Rapid City Regional to Boeing Fld/King County International RAP → BFI
830 nautical miles (955 statute miles) west on a straight line, true course 291°, about 283° magnetic at the departure end (variation 8E). At 120 knots that is 6 h 20 min at the quickest height in today's winds (4,500 ft, a 11-knot tailwind), arriving about 2:53 am PDT (09:53 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 1C: thunderstorms (a convective SIGMET) up to 30,000 ft, moving from the southwest at 40 knots, until 10:55 pm MDT (04:55 UTC). Over the route from 59 to 59 nm out.
as issued
WSUS32 KKCI 120255 MKCC WST 120255 CONVECTIVE SIGMET 1C VALID UNTIL 0455Z SD ND MT WY FROM 30WSW DIK-50NW DPR-60WNW RAP-50ENE SHR-30WSW DIK AREA TS MOV FROM 22040KT. TOPS TO FL300.
- 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 504 nm of the route.
- AIRMET TANGO 4W: moderate turbulence above 18,000 ft from 18,000 ft to 36,000 ft. Over the route from 20 to 148 nm out.
- AIRMET TANGO 4W: moderate turbulence below 18,000 ft up to 18,000 ft. Over the route from 128 to 296 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). Near the route, 178 nm along the route.
- AIRMET ZULU 2C: moderate icing up to 23,000 ft. Over the route from 208 to 257 nm out.
- AIRMET SIERRA 1E: mountains obscured by cloud (due to mountains obscured by clouds, precipitation, mist). Over the route from 217 to 603 nm out.
- AIRMET ZULU 2C: moderate icing up to 20,000 ft. Over the route from 316 to 771 nm out.
- AIRMET TANGO 1W: moderate turbulence above 18,000 ft from 18,000 ft to 36,000 ft. Over the route from 375 to 583 nm out.
- AIRMET TANGO 1W: moderate turbulence above 18,000 ft from 18,000 ft to 39,000 ft. Over the last 158 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 RAP.
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 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 8 forecast points nearest it (RAP, MLS, BIL, DLN, LWS, GEG, YKM, SEA). 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 | 100° at 10 kt | −11 kt | 6 °C | 131 kt | 6 h 20 min | 2:53 am PDT (09:53 UTC) |
| 6,500 ft | 100° at 9 kt | −10 kt | 1 °C | 130 kt | 6 h 23 min | 2:56 am PDT (09:56 UTC) |
| 8,500 ft | 120° at 4 kt | −5 kt | -2 °C | 125 kt | 6 h 38 min | 3:11 am PDT (10:11 UTC) |
| 10,500 ft | 200° at 7 kt | −1 kt | -3 °C | 121 kt | 6 h 52 min | 3:25 am PDT (10:25 UTC) |
| 12,500 ft | 210° at 15 kt | +3 kt | -5 °C | 117 kt | 7 h 06 min | 3:39 am PDT (10:39 UTC) |
| 14,500 ft | 210° at 17 kt | +3 kt | -9 °C | 117 kt | 7 h 06 min | 3:39 am PDT (10:39 UTC) |
| 16,500 ft | 210° at 19 kt | +4 kt | -12 °C | 116 kt | 7 h 09 min | 3:42 am PDT (10:42 UTC) |
| 18,000 ft FL180 | 210° at 21 kt | +4 kt | -15 °C | 116 kt | 7 h 09 min | 3:42 am PDT (10:42 UTC) |
| 24,000 ft FL240 | 210° at 23 kt | +3 kt | -26 °C | 117 kt | 7 h 06 min | 3:39 am PDT (10:39 UTC) |
| 30,000 ft FL300 | 220° at 27 kt | +9 kt | -36 °C | 111 kt | 7 h 29 min | 4:02 am PDT (11:02 UTC) |
| 34,000 ft FL340 | 230° at 38 kt | +22 kt | -38 °C | 98 kt | 8 h 28 min | 5:01 am PDT (12:01 UTC) |
| 39,000 ft FL390 | 230° at 44 kt | +27 kt | -43 °C | 93 kt | 8 h 55 min | 5:28 am PDT (12:28 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 |
|---|---|---|---|---|---|---|---|---|---|---|
| RAP | used from 0 nm out; 25 nm from the line | 180/23 12° | 200/38 13° | 210/38 6° | 220/28 -10° | 230/34 -21° | 230/37 -36° | 250/52 -38° | 250/59 -46° | |
| MLS | used from 99 nm out; 100 nm from the line | 150/23 2° | 190/29 4° | 210/44 2° | 220/32 -10° | 210/36 -21° | 200/48 -37° | 230/63 -40° | 240/71 -47° | |
| BIL | used from 148 nm out; 85 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 346 nm out; 67 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° | ||
| LWS | used from 494 nm out; 92 nm from the line | 070/10 | 080/12 -2° | 030/12 -6° | 080/7 -10° | 170/34 -21° | 160/46 -32° | 200/33 -35° | 220/22 -35° | 230/18 -38° |
| GEG | used from 642 nm out; 45 nm from the line | 080/16 -2° | 050/17 -7° | 080/9 -10° | 190/33 -21° | 180/31 -32° | L/V -35° | L/V -37° | 270/8 -40° | |
| YKM | used from 692 nm out; 58 nm from the line | 070/10 | 040/15 -1° | 020/27 -8° | 030/25 -13° | 020/48 -20° | 010/83 -27° | 010/77 -37° | 010/49 -40° | 350/14 -41° |
| SEA | used from 791 nm out; 20 nm from the line | 050/7 | 050/11 1° | 050/12 -5° | 030/31 -7° | 010/61 -15° | 010/69 -26° | 360/73 -40° | 360/62 -47° | 330/21 -43° |
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 |
|---|---|---|---|---|---|---|---|
| RAP Rapid City, SD | departure | no report just now | 3,203 ft | ||||
| SPF Spearfish, SD | 40 nm out, 13 nm northeast of the line | no report just now | 3,933 ft | ||||
| GCC Gillette, WY | 109 nm out, 20 nm south of the line | no report just now | 4,365 ft | ||||
| SHR Sheridan, WY | 178 nm out, 17 nm south of the line | no report just now | 4,021 ft | ||||
| BIL Billings, MT | 257 nm out, 22 nm north of the line, tower | no report just now | 3,662 ft | ||||
| BZN Bozeman, MT | 356 nm out, 11 nm southwest of the line, tower | no report just now | 4,473 ft | ||||
| MSO Missoula, MT | 494 nm out, 25 nm north of the line, tower | no report just now | 3,205 ft | ||||
| PUW Pullman/Moscow, WA | 613 nm out, 12 nm south of the line | no report just now | 2,566 ft | ||||
| MWH Moses Lake, WA | 711 nm out, 4 nm east of the line, tower | no report just now | 1,188 ft | ||||
| ESW Easton, WA | 781 nm out, 10 nm south of the line | no report just now | 2,226 ft | ||||
| BFI Seattle, WA | destination | no report just now | 21 ft |
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 BFI when you get there the forecast at the estimated arrival, 2:53 am PDT (09:53 UTC)
BFI has no terminal forecast; use the nearest airport that does.
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 RAP 6:13 pm MDT (00:13 UTC), at BFI 6:27 pm PDT (01:27 UTC) (civil twilight ends 6:58 pm PDT (01:58 UTC)). At 120 knots the arrival at BFI is before sunrise there (7:23 am PDT (14:23 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: Rapid City Regional, Boeing Fld/King County International.