:23 am MDT (06:23 UTC): no turbulence from 23,000 ft to 26,000 ft, clear from 23,000 ft to 60,000 ft, remarks: during the descent sskii star ZDVWC-06. 50 nm along the route, 26 nm southwest of the line.
as filed, and in English
DEN UA /OV DEN230060/TM 0623/FL230/TP B738/SK SKC/TB NEG 230-260/RM DURD SSKII STAR. ZDVWC-06
- Report
- a routine report filed through DEN
- Where
- 60 nm southwest (230°) of DEN
- Time
- 06:23 UTC
- Height
- at 23,000 ft
- Aircraft
- B738
- Sky
- clear
- Turbulence
- no from 23,000 ft to 26,000 ft
- Remarks
- during the descent sskii star ZDVWC-06
- B738 descending, 34 nm northeast, 12:15 am MDT (06:15 UTC): light chop turbulence. 50 nm along the route, 34 nm northeast of the line.
as filed, and in English
DEN UA /OV DEN/TM 0615/FLDURD/TP B738/TB LGT CHOP
- Report
- a routine report filed through DEN
- Where
- over DEN
- Time
- 06:15 UTC
- Height
- during the descent
- Aircraft
- B738
- Turbulence
- light chop
- A20N at 25,000 ft, 10 nm southwest, 12:19 am MDT (06:19 UTC): light chop turbulence up to 26,000 ft, remarks: during the climb ZDVWC-06. 70 nm along the route, 10 nm southwest of the line.
as filed, and in English
DEN UA /OV DEN250045/TM 0619/FL250/TP A20N/TB OCNL LGT CHOP BLO 260/RM DURC. ZDVWC-06
- Report
- a routine report filed through DEN
- Where
- 45 nm west (250°) of DEN
- Time
- 06:19 UTC
- Height
- at 25,000 ft
- Aircraft
- A20N
- Turbulence
- occasional light chop below 26,000 ft
- Remarks
- during the climb ZDVWC-06
- B38M at 21,500 ft, 17 nm northeast, 10:33 pm MDT (04:33 UTC): light turbulence up to 25,000 ft, remarks: during the descent flati star ZDVWC-13. 110 nm along the route, 17 nm northeast of the line.
as filed, and in English
DEN UA /OV DEN305065/TM 0433/FL215/TP B38M/TB LGT BLO 250/RM DURD FLATI STAR. ZDVWC-13
- Report
- a routine report filed through DEN
- Where
- 65 nm northwest (305°) of DEN
- Time
- 04:33 UTC
- Height
- at 21,500 ft
- Aircraft
- B38M
- Turbulence
- light below 25,000 ft
- Remarks
- during the descent flati star ZDVWC-13
- E73L descending, 2 nm southwest, 12:20 am MDT (06:20 UTC): remarks: breaking action good broke out about 600FT above ground. 508 nm along the route, 2 nm southwest of the line.
as filed, and in English
BZN UA /OV BZN/TM 0620/FLDURD/TP E73L/RM BREAKING ACTION GOOD. BROKE OUT ABOUT 600FT AGL
- Report
- a routine report filed through BZN
- Where
- over BZN
- Time
- 06:20 UTC
- Height
- during the descent
- Aircraft
- E73L
- Remarks
- breaking action good broke out about 600FT above ground
- B737 , 2 nm southwest, 11:31 pm MDT (05:31 UTC): remarks: saw the light at 500FT braking good no icing. 508 nm along the route, 2 nm southwest of the line.
as filed, and in English
BZN UA /OV BZN/TM 0531/FLBURD/TP B737/RM SAW THE LIGHT AT 500FT. BRAKING GOOD. NEG ICING
- Report
- a routine report filed through BZN
- Where
- over BZN
- Time
- 05:31 UTC
- Height
- at BURD
- Aircraft
- B737
- Remarks
- saw the light at 500FT braking good no icing
Winds aloft along the route, and the time en route the forecast for use 02:00–09:00 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 6 forecast points nearest it (DEN, RKS, LND, BIL, 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 |
|---|---|---|---|---|---|---|
| 8,500 ft | 210° at 17 kt | −9 kt | 6 °C | 129 kt | 4 h 24 min | 5:13 am MDT (11:13 UTC) |
| 10,500 ft | 220° at 25 kt | −6 kt | 3 °C | 126 kt | 4 h 30 min | 5:19 am MDT (11:19 UTC) |
| 12,500 ft | 230° at 34 kt | −4 kt | 0 °C | 124 kt | 4 h 34 min | 5:23 am MDT (11:23 UTC) |
| 14,500 ft | 220° at 36 kt | −7 kt | -4 °C | 127 kt | 4 h 28 min | 5:17 am MDT (11:17 UTC) |
| 16,500 ft | 220° at 38 kt | −10 kt | -8 °C | 130 kt | 4 h 22 min | 5:11 am MDT (11:11 UTC) |
| 18,000 ft FL180 | 220° at 40 kt | −13 kt | -11 °C | 133 kt | 4 h 16 min | 5:05 am MDT (11:05 UTC) |
| 24,000 ft FL240 | 220° at 47 kt | −14 kt | -23 °C | 134 kt | 4 h 14 min | 5:03 am MDT (11:03 UTC) |
| 30,000 ft FL300 | 220° at 55 kt | −18 kt | -30 °C | 138 kt | 4 h 07 min | 4:56 am MDT (10:56 UTC) |
| 34,000 ft FL340 | 220° at 65 kt | −14 kt | -36 °C | 134 kt | 4 h 14 min | 5:03 am MDT (11:03 UTC) |
| 39,000 ft FL390 | 230° at 64 kt | −7 kt | -44 °C | 127 kt | 4 h 28 min | 5:17 am MDT (11:17 UTC) |
Based on data from the 12th at 00:00 UTC; valid on the 12th at 06:00 UTC for use 02:00 to 09:00 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 |
|---|---|---|---|---|---|---|---|---|---|---|
| DEN | used from 0 nm out; 45 nm from the line | 240/21 14° | 250/44 6° | 220/49 -8° | 220/49 -21° | 230/54 -30° | 240/57 -35° | 240/49 -45° | ||
| RKS | used from 149 nm out; 106 nm from the line | 200/41 | 220/44 1° | 220/35 -11° | 220/46 -24° | 210/53 -27° | 220/62 -35° | 230/61 -44° | ||
| LND | used from 249 nm out; 35 nm from the line | 200/23 6° | 220/31 1° | 220/39 -11° | 230/39 -23° | 220/51 -28° | 220/66 -37° | 230/68 -45° | ||
| BIL | used from 398 nm out; 91 nm from the line | 080/13 | 180/9 -2° | 210/38 0° | 220/51 -11° | 210/46 -22° | 210/58 -35° | 230/73 -39° | 230/72 -45° | |
| DLN | used from 448 nm out; 81 nm from the line | 090/6 -6° | 240/22 -4° | 210/34 -16° | 210/62 -25° | 210/66 -34° | 210/82 -36° | 220/77 -42° | ||
| GTF | used from 548 nm out; 64 nm from the line | 070/11 | 080/15 -7° | 110/19 -9° | 190/25 -14° | 200/34 -23° | 200/54 -39° | 220/66 -40° | 220/77 -44° |
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 |
|---|---|---|---|---|---|---|---|
| COS Colorado Springs, CO | departure | VFR Sky: a few clouds at 2,000 feet, a few clouds at 18,000 feet | from the south (180°) at 10 knots | 10+ mi | none | 6,187 ft | 11:54 pm MDT (05:54 UTC) |
| APA Denver, CO | 40 nm out, 19 nm northeast of the line, tower | VFR Sky: a few clouds at 12,000 feet, scattered clouds at 22,000 feet | from the south (170°) at 9 knots | 10+ mi | none | 5,884 ft | 05:53 UTC |
| BJC Denver, CO | 70 nm out, 19 nm northeast of the line, tower | VFR | from the south-southeast (150°) at 7 knots | 10+ mi | none | 5,673 ft | 06:35 UTC |
| SAA Saratoga, WY | 189 nm out, 5 nm east of the line | reported, no category | from the south-southeast (160°) at 22 knots, gusting to 34 | 10+ mi | none | 7,014 ft | 06:30 UTC |
| RIW Riverton, WY | 309 nm out, 3 nm southwest of the line | VFR | from the north-northwest (340°) at 8 knots | 10+ mi | none | 5,516 ft | 05:53 UTC |
| BZN Bozeman, MT | 508 nm out, 2 nm southwest of the line, tower | marginal VFR Sky: scattered clouds at 500 feet, a broken layer at 2,800 feet, overcast at 3,700 feet Weather: light snow, mist | from the west-southwest (240°) at 3 knots | 4 mi | 2,800 ft | 4,473 ft | 06:45 UTC |
| HLN Helena, MT | destination | VFR Sky: a few clouds at 2,100 feet, overcast at 5,000 feet | from the west (270°) at 8 knots | 10+ mi | 5,000 ft | 3,877 ft | 11:53 pm MDT (05:53 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 HLN when you get there the forecast at the estimated arrival, 4:56 am MDT (10:56 UTC)
Wind light and variable, visibility more than 6 miles, overcast at 1,500 feet marginal VFR
30% chance between Mon 3:00 am MDT (09:00 UTC) and 6:00 am MDT (12:00 UTC): visibility 3 miles, light snow, overcast at 1,000 feet marginal VFR
The whole forecast for HLN
- From Mon 12:00 am MDT (06:00 UTC): wind from the west-northwest at 14 knots, visibility 3 miles, light snow, overcast at 3,500 feet
- At times between Mon 12:00 am MDT (06:00 UTC) and 3:00 am MDT (09:00 UTC): visibility 1 mile, light snow, overcast at 1,500 feet
- From Mon 3:00 am MDT (09:00 UTC): wind light and variable, visibility more than 6 miles, overcast at 1,500 feet
- 30% chance between Mon 3:00 am MDT (09:00 UTC) and 6:00 am MDT (12:00 UTC): visibility 3 miles, light snow, overcast at 1,000 feet
- From Mon 3:00 pm MDT (21:00 UTC): wind light and variable, visibility more than 6 miles, scattered clouds at 1,500 feet, scattered clouds at 3,500 feet
The forecast for COS, the departure
- From Mon 12:00 am MDT (06:00 UTC): wind from the south at 12 knots, visibility more than 6 miles, scattered clouds at 6,000 feet, a broken layer at 20,000 feet
- From Mon 6:00 am MDT (12:00 UTC): wind from the north-northeast at 8 knots, visibility more than 6 miles, clear skies
- 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
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 21 nm from the route, 30 nm along the route · a hazard on the ground (fire-fighting, a chemical spill, rescue work) · until 13 October · ZDV
Daylight
Sunset at COS 6:23 pm MDT (00:23 UTC), at HLN 6:45 pm MDT (00:45 UTC) (civil twilight ends 7:15 pm MDT (01:15 UTC)). At 120 knots the arrival at HLN is before sunrise there (7:41 am MDT (13:41 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: City Of Colorado Springs Municipal, Helena Regional.