Module 05: Hail & wind estimation

Wet growth, dry growth, and the updraft that has to hold a stone up long enough to build it. Plus the two pieces of hail folklore worth unlearning first. (30 min)

What counts as severe, what to measure, and which reference objects the NWS asks you not to use. (25 min)

Reports under-measure, the archive has a seam in it, and the radar product everyone checks against was built to over-forecast on purpose. (30 min)

Where damaging straight-line wind comes from, the size that separates a microburst from a macroburst, and which of the two your own air mass hands you. Which is the wet kind. (30 min)

The severe threshold, the NWS estimation chart in full, and the well-documented reason a number you guessed is worth less than a sentence describing what moved. (30 min)

What fell, which way it fell, and why the same fallen tree means two different wind speeds depending on the ground it stood in. (25 min)

The shortest lesson in the module, and the one where being wrong costs the most. (20 min)

Two numbers, the freezing level and the boundary-layer moisture, decide which of these two hazards your region actually hands you. They are not the same everywhere, and the training photographs are from somewhere else. (25 min)