George Bush Intcntl/Houston Airport to Helena Regional IAH → HLN
1,264 nautical miles (1,454 statute miles) northwest on a straight line, true course 327°, about 324° magnetic at the departure end (variation 3E). At 120 knots that is 9 h 10 min at the quickest height in today's winds (4,500 ft, a 18-knot tailwind), arriving about 3:38 am MDT (09:38 UTC), after sunset at the destination. 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 W70W: thunderstorms (a convective SIGMET) up to 32,000 ft, moving from the southwest at 40 knots, until 8:55 pm CDT (01:55 UTC). Over the route from 886 to 1085 nm out.
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 TANGO 4W: moderate turbulence above 18,000 ft from 18,000 ft to 36,000 ft. Over the last 577 nm of the route.
- AIRMET TANGO 4W: moderate turbulence below 18,000 ft up to 18,000 ft. Over the route from 746 to 1174 nm out.
- AIRMET SIERRA 1E: mountains obscured by cloud (due to mountains obscured by clouds, precipitation, mist). Over the last 388 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 896 to 1144 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.
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 IAH.
Pilot reports along the route within 50 nm of the line, last three hours, the serious ones first
Not fetched just now.
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 12 forecast points nearest it (CLL, DAL, SPS, GAG, GCK, GLD, DEN, BFF, 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 |
|---|---|---|---|---|---|---|
| 4,500 ft | 180° at 22 kt | −18 kt | 20 °C | 138 kt | 9 h 10 min | 3:38 am MDT (09:38 UTC) |
| 6,500 ft | 190° at 21 kt | −16 kt | 16 °C | 136 kt | 9 h 18 min | 3:46 am MDT (09:46 UTC) |
| 8,500 ft | 200° at 22 kt | −13 kt | 12 °C | 133 kt | 9 h 30 min | 3:58 am MDT (09:58 UTC) |
| 10,500 ft | 210° at 24 kt | −11 kt | 8 °C | 131 kt | 9 h 39 min | 4:07 am MDT (10:07 UTC) |
| 12,500 ft | 210° at 27 kt | −9 kt | 5 °C | 129 kt | 9 h 48 min | 4:16 am MDT (10:16 UTC) |
| 14,500 ft | 220° at 28 kt | −7 kt | 0 °C | 127 kt | 9 h 57 min | 4:25 am MDT (10:25 UTC) |
| 16,500 ft | 220° at 31 kt | −4 kt | -4 °C | 124 kt | 10 h 12 min | 4:40 am MDT (10:40 UTC) |
| 18,000 ft FL180 | 230° at 32 kt | −2 kt | -7 °C | 122 kt | 10 h 22 min | 4:50 am MDT (10:50 UTC) |
| 24,000 ft FL240 | 220° at 37 kt | −5 kt | -18 °C | 125 kt | 10 h 07 min | 4:35 am MDT (10:35 UTC) |
| 30,000 ft FL300 | 230° at 42 kt | +1 kt | -31 °C | 119 kt | 10 h 37 min | 5:05 am MDT (11:05 UTC) |
| 34,000 ft FL340 | 250° at 51 kt | +12 kt | -39 °C | 108 kt | 11 h 42 min | 6:10 am MDT (12:10 UTC) |
| 39,000 ft FL390 | 250° at 51 kt | +19 kt | -49 °C | 101 kt | 12 h 31 min | 6:59 am MDT (12:59 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 |
|---|---|---|---|---|---|---|---|---|---|---|
| CLL | used from 0 nm out; 42 nm from the line | 160/18 | 190/18 16° | 200/19 12° | 220/14 7° | 260/18 -5° | 250/20 -13° | 290/29 -29° | 290/31 -40° | 300/22 -53° |
| DAL | used from 100 nm out; 69 nm from the line | 180/21 | 190/24 15° | 230/20 12° | 220/23 8° | 240/22 -5° | 230/18 -15° | 280/33 -29° | 280/36 -39° | 300/33 -52° |
| SPS | used from 249 nm out; 15 nm from the line | 180/26 | 200/25 16° | 220/19 13° | 220/20 9° | 230/26 -5° | 230/34 -15° | 260/37 -28° | 270/42 -39° | 280/40 -51° |
| GAG | used from 348 nm out; 72 nm from the line | 190/34 19° | 240/27 14° | 240/26 8° | 240/24 -6° | 240/29 -16° | 250/50 -28° | 250/50 -39° | 260/46 -50° | |
| GCK | used from 498 nm out; 55 nm from the line | 200/35 21° | 220/34 14° | 240/30 8° | 240/27 -6° | 240/31 -17° | 240/53 -30° | 250/55 -39° | 250/60 -50° | |
| GLD | used from 597 nm out; 68 nm from the line | 190/29 | 200/30 15° | 240/23 8° | 250/39 -7° | 230/39 -19° | 230/57 -31° | 240/67 -39° | 250/62 -49° | |
| DEN | used from 697 nm out; 37 nm from the line | 190/31 16° | 210/32 7° | 240/41 -8° | 230/47 -21° | 240/56 -32° | 250/65 -37° | 250/61 -47° | ||
| BFF | used from 846 nm out; 105 nm from the line | 120/24 | 180/31 13° | 210/26 7° | 230/25 -7° | 240/41 -20° | 230/52 -36° | 250/56 -41° | 260/57 -45° | |
| LND | used from 896 nm out; 96 nm from the line | 180/33 10° | 190/50 3° | 210/59 -9° | 200/50 -21° | 190/41 -34° | 230/55 -39° | 240/65 -47° | ||
| BIL | used from 1095 nm out; 74 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 1194 nm out; 73 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 1244 nm out; 63 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 |
|---|---|---|---|---|---|---|---|
| IAH Houston, TX | departure | no report just now | 95 ft | ||||
| CXO Houston, TX | 20 nm out, 9 nm northeast of the line, tower | no report just now | 244 ft | ||||
| FWS Fort Worth, TX | 189 nm out, 5 nm southeast of the line, tower | no report just now | 700 ft | ||||
| SPS Wichita Falls, TX | 289 nm out, 2 nm northeast of the line, tower | no report just now | 1,019 ft | ||||
| PYX Perryton, TX | 468 nm out, 6 nm west of the line | no report just now | 2,918 ft | ||||
| JHN Johnson City, KS | 557 nm out, 1 nm southeast of the line | no report just now | 3,325 ft | ||||
| CFO Denver, CO | 736 nm out, 24 nm southwest of the line, tower | no report just now | 5,515 ft | ||||
| FNL Fort Collins/Loveland, CO | 786 nm out, 15 nm southwest of the line, tower | no report just now | 5,020 ft | ||||
| HSG Thermopolis, WY | 1035 nm out, 5 nm southwest of the line | no report just now | 4,891 ft | ||||
| BZN Bozeman, MT | 1204 nm out, 9 nm southwest of the line, tower | no report just now | 4,473 ft | ||||
| HLN Helena, MT | destination | no report just now | 3,877 ft |
The highest airport on this list sits at 5,515 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, 3:38 am MDT (09:38 UTC)
HLN has no terminal forecast; use the nearest airport that does.
Temporary flight restrictions on the line or within 25 nm of it
- 6/8646 Arlington, TX, Thursday, October 15, 2026 through Friday, October 16, 2026 UTC 16 nm from the route, 189 nm along the route · drones kept away from a public gathering · starts Thursday 15 October · ZFW
Daylight
Sunset at IAH 6:55 pm CDT (23:55 UTC), at HLN 6:46 pm MDT (00:46 UTC) (civil twilight ends 7:17 pm MDT (01:17 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: George Bush Intcntl/Houston Airport, Helena Regional.