Plan a flight · Sun 4:35 pm PDT (23:35 UTC)

Boeing Fld/King County International to Rosebud Sioux Tribal Airport BFI → SUO

936 nautical miles (1,077 statute miles) east on a straight line, true course 098°, about 083° magnetic at the departure end (variation 15E). At 120 knots that is 6 h 09 min at the quickest height in today's winds (39,000 ft, a 32-knot tailwind), arriving about 12:44 am CDT (05:44 UTC), after sunset at the destination. Right now BFI is VFR, wind variable at 4 knots; SUO is marginal VFR, wind from the east-northeast (060°) at 4 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 W65W: thunderstorms (a convective SIGMET) up to 32,000 ft, moving from the southwest at 40 knots, until 5:55 pm PDT (00:55 UTC). Over the route from 618 to 717 nm out.
as issued
```
WSUS33 KKCI 112255
MKCW WST 112255
CONVECTIVE SIGMET 65W
VALID UNTIL 0055Z
MT WY
FROM 40NW SHR-80NE CZI-40SSE BOY-60ENE JAC-40NW SHR
AREA TS MOV FROM 22040KT. TOPS TO FL320.
```
AIRMET TANGO 1W: moderate turbulence above 18,000 ft from 25,000 ft to 39,000 ft. Over the first 0 nm of the route.
AIRMET ZULU 2C: moderate icing up to 14,000 ft. Over the route from 120 to 339 nm out.
AIRMET SIERRA 1E: mountains obscured by cloud (due to mountains obscured by clouds, precipitation, mist). Over the route from 189 to 637 nm out.
AIRMET TANGO 4W: moderate turbulence above 18,000 ft from 18,000 ft to 36,000 ft. Over the route from 259 to 837 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 route from 299 to 667 nm out.
AIRMET TANGO 4W: moderate turbulence below 18,000 ft up to 18,000 ft. Over the route from 518 to 667 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, 578 nm along 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 BFI.

Pilot reports along the route within 50 nm of the line, last three hours, the serious ones first

E75L at 14,000 ft, 7 nm northeast, 4:22 pm PDT (23:22 UTC): moderate turbulence from 14,000 ft to 21,000 ft, remarks: during the climb zlc. 339 nm along the route, 7 nm northeast of the line.
as filed, and in English
```
MSO UA /OV 32S/TM 2322/FL140/TP E75L/TB MOD 140-210/RM DURC /ZLC
```
Report
a routine report filed through MSO
Where
over 32S
Time
23:22 UTC
Height
at 14,000 ft
Aircraft
E75L
Turbulence
moderate from 14,000 ft to 21,000 ft
Remarks
during the climb zlc
C172 at 5,500 ft, 22 nm south, 3:17 pm PDT (22:17 UTC): a trace of rime icing, 0 °C, remarks: zse. 179 nm along the route, 22 nm south of the line.
as filed, and in English
```
PUW UA /OV PUW250030/TM 2217/FL055/TP C172/TA 00/IC TRACE RIME/RM -ZSE
```
Report
a routine report filed through PUW
Where
30 nm west (250°) of PUW
Time
22:17 UTC
Height
at 5,500 ft
Aircraft
C172
Temperature
0 °C
Icing
trace rime
Remarks
zse
B739 at 3,700 ft, 27 nm north, 2:58 pm PDT (21:58 UTC): overcast above 3,700 ft, remarks: during the descent ils runway 12. 339 nm along the route, 27 nm north of the line.
as filed, and in English
```
MSO UA /OV MSO/TM 2158/FL037/TP B739/SK OVC037/RM DURD ILS RY 12
```
Report
a routine report filed through MSO
Where
over MSO
Time
21:58 UTC
Height
at 3,700 ft
Aircraft
B739
Sky
overcast from 3,700 ft
Remarks
during the descent ils runway 12
B739 at 9,000 ft, 27 nm north, 1:41 pm PDT (20:41 UTC): overcast from 5,900 ft to 9,000 ft, remarks: during the descent ils runway 12. 339 nm along the route, 27 nm north of the line.
as filed, and in English
```
MSO UA /OV MSO/TM 2041/FL090/TP B739/SK OVC059-TOP090/RM DURD ILS RY 12
```
Report
a routine report filed through MSO
Where
over MSO
Time
20:41 UTC
Height
at 9,000 ft
Aircraft
B739
Sky
overcast from 5,900 ft, tops 9,000 ft
Remarks
during the descent ils runway 12
B738 at 24,000 ft, 6 nm south, 4:13 pm PDT (23:13 UTC): remarks: snow top flight level at 24,000 ft zlc. 438 nm along the route, 6 nm south of the line.
as filed, and in English
```
BZN UA /OV BZN270030/TM 2313/FL240/TP B738/RM SN TOP FL 240 /ZLC
```
Report
a routine report filed through BZN
Where
30 nm west (270°) of BZN
Time
23:13 UTC
Height
at 24,000 ft
Aircraft
B738
Remarks
snow top flight level at 24,000 ft zlc
B738 descending, 7 nm south, 2:06 pm PDT (21:06 UTC): remarks: field in sight at mins rnav Y runway 12. 468 nm along the route, 7 nm south of the line.
as filed, and in English
```
BZN UA /OV BZN/TM 2106/FLDURD/TP B738/WX 2SM/RM FIELD IN SIGHT AT MINS RNAV Y RWY 12
```
Report
a routine report filed through BZN
Where
over BZN
Time
21:06 UTC
Height
during the descent
Aircraft
B738
Weather
2SM
Remarks
field in sight at mins rnav Y runway 12
B738 descending, 7 nm south, 2:05 pm PDT (21:05 UTC): remarks: visibility at mins rnav Z runway 12. 468 nm along the route, 7 nm south of the line.
as filed, and in English
```
BZN UA /OV BZN/TM 2105/FLDURD/TP B738/RM VIS AT MINS RNAV Z RWY 12
```
Report
a routine report filed through BZN
Where
over BZN
Time
21:05 UTC
Height
during the descent
Aircraft
B738
Remarks
visibility at mins rnav Z runway 12
E75L descending, 7 nm south, 1:57 pm PDT (20:57 UTC): remarks: visibility at minimums rnav Z. 468 nm along the route, 7 nm south of the line.
as filed, and in English
```
BZN UA /OV BZN/TM 2057/FLDURD/TP E75L/SK 050/RM VIS AT MINIMUMS RNAV Z
```
Report
a routine report filed through BZN
Where
over BZN
Time
20:57 UTC
Height
during the descent
Aircraft
E75L
Sky
at 5,000 ft
Remarks
visibility at minimums rnav Z
BE9T at 17,500 ft, 35 nm south, 3:40 pm PDT (22:40 UTC): no turbulence, light icing, -6 °C, remarks: ZDVWC-22. 697 nm along the route, 35 nm south of the line.
as filed, and in English
```
GCC UA /OV CZI020012/TM 2240/FL175/TP BE9T/TA M06/TB NEG/IC LGT MIX /RM ZDVWC-22
```
Report
a routine report filed through GCC
Where
12 nm north (020°) of CZI
Time
22:40 UTC
Height
at 17,500 ft
Aircraft
BE9T
Temperature
−6 °C
Turbulence
none
Icing
light mix
Remarks
ZDVWC-22
A21N at 35,000 ft, 15 nm southwest, 3:47 pm PDT (22:47 UTC): no turbulence, remarks: ZDVWC-32. 727 nm along the route, 15 nm southwest of the line.
as filed, and in English
```
GCC UA /OV GCC/TM 2247/FL350/TP A21N/TB NEG /RM ZDVWC-32
```
Report
a routine report filed through GCC
Where
over GCC
Time
22:47 UTC
Height
at 35,000 ft
Aircraft
A21N
Turbulence
none
Remarks
ZDVWC-32
B752 at 35,000 ft, 46 nm southeast, 2:14 pm PDT (21:14 UTC): no turbulence, remarks: visual conditions ZDVWC-35. At the destination end, 46 nm southeast of the line.
as filed, and in English
```
ANW UA /OV ANW270015/TM 2114/FL350/TP B752/TB NEG/RM VMC ZDVWC-35
```
Report
a routine report filed through ANW
Where
15 nm west (270°) of ANW
Time
21:14 UTC
Height
at 35,000 ft
Aircraft
B752
Turbulence
none
Remarks
visual conditions ZDVWC-35

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 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 9 forecast points nearest it (SEA, YKM, GEG, LWS, DLN, BIL, MLS, RAP, PIR). A plus sign is a headwind, a minus sign a tailwind.

Height	Average wind	Head- or tailwind	Temperature	Ground speed	Time en route	Arrival
5,500 ft	080° at 13 kt	+12 kt	10 °C	108 kt	8 h 40 min	3:15 am CDT (08:15 UTC)
7,500 ft	090° at 9 kt	+10 kt	2 °C	110 kt	8 h 31 min	3:06 am CDT (08:06 UTC)
9,500 ft	120° at 6 kt	+7 kt	-1 °C	113 kt	8 h 17 min	2:52 am CDT (07:52 UTC)
11,500 ft	190° at 10 kt	+3 kt	-3 °C	117 kt	8 h	2:35 am CDT (07:35 UTC)
13,500 ft	200° at 13 kt	0	-6 °C	120 kt	7 h 48 min	2:23 am CDT (07:23 UTC)
15,500 ft	210° at 15 kt	−2 kt	-10 °C	122 kt	7 h 40 min	2:15 am CDT (07:15 UTC)
17,500 ft	210° at 17 kt	−4 kt	-14 °C	124 kt	7 h 33 min	2:08 am CDT (07:08 UTC)
18,000 ft FL180	220° at 18 kt	−5 kt	-15 °C	125 kt	7 h 29 min	2:04 am CDT (07:04 UTC)
24,000 ft FL240	230° at 29 kt	−13 kt	-24 °C	133 kt	7 h 02 min	1:37 am CDT (06:37 UTC)
30,000 ft FL300	220° at 35 kt	−12 kt	-36 °C	132 kt	7 h 05 min	1:40 am CDT (06:40 UTC)
34,000 ft FL340	230° at 44 kt	−23 kt	-41 °C	143 kt	6 h 33 min	1:08 am CDT (06:08 UTC)
39,000 ft FL390	240° at 47 kt	−32 kt	-45 °C	152 kt	6 h 09 min	12:44 am CDT (05:44 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
SEA	used from 0 nm out; 25 nm from the line	360/9	350/10 1°	010/10 -5°	030/20 -11°	020/60 -17°	010/86 -26°	360/90 -40°	010/68 -42°	360/31 -43°
YKM	used from 50 nm out; 46 nm from the line	030/16	020/18 0°	030/30 -8°	030/23 -13°	020/40 -23°	010/73 -29°	010/54 -36°	360/29 -37°	330/16 -40°
GEG	used from 149 nm out; 41 nm from the line		050/18 -2°	060/19 -8°	L/V -11°	160/11 -24°	190/17 -31°	200/19 -35°	220/14 -37°	250/11 -41°
LWS	used from 199 nm out; 31 nm from the line	010/5	050/14 -2°	040/12 -6°	160/7 -10°	190/30 -22°	200/54 -27°	200/48 -35°	210/40 -37°	230/32 -41°
DLN	used from 349 nm out; 72 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°
BIL	used from 498 nm out; 59 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°
MLS	used from 647 nm out; 98 nm from the line		120/22 5°	170/18 4°	200/33 1°	230/49 -10°	230/58 -21°	220/54 -37°	230/64 -44°	250/74 -49°
RAP	used from 697 nm out; 108 nm from the line		120/15 12°	180/22 11°	220/26 5°	230/35 -9°	240/40 -22°	240/50 -37°	240/51 -41°	240/47 -47°
PIR	used from 896 nm out; 74 nm from the line		L/V 17°	230/13 12°	220/22 6°	250/31 -9°	250/34 -21°	240/50 -35°	230/61 -43°	240/62 -51°

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
BFI Seattle, WA	departure	VFR Sky: a few clouds at 5,000 feet	variable at 4 knots	10+ mi	none	21 ft	3:53 pm PDT (22:53 UTC)
EAT Wenatchee, WA	90 nm out, 7 nm northwest of the line	VFR Sky: overcast at 8,500 feet	from the northeast (040°) at 9 knots, gusting to 25	10+ mi	8,500 ft	1,248 ft	22:55 UTC
MWH Moses Lake, WA	120 nm out, 3 nm east of the line, tower	VFR Sky: a few clouds at 11,000 feet	from the northeast (050°) at 17 knots, gusting to 24	10+ mi	none	1,188 ft	22:52 UTC
PUW Pullman/Moscow, WA	219 nm out, 10 nm southwest of the line	VFR Sky: overcast at 5,500 feet	from the north-northeast (020°) at 9 knots	10+ mi	5,500 ft	2,566 ft	22:53 UTC
HRF Hamilton, MT	349 nm out, 12 nm southwest of the line	marginal VFR Sky: a few clouds at 900 feet, a broken layer at 1,300 feet, a broken layer at 1,900 feet Weather: mist, unknown precipitation	from the north (350°) at 14 knots, gusting to 19	3 mi	1,300 ft	3,635 ft	23:10 UTC
BZN Bozeman, MT	468 nm out, 7 nm south of the line, tower	low IFR Sky: a few clouds at 300 feet, overcast at 1,100 feet Weather: snow, fog	calm	0.5 mi	1,100 ft	4,473 ft	22:56 UTC
LVM Livingston, MT	498 nm out, 4 nm southeast of the line	IFR Sky: a broken layer at 500 feet, overcast at 2,200 feet Weather: light snow, mist	from the east (090°) at 15 knots	1.75 mi	500 ft	4,659 ft	22:53 UTC
SHR Sheridan, WY	657 nm out, 11 nm south of the line	IFR Sky: a broken layer at 700 feet, overcast at 1,300 feet Weather: light rain	from the east-northeast (060°) at 4 knots	9 mi	700 ft	4,021 ft	23:07 UTC
RAP Rapid City, SD	827 nm out, 8 nm northeast of the line, tower	marginal VFR Sky: a broken layer at 1,900 feet	from the north-northeast (030°) at 8 knots	10+ mi	1,900 ft	3,203 ft	23:05 UTC
SUO Rosebud, SD	destination	marginal VFR Sky: overcast at 1,000 feet	from the east-northeast (060°) at 4 knots	8 mi	1,000 ft	2,724 ft	6:15 pm CDT (23:15 UTC)

The highest airport on this list sits at 4,659 ft; the ground between airports is higher still. Check the sectional chart for the terrain and the minimum safe heights along the line.

At SUO when you get there the forecast at the estimated arrival, 12:44 am CDT (05:44 UTC)

SUO has no terminal forecast; use the nearest airport that does.

The forecast for BFI, the departure

From Sun 11:00 am PDT (18:00 UTC): wind from the north at 5 knots, visibility more than 6 miles, a few clouds at 10,000 feet
From Sun 2:00 pm PDT (21:00 UTC): wind from the north-northwest at 9 knots, visibility more than 6 miles, scattered clouds at 20,000 feet
From Sun 7:00 pm PDT (02:00 UTC): wind light and variable, visibility more than 6 miles, clear skies
From Mon 2:00 am PDT (09:00 UTC): wind from the southeast at 2 knots, visibility more than 6 miles, patches of fog, clear skies
From Mon 9:00 am PDT (16:00 UTC): wind from the south-southeast at 3 knots, visibility more than 6 miles, clear skies

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 BFI 6:27 pm PDT (01:27 UTC), at SUO 7:05 pm CDT (00:05 UTC) (civil twilight ends 7:34 pm CDT (00:34 UTC)). At 120 knots the arrival at SUO is before sunrise there (7:53 am CDT (12:53 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

Radar now, the Pacific Northwest · loop National Weather Service

Radar now, the northern Rockies · loop National Weather Service

Radar, the whole country · loop National Weather Service

Surface analysis now Weather Prediction Center

Forecast chart, 12 hours ahead Weather Prediction Center

Forecast chart, 24 hours ahead Weather Prediction Center

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: Boeing Fld/King County International, Rosebud Sioux Tribal Airport.