Plan a flight · Sun 7:43 pm PDT (02:43 UTC)

Boeing Fld/King County International to Dubois Municipal BFI → DUB

581 nautical miles (668 statute miles) east on a straight line, true course 110°, about 095° magnetic at the departure end (variation 15E). At 120 knots that is 4 h 22 min at the quickest height in today's winds (39,000 ft, a 13-knot tailwind), arriving about 1:05 am MDT (07:05 UTC), after sunset at the destination. Right now BFI is VFR, wind calm; DUB is IFR, wind from the southeast (130°) at 13 knots, gusting to 22. 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

AIRMET TANGO 1W: moderate turbulence above 18,000 ft from 18,000 ft to 39,000 ft. Over the first 138 nm of the route.
AIRMET ZULU 2C: moderate icing up to 16,000 ft. Over the route from 98 to 345 nm out.
AIRMET SIERRA 1E: mountains obscured by cloud (due to mountains obscured by clouds, precipitation, mist). Over the last 394 nm of the route.
AIRMET TANGO 4W: moderate turbulence above 18,000 ft from 18,000 ft to 36,000 ft. Over the last 295 nm of the route.
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 246 nm of the route.
AIRMET ZULU 3C: moderate icing up to 22,000 ft. Over the last 226 nm of the route.
AIRMET TANGO 4W: moderate turbulence below 18,000 ft up to 18,000 ft. Over the last 79 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 30 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 BFI.

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

B738 at 33,000 ft, 8 nm north, 4:57 pm PDT (23:57 UTC): moderate chop turbulence from 31,000 ft to 33,000 ft. 473 nm along the route, 8 nm north of the line.
as filed, and in English
```
IDA UA /OV DBS015030/TM 2357/FL330/TP B738/TB MOD CHOP 310-330 /ZLC
```
Report
a routine report filed through IDA
Where
30 nm north (015°) of DBS
Time
23:57 UTC
Height
at 33,000 ft
Aircraft
B738
Turbulence
moderate chop from 31,000 ft to 33,000 ft zlc
S22T at 15,000 ft, 22 nm north, 6:47 pm PDT (01:47 UTC): moderate rime icing above 15,000 ft, -5 °C. 551 nm along the route, 22 nm north of the line.
as filed, and in English
```
JAC UA /OV DNW010020/TM 0147/FL150/TP S22T/TA M05/IC MOD RIME 150 /ZLC
```
Report
a routine report filed through JAC
Where
20 nm north (010°) of DNW
Time
01:47 UTC
Height
at 15,000 ft
Aircraft
S22T
Temperature
−5 °C
Icing
moderate rime at 15,000 ft zlc
A321 at 13,500 ft, 28 nm south, 6:54 pm PDT (01:54 UTC): remarks: zse. 39 nm along the route, 28 nm south of the line.
as filed, and in English
```
SEA UA /OV SEA120045/TM 0154/FL135/TP A321/SK TOP130/RM ZSE
```
Report
a routine report filed through SEA
Where
45 nm southeast (120°) of SEA
Time
01:54 UTC
Height
at 13,500 ft
Aircraft
A321
Sky
TOP130
Remarks
zse
SB20 at 16,000 ft, 34 nm north, 6:52 pm PDT (01:52 UTC): remarks: zse. 39 nm along the route, 34 nm north of the line.
as filed, and in English
```
PAE UA /OV PAE075045/TM 0152/FL160/TP SB20/SK TOP120/RM ZSE
```
Report
a routine report filed through PAE
Where
45 nm east (075°) of PAE
Time
01:52 UTC
Height
at 16,000 ft
Aircraft
SB20
Sky
TOP120
Remarks
zse
PC12 at 15,000 ft, 28 nm south, 5:42 pm PDT (00:42 UTC): remarks: zse. 39 nm along the route, 28 nm south of the line.
as filed, and in English
```
YKM UA /OV YKM270050/TM 0042/FL150/TP PC12/SK TOP130/RM -ZSE
```
Report
a routine report filed through YKM
Where
50 nm west (270°) of YKM
Time
00:42 UTC
Height
at 15,000 ft
Aircraft
PC12
Sky
TOP130
Remarks
zse
PC12 at 13,000 ft, 28 nm south, 5:42 pm PDT (00:42 UTC): remarks: zse. 39 nm along the route, 28 nm south of the line.
as filed, and in English
```
YKM UA /OV YKM270050/TM 0042/FL130/TP PC12/SK TOP130/RM -ZSE
```
Report
a routine report filed through YKM
Where
50 nm west (270°) of YKM
Time
00:42 UTC
Height
at 13,000 ft
Aircraft
PC12
Sky
TOP130
Remarks
zse
C337 at 12,000 ft, 46 nm south, 6:18 pm PDT (01:18 UTC): light rime icing, -12 °C, remarks: zse. 98 nm along the route, 46 nm south of the line.
as filed, and in English
```
YKM UA /OV YKM155020/TM 0118/FL120/TP C337/TA M12/IC LGT RIME/RM ZSE
```
Report
a routine report filed through YKM
Where
20 nm southeast (155°) of YKM
Time
01:18 UTC
Height
at 12,000 ft
Aircraft
C337
Temperature
−12 °C
Icing
light rime
Remarks
zse
PC12 at 13,500 ft, 2 nm northwest, 6:08 pm PDT (01:08 UTC): no turbulence, a trace of icing, overcast from 9,000 ft to 13,500 ft, -10 °C. 148 nm along the route, 2 nm northwest of the line.
as filed, and in English
```
PSC UA /OV PSC360025/TM 0108/FL135/TP PC12/SK OVC090-TOP135/TA M10/TB NEG /IC TRACE RM 135-090
```
Report
a routine report filed through PSC
Where
25 nm north (360°) of PSC
Time
01:08 UTC
Height
at 13,500 ft
Aircraft
PC12
Sky
overcast from 9,000 ft, tops 13,500 ft
Temperature
−10 °C
Turbulence
none
Icing
trace remarks from 13,500 ft to 9,000 ft
PC12 at 6,000 ft, 36 nm south, 5:56 pm PDT (00:56 UTC): overcast above 6,000 ft. 177 nm along the route, 36 nm south of the line.
as filed, and in English
```
ALW UA /OV ALW200015/TM 0056/FL060/TP PC12/SK OVC060
```
Report
a routine report filed through ALW
Where
15 nm south (200°) of ALW
Time
00:56 UTC
Height
at 6,000 ft
Aircraft
PC12
Sky
overcast from 6,000 ft
A320 descending, 18 nm southwest, 5:54 pm PDT (00:54 UTC): overcast above 7,500 ft, remarks: braking action good during the descent runway 19. 541 nm along the route, 18 nm southwest of the line.
as filed, and in English
```
JAC UA /OV JAC/TM 0054/FLUNKN/TP A320/SK OVC075/RM BRAKING ACTION GOOD DURD RY19
```
Report
a routine report filed through JAC
Where
over JAC
Time
00:54 UTC
Height
height not given
Aircraft
A320
Sky
overcast from 7,500 ft
Remarks
braking action good during the descent runway 19
PC12 at 15,000 ft, 43 nm southwest, 4:47 pm PDT (23:47 UTC): light rime icing above 15,000 ft. 541 nm along the route, 43 nm southwest of the line.
as filed, and in English
```
JAC UA /OV JAC200025/TM 2347/FL150/TP PC12/IC LGT RIME 150 /ZLC
```
Report
a routine report filed through JAC
Where
25 nm south (200°) of JAC
Time
23:47 UTC
Height
at 15,000 ft
Aircraft
PC12
Icing
light rime at 15,000 ft zlc

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 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 6 forecast points nearest it (SEA, YKM, LWS, DLN, PIH, LND). A plus sign is a headwind, a minus sign a tailwind.

Height	Average wind	Head- or tailwind	Temperature	Ground speed	Time en route	Arrival
3,500 ft	070° at 10 kt	+7 kt		113 kt	5 h 08 min	1:51 am MDT (07:51 UTC)
5,500 ft	060° at 10 kt	+7 kt		113 kt	5 h 08 min	1:51 am MDT (07:51 UTC)
7,500 ft	050° at 7 kt	+4 kt	-4 °C	116 kt	5 h 01 min	1:44 am MDT (07:44 UTC)
9,500 ft	030° at 7 kt	+1 kt	-6 °C	119 kt	4 h 53 min	1:36 am MDT (07:36 UTC)
11,500 ft	350° at 2 kt	−1 kt	-7 °C	121 kt	4 h 48 min	1:31 am MDT (07:31 UTC)
13,500 ft	220° at 2 kt	0	-10 °C	120 kt	4 h 50 min	1:33 am MDT (07:33 UTC)
15,500 ft	200° at 6 kt	+2 kt	-13 °C	118 kt	4 h 55 min	1:38 am MDT (07:38 UTC)
17,500 ft	190° at 10 kt	+4 kt	-17 °C	116 kt	5 h 01 min	1:44 am MDT (07:44 UTC)
18,000 ft FL180	190° at 11 kt	+4 kt	-18 °C	116 kt	5 h 01 min	1:44 am MDT (07:44 UTC)
24,000 ft FL240	190° at 16 kt	+6 kt	-28 °C	114 kt	5 h 06 min	1:49 am MDT (07:49 UTC)
30,000 ft FL300	230° at 21 kt	−7 kt	-35 °C	127 kt	4 h 34 min	1:17 am MDT (07:17 UTC)
34,000 ft FL340	230° at 28 kt	−9 kt	-37 °C	129 kt	4 h 30 min	1:13 am MDT (07:13 UTC)
39,000 ft FL390	230° at 34 kt	−13 kt	-41 °C	133 kt	4 h 22 min	1:05 am MDT (07:05 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
SEA	used from 0 nm out; 24 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°
YKM	used from 49 nm out; 32 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°
LWS	used from 148 nm out; 57 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°
DLN	used from 345 nm out; 65 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°
PIH	used from 492 nm out; 98 nm from the line		L/V	240/13 1°	240/15 -3°	210/42 -15°	200/70 -25°	220/74 -29°	220/71 -36°	220/62 -43°
LND	used from 541 nm out; 80 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°

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 6,000 feet	calm	10+ mi	none	21 ft	6:53 pm PDT (01:53 UTC)
ESW Easton, WA	49 nm out, 1 nm west of the line	no report just now				2,226 ft
ELN Ellensburg, WA	79 nm out, 3 nm southwest of the line	VFR Sky: overcast at 9,000 feet	from the northeast (040°) at 7 knots	10+ mi	9,000 ft	1,763 ft	01:53 UTC
PSC Pasco, WA	148 nm out, 25 nm south of the line, tower	VFR Sky: overcast at 9,000 feet	from the north (010°) at 7 knots	10+ mi	9,000 ft	410 ft	01:53 UTC
LWS Lewiston, ID	226 nm out, 15 nm northeast of the line, tower	VFR Sky: overcast at 6,000 feet	from the west-northwest (300°) at 8 knots	10+ mi	6,000 ft	1,442 ft	01:56 UTC
GIC Grangeville, ID	276 nm out, 8 nm north of the line	VFR Sky: overcast at 3,100 feet	from the north-northwest (340°) at 3 knots	10+ mi	3,100 ft	3,313 ft	02:35 UTC
SMN Salmon, ID	374 nm out, 4 nm east of the line	VFR Sky: a few clouds at 1,800 feet, overcast at 3,900 feet Weather: unknown precipitation	from the north (350°) at 8 knots	10+ mi	3,900 ft	4,044 ft	01:56 UTC
DIJ Driggs, ID	522 nm out, 18 nm southwest of the line	VFR Sky: a few clouds at 2,200 feet, a broken layer at 3,800 feet, overcast at 4,800 feet Weather: light rain	from the north-northwest (330°) at 9 knots	7 mi	3,800 ft	6,257 ft	01:56 UTC
JAC Jackson, WY	541 nm out, 19 nm southwest of the line, tower	VFR Sky: a few clouds at 800 feet, a broken layer at 3,100 feet, overcast at 4,800 feet Weather: rain, mist	from the south (170°) at 6 knots	6 mi	3,100 ft	6,451 ft	02:24 UTC
DUB Dubois, WY	destination	IFR Sky: overcast at 500 feet Weather: light rain	from the southeast (130°) at 13 knots, gusting to 22	5 mi	500 ft	7,298 ft	8:35 pm MDT (02:35 UTC)

The highest airport on this list sits at 7,298 ft; the ground between airports is higher still. Check the sectional chart for the terrain and the minimum safe heights along the line.

At DUB when you get there the forecast at the estimated arrival, 1:05 am MDT (07:05 UTC)

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

The forecast for BFI, the departure

From Sun 5:00 pm PDT (00:00 UTC): wind from the north-northwest at 8 knots, gusting to 18, visibility more than 6 miles, a few clouds at 5,000 feet
From Sun 7:00 pm PDT (02:00 UTC): wind light and variable, visibility more than 6 miles, clear skies
From Mon 3:00 am PDT (10:00 UTC): wind light and variable, 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
From Mon 12:00 pm PDT (19:00 UTC): wind from the west-southwest at 3 knots, visibility more than 6 miles, clear skies
From Mon 2:00 pm PDT (21:00 UTC): wind from the west at 5 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 DUB 6:40 pm MDT (00:40 UTC) (civil twilight ends 7:09 pm MDT (01:09 UTC)). At 120 knots the arrival at DUB is before sunrise there (7:29 am MDT (13:29 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, Dubois Municipal.