“It’s a warm front,” Maya said, running the mental checklist. “Pressure has dropped 4 hPa in the last three hours. Wind has veered from 160 to 210. That’s classic warm front advection. But Captain, the METAR is reporting visibility 800 meters in freezing drizzle, ceiling indefinite… they’re calling it vertical visibility 100 feet .”
Jim pointed to a tiny symbol on the weather radar overlay: a purple triangle. “That’s not just rain. That’s hail aloft. And in a warm front with divergence aloft, the convection can build faster than the radar update. I’ve seen it before.”
“Because the anvil from that cell is spreading downwind—right over Rome’s ILS localizer. That means low-level wind shear and possible microbursts on the go-around. We don’t have the fuel to play guessing games.” meteorology atpl questions
“Drinks are on me,” Jim said, unstrapping his harness. “But first: what’s the definition of a warm occlusion, and how does it differ from a cold occlusion?”
“Standard lapse rate is 1.98°C per 1,000 feet, but this airmass is stable—temperature drops about 2°C per thousand. From +2°C to 0°C is a 2°C drop. So the freezing level is at 1,000 feet AGL,” Maya calculated. “But the cloud base is 200 feet. The entire layer from 200 to 1,000 is below freezing but above the surface. That’s the sweet spot for severe icing.” “It’s a warm front,” Maya said, running the
Jim was quiet for ten seconds. The radar was now painting a solid line of red across the final approach fix. The GPWS callout chimed softly: “ALTITUDE… ALTITUDE.”
“But here’s the kicker,” Jim said, pointing to the satellite imagery overlay. “Look at the 300 hPa chart. The jet stream core is 150 knots, and we’re on the left exit sector. What does that give us?” That’s classic warm front advection
ATPL Meteorology Question 4: Given a surface temperature of +2°C and a lapse rate of 2°C per 1,000 feet, what is the approximate freezing level?