Plan a flight · Sun 4:32 pm PDT (23:32 UTC)

Yakima Air Trml/Mcallister Field to Boeing Fld/King County International YKM → BFI

92 nautical miles (106 statute miles) northwest on a straight line, true course 309°, about 293° magnetic at the departure end (variation 16E). At 120 knots that is 48 min at the quickest height in today's winds (4,500 ft, a 5-knot headwind), arriving about 5:20 pm PDT (00:20 UTC). Right now YKM is VFR, wind from the northeast (040°) at 9 knots; BFI is VFR, wind variable 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: 4 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 25,000 ft to 39,000 ft. Over the last 0 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 YKM.

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

E75L at 33,000 ft, 44 nm south, 1:40 pm PDT (20:40 UTC): light to moderate chop turbulence, remarks: zse. At the departure end, 44 nm south of the line.
as filed, and in English
```
DLS UA /OV LTJ053027/TM 2040/FL330/TP E75L/TB LGT OCNL MOD CHOP /RM ZSE
```
Report
a routine report filed through DLS
Where
27 nm northeast (053°) of LTJ
Time
20:40 UTC
Height
at 33,000 ft
Aircraft
E75L
Turbulence
light occasional moderate chop
Remarks
zse

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 2 forecast points nearest it (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	010° at 13 kt	+5 kt		115 kt	48 min	5:20 pm PDT (00:20 UTC)
6,500 ft	010° at 15 kt	+6 kt	0 °C	114 kt	48 min	5:20 pm PDT (00:20 UTC)
8,500 ft	020° at 19 kt	+5 kt	-6 °C	115 kt	48 min	5:20 pm PDT (00:20 UTC)
10,500 ft	030° at 21 kt	+4 kt	-9 °C	116 kt	48 min	5:20 pm PDT (00:20 UTC)
12,500 ft	030° at 24 kt	+4 kt	-13 °C	116 kt	48 min	5:20 pm PDT (00:20 UTC)
14,500 ft	020° at 33 kt	+9 kt	-16 °C	111 kt	50 min	5:22 pm PDT (00:22 UTC)
16,500 ft	020° at 43 kt	+13 kt	-18 °C	107 kt	52 min	5:24 pm PDT (00:24 UTC)
18,000 ft FL180	020° at 50 kt	+16 kt	-20 °C	104 kt	53 min	5:25 pm PDT (00:25 UTC)
24,000 ft FL240	010° at 80 kt	+39 kt	-28 °C	81 kt	1 h 08 min	5:40 pm PDT (00:40 UTC)
30,000 ft FL300	360° at 72 kt	+41 kt	-38 °C	79 kt	1 h 10 min	5:42 pm PDT (00:42 UTC)
34,000 ft FL340	010° at 48 kt	+26 kt	-40 °C	94 kt	59 min	5:31 pm PDT (00:31 UTC)
39,000 ft FL390	350° at 23 kt	+17 kt	-42 °C	103 kt	54 min	5:26 pm PDT (00:26 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
YKM	used from 0 nm out; 23 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°
SEA	used from 46 nm out; 21 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°

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
YKM Yakima, WA	departure	VFR Sky: overcast at 8,000 feet	from the northeast (040°) at 9 knots	10+ mi	8,000 ft	1,098 ft	3:53 pm PDT (22:53 UTC)
ESW Easton, WA	46 nm out, 15 nm northeast of the line	no report just now				2,226 ft
PLU Puyallup, WA	74 nm out, 20 nm southwest of the line	VFR Weather: light drizzle	from the north (010°) at 6 knots	10+ mi	none	537 ft	23:15 UTC
BFI Seattle, WA	destination	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)

The highest airport on this list sits at 2,226 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, 5:20 pm PDT (00:20 UTC)

Wind from the north-northwest at 9 knots, visibility more than 6 miles, scattered clouds at 20,000 feet VFR

The whole forecast for BFI

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

The forecast for YKM, the departure

From Sun 5:00 pm PDT (00:00 UTC): wind from the north-northeast at 9 knots, visibility more than 6 miles, a broken layer at 7,000 feet
From Sun 8:00 pm PDT (03:00 UTC): wind light and variable, visibility more than 6 miles, scattered clouds at 7,000 feet
From Sun 10:00 pm PDT (05:00 UTC): wind from the west-northwest at 6 knots, visibility more than 6 miles, clear skies
From Mon 11:00 am PDT (18:00 UTC): wind light and variable, 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 YKM 6:21 pm PDT (01:21 UTC), at BFI 6:27 pm PDT (01:27 UTC) (civil twilight ends 6:58 pm PDT (01:58 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, 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: Yakima Air Trml/Mcallister Field, Boeing Fld/King County International.