Plan a flight · Sun 8:37 pm PDT (03:37 UTC)

Boeing Fld/King County International to Northwest Arkansas Ntl Airport BFI → XNA

1,411 nautical miles (1,623 statute miles) east on a straight line, true course 108°, about 093° magnetic at the departure end (variation 15E). At 120 knots that is 9 h 40 min at the quickest height in today's winds (39,000 ft, a 26-knot tailwind), arriving about 8:17 am CDT (13:17 UTC). Right now BFI is VFR, wind calm; XNA is VFR, wind from the south-southwest (200°) at 3 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 2C: thunderstorms (a convective SIGMET) up to 31,000 ft, moving from the southwest at 40 knots, until 9:55 pm PDT (04:55 UTC). Over the route from 735 to 824 nm out.
as issued
```
WSUS32 KKCI 120255
MKCC WST 120255
CONVECTIVE SIGMET 2C
VALID UNTIL 0455Z
NE CO WY
FROM 40SE CZI-30WNW BFF-30SSE LAR-70NW LAR-40SE CZI
AREA TS MOV FROM 22040KT. TOPS TO FL310.
```
AIRMET TANGO 1W: moderate turbulence above 18,000 ft from 18,000 ft to 39,000 ft. Over the first 149 nm of the route.
AIRMET ZULU 2C: moderate icing up to 20,000 ft. Over the route from 60 to 348 nm out.
AIRMET SIERRA 1E: mountains obscured by cloud (due to mountains obscured by clouds, precipitation, mist). Over the route from 209 to 675 nm out.
AIRMET TANGO 1W: moderate turbulence above 18,000 ft from 18,000 ft to 36,000 ft. Over the route from 248 to 447 nm out.
AIRMET ZULU 2C: moderate icing up to 23,000 ft. Over the route from 377 to 695 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 387 to 656 nm out.
AIRMET TANGO 4W: moderate turbulence below 18,000 ft up to 18,000 ft. Over the route from 497 to 884 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). Over the route from 536 to 795 nm out.
AIRMET TANGO 4W: moderate turbulence above 18,000 ft from 18,000 ft to 36,000 ft. Over the route from 556 to 944 nm out.
AIRMET TANGO 5W: strong surface winds (30 knots or more) (due to sustained surface winds greater than 30 knots). Near the route, 695 nm along the route.
AIRMET TANGO 3W: 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 944 to 1281 nm out.

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

urgent CRJ2 at 7,000 ft, 22 nm northeast, 6:04 pm PDT (01:04 UTC): moderate turbulence, remarks: low-level wind shear dept runway 03 gain/loss unknown. 725 nm along the route, 22 nm northeast of the line.
as filed, and in English
```
CPR UUA /OV CPR035002/TM 0104/FL070/TP CRJ2/TB CONT MOD TURB/RM LLWS DEPT RY03 GAIN/LOSS UNKN
```
Report
an urgent report filed through CPR
Where
2 nm northeast (035°) of CPR
Time
01:04 UTC
Height
at 7,000 ft
Aircraft
CRJ2
Turbulence
continuous moderate turbulence
Remarks
low-level wind shear dept runway 03 gain/loss unknown
S22T at 15,000 ft, 9 nm northeast, 6:47 pm PDT (01:47 UTC): moderate rime icing above 15,000 ft, -5 °C. 546 nm along the route, 9 nm northeast 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. At the departure end, 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, 33 nm north, 6:52 pm PDT (01:52 UTC): remarks: zse. At the departure end, 33 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, 29 nm south, 5:42 pm PDT (00:42 UTC): remarks: zse. At the departure end, 29 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, 29 nm south, 5:42 pm PDT (00:42 UTC): remarks: zse. At the departure end, 29 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, 48 nm south, 6:18 pm PDT (01:18 UTC): light rime icing, -12 °C, remarks: zse. 99 nm along the route, 48 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, 4 nm west, 6:08 pm PDT (01:08 UTC): no turbulence, a trace of icing, overcast from 9,000 ft to 13,500 ft, -10 °C. 149 nm along the route, 4 nm west 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, 40 nm south, 5:56 pm PDT (00:56 UTC): overcast above 6,000 ft. 179 nm along the route, 40 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, 30 nm southwest, 5:54 pm PDT (00:54 UTC): overcast above 7,500 ft, remarks: braking action good during the descent runway 19. 536 nm along the route, 30 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
C56X at 13,000 ft, 45 nm southwest, 6:33 pm PDT (01:33 UTC): light chop turbulence, remarks: zdvwc. 795 nm along the route, 45 nm southwest of the line.
as filed, and in English
```
LAR UA /OV LAR/TM 0133/FL130/TP C56X/SK BASE160/TB OCNL CONS LGT CHOP/RM ZDVWC
```
Report
a routine report filed through LAR
Where
over LAR
Time
01:33 UTC
Height
at 13,000 ft
Aircraft
C56X
Sky
BASE160
Turbulence
occasional continuous light chop
Remarks
zdvwc

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 11 forecast points nearest it (SEA, YKM, LWS, DLN, LND, BFF, GLD, SLN, ICT, TUL, FSM). 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	210° at 19 kt	+1 kt		119 kt	11 h 51 min	10:28 am CDT (15:28 UTC)
7,500 ft	220° at 14 kt	−1 kt	4 °C	121 kt	11 h 40 min	10:17 am CDT (15:17 UTC)
9,500 ft	230° at 12 kt	−3 kt	4 °C	123 kt	11 h 28 min	10:05 am CDT (15:05 UTC)
11,500 ft	230° at 14 kt	−3 kt	1 °C	123 kt	11 h 28 min	10:05 am CDT (15:05 UTC)
13,500 ft	220° at 15 kt	−3 kt	-3 °C	123 kt	11 h 28 min	10:05 am CDT (15:05 UTC)
15,500 ft	220° at 17 kt	−4 kt	-7 °C	124 kt	11 h 23 min	10:00 am CDT (15:00 UTC)
17,500 ft	220° at 19 kt	−4 kt	-11 °C	124 kt	11 h 23 min	10:00 am CDT (15:00 UTC)
18,000 ft FL180	220° at 19 kt	−4 kt	-12 °C	124 kt	11 h 23 min	10:00 am CDT (15:00 UTC)
24,000 ft FL240	220° at 25 kt	−5 kt	-23 °C	125 kt	11 h 17 min	9:54 am CDT (14:54 UTC)
30,000 ft FL300	240° at 37 kt	−16 kt	-32 °C	136 kt	10 h 22 min	8:59 am CDT (13:59 UTC)
34,000 ft FL340	240° at 43 kt	−21 kt	-37 °C	141 kt	10 h	8:37 am CDT (13:37 UTC)
39,000 ft FL390	240° at 45 kt	−26 kt	-45 °C	146 kt	9 h 40 min	8:17 am CDT (13:17 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
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 50 nm out; 33 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 149 nm out; 54 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 348 nm out; 58 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°
LND	used from 546 nm out; 75 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°
BFF	used from 745 nm out; 100 nm from the line		180/28	220/33 15°	210/31 7°	230/32 -9°	220/41 -21°	220/40 -33°	240/47 -36°	250/54 -46°
GLD	used from 944 nm out; 70 nm from the line		230/49	230/42 15°	220/26 8°	240/18 -7°	230/27 -21°	240/62 -30°	240/61 -35°	250/57 -47°
SLN	used from 1093 nm out; 80 nm from the line	210/53	230/41 20°	240/26 14°	230/16 8°	240/25 -7°	240/35 -19°	250/61 -30°	260/65 -38°	260/56 -49°
ICT	used from 1192 nm out; 33 nm from the line	200/48	230/39 19°	240/24 14°	240/20 8°	240/22 -6°	250/31 -18°	250/61 -29°	260/58 -38°	270/54 -49°
TUL	used from 1291 nm out; 62 nm from the line	210/37	240/29 17°	260/15 14°	260/11 7°	240/22 -6°	250/29 -16°	270/45 -29°	270/47 -40°	280/44 -50°
FSM	used from 1391 nm out; 63 nm from the line	210/27	250/23 16°	250/20 13°	240/17 8°	250/18 -6°	260/31 -16°	280/42 -30°	280/44 -40°	290/38 -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	calm	10+ mi	none	21 ft	7:53 pm PDT (02:53 UTC)
MWH Moses Lake, WA	119 nm out, 22 nm northeast of the line, tower	VFR Sky: scattered clouds at 8,500 feet, overcast at 11,000 feet	from the north-northwest (330°) at 3 knots	10+ mi	11,000 ft	1,188 ft	02:52 UTC
LWS Lewiston, ID	228 nm out, 10 nm north of the line, tower	VFR Sky: overcast at 6,000 feet	from the west-northwest (300°) at 6 knots	10+ mi	6,000 ft	1,442 ft	02:56 UTC
SMN Salmon, ID	377 nm out, 7 nm southwest of the line	VFR Sky: a few clouds at 600 feet, a broken layer at 4,900 feet, overcast at 8,500 feet	from the north (010°) at 6 knots	10+ mi	4,900 ft	4,044 ft	03:19 UTC
WYS West Yellowstone, MT	497 nm out, 20 nm north of the line	low IFR Sky: overcast at 300 feet Weather: light snow, mist	variable at 5 knots	1.25 mi	300 ft	6,649 ft	03:15 UTC
RIW Riverton, WY	646 nm out, 14 nm southwest of the line	IFR Sky: a broken layer at 500 feet	from the northeast (050°) at 3 knots	10+ mi	500 ft	5,516 ft	03:22 UTC
CPR Casper, WY	725 nm out, 20 nm northeast of the line, tower	VFR Sky: a broken layer at 12,000 feet	calm	10+ mi	12,000 ft	5,344 ft	02:53 UTC
HEQ Holyoke, CO	954 nm out, 4 nm south of the line	marginal VFR Weather: haze	from the east (090°) at 5 knots	5 mi	none	3,729 ft	03:15 UTC
HLC Hill City, KS	1093 nm out, 4 nm west of the line	VFR	from the south-southwest (200°) at 17 knots, gusting to 26	10+ mi	none	2,238 ft	02:53 UTC
HUT Hutchinson, KS	1212 nm out, 14 nm southwest of the line, tower	VFR	from the south (170°) at 13 knots, gusting to 21	10+ mi	none	1,542 ft	02:52 UTC
IDP Independence, KS	1321 nm out, 1 nm southeast of the line	VFR	from the south (180°) at 11 knots	10+ mi	none	824 ft	03:15 UTC
XNA Fayetteville/Springdale/Rogers, AR	destination	VFR	from the south-southwest (200°) at 3 knots	10+ mi	none	1,288 ft	9:53 pm CDT (02:53 UTC)

The highest airport on this list sits at 6,649 ft; the ground between airports is higher still. Check the sectional chart for the terrain and the minimum safe heights along the line.

At XNA when you get there the forecast at the estimated arrival, 8:17 am CDT (13:17 UTC)

Wind from the south-southwest at 6 knots, visibility more than 6 miles, low-level wind shear, a few clouds at 5,000 feet VFR

The whole forecast for XNA

From Sun 7:00 pm CDT (00:00 UTC): wind from the south-southwest at 6 knots, visibility more than 6 miles, a few clouds at 25,000 feet
From Mon 1:00 am CDT (06:00 UTC): wind from the south-southwest at 6 knots, visibility more than 6 miles, low-level wind shear, a few clouds at 5,000 feet
From Mon 10:00 am CDT (15:00 UTC): wind from the south-southwest at 16 knots, gusting to 25, visibility more than 6 miles, clear skies

The forecast for BFI, the departure

From Sun 8:00 pm PDT (03:00 UTC): wind calm, visibility more than 6 miles, clear skies
From Mon 3:00 am PDT (10:00 UTC): wind calm, 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 XNA 6:45 pm CDT (23:45 UTC) (civil twilight ends 7:11 pm CDT (00:11 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 now, the southern 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, Northwest Arkansas Ntl Airport.