The first picture (click on pics to enlarge) is of the two storms sitting along our route of flight last month. Up front when it is clear and the thunderstorms are isolated (out in the open for all to see), we can just visually deviate around them as we fly along. We use a radar image to verify what we are seeing with our eyes and to better judge distance of the hazard ahead. When the storms are embedded inside clouds or other storm fronts we must rely on radar to be our eyes in the weather.
The screen shows a "God's Eye" view as if you were looking from space down on the earth. The triangle at the bottom represents our airplane (right at the tip of the triangle) and the line in front of the plane is the track across the earth we will fly (073 degrees or northeast) . The top of the screen has the headings with 9 being 090 degrees or due east. KFSM is Fort Smith, AR and KSGF is Springfield, MO. Simple huh?
The pink line running to the right of our jet represents our original flight path that the autopilot was flying. Notice about 35-40 miles ahead of us on that heading was a big blotch of weather--the same two thunderstorms depicted in the previous picture above. Without deviating, we would have encounterd a thunderstorm cell.
The green indicates rain, with yellow indicating heavier rain, while red indicates intense rain showers and possible ice. We avoid red at all costs at flight level.
In this case, we simply asked Air Traffic Control to deviate north of our route to get around the weather, and once clear of the weather, we were cleared to fly direct to the start of the arrival for our destination. In the lower left of the radar picture you can barely make out 258/87. That is the jetstream wind blowing from the west (258 degrees) at 87 knots. Downwind of the thunderstorms, the ride got a little choppy due to the turbulence of the fast jet bubbling around the tall thunderstorms. We were at 41,000 feet, and the thunderstorms extended way above us.
See how simple this is? Reee-laaaax!!!!
Captain Ray Stark