San Antonio International to Gary/Chicago International SAT → GYY
903 nautical miles (1,039 statute miles) northeast on a straight line, true course 034°, about 030° magnetic at the departure end (variation 4E). At 120 knots that is 6 h 19 min at the quickest height in today's winds (3,500 ft, a 23-knot tailwind), arriving about 4:25 am CDT (09:25 UTC), after sunset at the destination. 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
No SIGMET or AIRMET covers any part of this route right now.
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 SAT.
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 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 8 forecast points nearest it (SAT, CLL, DAL, FSM, SGF, STL, SPI, JOT). 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 | 220° at 22 kt | −23 kt | 143 kt | 6 h 19 min | 4:25 am CDT (09:25 UTC) | |
| 5,500 ft | 230° at 21 kt | −20 kt | 140 kt | 6 h 27 min | 4:33 am CDT (09:33 UTC) | |
| 7,500 ft | 240° at 19 kt | −18 kt | 14 °C | 138 kt | 6 h 33 min | 4:39 am CDT (09:39 UTC) |
| 9,500 ft | 240° at 17 kt | −16 kt | 11 °C | 136 kt | 6 h 38 min | 4:44 am CDT (09:44 UTC) |
| 11,500 ft | 250° at 15 kt | −13 kt | 8 °C | 133 kt | 6 h 47 min | 4:53 am CDT (09:53 UTC) |
| 13,500 ft | 250° at 16 kt | −13 kt | 4 °C | 133 kt | 6 h 47 min | 4:53 am CDT (09:53 UTC) |
| 15,500 ft | 250° at 17 kt | −14 kt | -1 °C | 134 kt | 6 h 44 min | 4:50 am CDT (09:50 UTC) |
| 17,500 ft | 250° at 19 kt | −15 kt | -5 °C | 135 kt | 6 h 41 min | 4:47 am CDT (09:47 UTC) |
| 18,000 ft FL180 | 250° at 19 kt | −15 kt | -6 °C | 135 kt | 6 h 41 min | 4:47 am CDT (09:47 UTC) |
| 24,000 ft FL240 | 260° at 24 kt | −17 kt | -16 °C | 137 kt | 6 h 35 min | 4:41 am CDT (09:41 UTC) |
| 30,000 ft FL300 | 280° at 33 kt | −13 kt | -31 °C | 133 kt | 6 h 47 min | 4:53 am CDT (09:53 UTC) |
| 34,000 ft FL340 | 280° at 40 kt | −15 kt | -40 °C | 135 kt | 6 h 41 min | 4:47 am CDT (09:47 UTC) |
| 39,000 ft FL390 | 300° at 43 kt | −7 kt | -51 °C | 127 kt | 7 h 07 min | 5:13 am CDT (10:13 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 |
|---|---|---|---|---|---|---|---|---|---|---|
| SAT | used from 0 nm out; 25 nm from the line | 150/26 | 180/18 19° | 180/18 14° | 200/14 9° | 230/16 -6° | 210/9 -13° | 270/8 -29° | 280/6 -39° | 340/19 -51° |
| CLL | used from 50 nm out; 68 nm from the line | 170/22 | 170/26 18° | 200/15 14° | 240/13 8° | 240/15 -5° | 260/17 -13° | 290/27 -29° | 290/22 -40° | 320/30 -51° |
| DAL | used from 149 nm out; 57 nm from the line | 190/29 | 220/23 17° | 220/17 13° | 250/18 8° | 230/18 -5° | 240/18 -15° | 270/34 -29° | 280/33 -39° | 300/36 -51° |
| FSM | used from 298 nm out; 87 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° |
| SGF | used from 496 nm out; 56 nm from the line | 230/33 | 230/28 15° | 250/20 13° | 240/18 7° | 250/20 -6° | 250/24 -17° | 280/42 -31° | 280/49 -40° | 290/46 -51° |
| STL | used from 595 nm out; 64 nm from the line | 250/24 | 250/24 16° | 260/23 9° | 270/16 6° | 260/25 -6° | 270/29 -19° | 290/34 -33° | 290/48 -41° | 290/54 -51° |
| SPI | used from 744 nm out; 18 nm from the line | 220/21 | 250/23 16° | 260/27 9° | 270/14 6° | 270/23 -7° | 270/31 -19° | 270/28 -33° | 290/48 -42° | 300/55 -52° |
| JOT | used from 794 nm out; 62 nm from the line | 250/23 | 270/22 15° | 250/16 10° | 240/9 4° | 280/22 -7° | 280/29 -19° | 300/29 -34° | 290/50 -43° | 300/64 -52° |
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 |
|---|---|---|---|---|---|---|---|
| SAT San Antonio, TX | departure | no report just now | 809 ft | ||||
| GTU Georgetown, TX | 79 nm out, 4 nm northwest of the line, tower | no report just now | 789 ft | ||||
| CNW Waco, TX | 149 nm out, 11 nm west of the line, tower | no report just now | 470 ft | ||||
| GVT Greenville, TX | 248 nm out, 17 nm northwest of the line, tower | no report just now | 534 ft | ||||
| LBR Clarksville, TX | 298 nm out, 6 nm east of the line | no report just now | 440 ft | ||||
| MEZ Mena, AR | 367 nm out, 8 nm east of the line | no report just now | 1,079 ft | ||||
| BBG Branson, MO | 496 nm out, 23 nm northwest of the line, tower | no report just now | 1,302 ft | ||||
| TVB Cabool, MO | 555 nm out, 2 nm north of the line | no report just now | 1,220 ft | ||||
| STL St Louis, MO | 684 nm out, 3 nm southeast of the line, tower | no report just now | 617 ft | ||||
| BMI Bloomington/Normal, IL | 803 nm out, 9 nm northwest of the line, tower | no report just now | 871 ft | ||||
| LOT Chicago/Romeoville, IL | 883 nm out, 23 nm northwest of the line, tower | no report just now | 679 ft | ||||
| GYY Gary/Chicago, IN | destination | no report just now | 596 ft |
The highest airport on this list sits at 1,302 ft; the ground between airports is higher still. Check the sectional chart for the terrain and the minimum safe heights along the line.
At GYY when you get there the forecast at the estimated arrival, 4:25 am CDT (09:25 UTC)
GYY has no terminal forecast; use the nearest airport that does.
Temporary flight restrictions on the line or within 25 nm of it
- 6/5849 Austin, TX, Friday, October 2, 2026 through Monday, October 12, 2026 UTC 5 nm from the route, 60 nm along the route · drones kept away from a public gathering · until 12 October · ZHU
- 6/0543 MCGREGOR, TX 18 nm from the route, 119 nm along the route · security · ZFW
Daylight
Sunset at SAT 7:06 pm CDT (00:06 UTC), at GYY 6:13 pm CDT (23:13 UTC) (civil twilight ends 6:41 pm CDT (23:41 UTC)). At 120 knots the arrival at GYY is before sunrise there (6:58 am CDT (11:58 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
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: San Antonio International, Gary/Chicago International.