Boeing Fld/King County International to Renton Municipal BFI → RNT
4 nautical miles (5 statute miles) southeast on a straight line, true course 122°, about 107° magnetic at the departure end (variation 15E). At 120 knots that is 1 min at the quickest height in today's winds (30,000 ft, a 48-knot tailwind), arriving about 4:30 pm PDT (23:30 UTC). Right now BFI is VFR, wind variable at 4 knots; RNT is VFR, wind from the north-northwest (340°) at 11 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 whole 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
Not fetched just now.
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 1 forecast point nearest it (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 |
|---|---|---|---|---|---|---|
| 3,500 ft | 360° at 9 kt | −5 kt | 125 kt | 2 min | 4:31 pm PDT (23:31 UTC) | |
| 5,500 ft | 350° at 10 kt | −6 kt | 126 kt | 2 min | 4:31 pm PDT (23:31 UTC) | |
| 7,500 ft | 360° at 10 kt | −5 kt | -2 °C | 125 kt | 2 min | 4:31 pm PDT (23:31 UTC) |
| 9,500 ft | 020° at 12 kt | −3 kt | -6 °C | 123 kt | 2 min | 4:31 pm PDT (23:31 UTC) |
| 11,500 ft | 030° at 18 kt | −1 kt | -10 °C | 121 kt | 2 min | 4:31 pm PDT (23:31 UTC) |
| 13,500 ft | 020° at 30 kt | −4 kt | -12 °C | 124 kt | 2 min | 4:31 pm PDT (23:31 UTC) |
| 15,500 ft | 020° at 43 kt | −8 kt | -14 °C | 128 kt | 2 min | 4:31 pm PDT (23:31 UTC) |
| 17,500 ft | 020° at 57 kt | −12 kt | -16 °C | 132 kt | 2 min | 4:31 pm PDT (23:31 UTC) |
| 18,000 ft FL180 | 020° at 60 kt | −13 kt | -17 °C | 133 kt | 2 min | 4:31 pm PDT (23:31 UTC) |
| 24,000 ft FL240 | 010° at 86 kt | −33 kt | -26 °C | 153 kt | 2 min | 4:31 pm PDT (23:31 UTC) |
| 30,000 ft FL300 | 360° at 90 kt | −48 kt | -40 °C | 168 kt | 1 min | 4:30 pm PDT (23:30 UTC) |
| 34,000 ft FL340 | 010° at 68 kt | −26 kt | -42 °C | 146 kt | 2 min | 4:31 pm PDT (23:31 UTC) |
| 39,000 ft FL390 | 360° at 31 kt | −17 kt | -43 °C | 137 kt | 2 min | 4:31 pm PDT (23:31 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; 4 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 |
|---|---|---|---|---|---|---|---|
| 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) |
| RNT Renton, WA | destination | VFR | from the north-northwest (340°) at 11 knots | 10+ mi | none | 32 ft | 3:53 pm PDT (22:53 UTC) |
The highest airport on this list sits at 32 ft; the ground between airports is higher still. Check the sectional chart for the terrain and the minimum safe heights along the line.
At RNT when you get there the forecast at the estimated arrival, 4:30 pm PDT (23:30 UTC)
RNT 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 RNT 6:26 pm PDT (01:26 UTC) (civil twilight ends 6:57 pm PDT (01:57 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: Boeing Fld/King County International, Renton Municipal.