Formation
What are the tiny frozen balls that form when supercooled water droplets collide and freeze in a thunderstorm cloud?
Hail/hailstone
What force in a storm keeps hailstones aloft so they can grow larger?
Updraft
They develop a layered look.
If ice forms near the cloud top but melts before reaching the ground, what type of precipitation will the ground observers detect?
Raindrops
Describe what "supercooled" water droplets are.
very, very cold water droplets
According to the table, what approximate updraft speed (in mph) is associated with the size of a golf ball?
64 mph
What causes the clear rings in a layered hailstone?
air molecules can escape from the slowly freezing water drops
Why do some clouds produce rain instead of hail, even though ice forms in the upper parts of the same cloud?
When the ice pieces are too small they start to fall, which causes them to melt before they reach the ground
Explain why thunderstorms with very tall clouds are more likely to produce hail than shallow clouds?
When the clouds grow tall, they lift the water droplets into very cold parts of the atmosphere.
Identify the general pattern in the table that relates hailstone size to updrafts speed. (As _____ increases/decreases then ______ increases/decreases)
As updrafts speed increases then hailstone size increases
What causes the white (opaque) rings in a layered hailstone?
the supercooled water drops freeze instantly, trapping air molecules
Explain how ground temperature influences whether precipitation falls as snow or rain
Snow forms when the temps near the ground are low, close to 32 degrees F.
What causes hailstones to grow?
They are colliding with other water droplets and become bigger as those droplets freeze on them.
Explain why stronger updrafts allow some hailstones to reach sizes like a softball.
When updrafts are stronger, they produce stronger lift forces and therefore can keep hailstones in the cloud longer
Describe how altering growth conditions inside a cloud produce the "layered onion-like" appearance in hailstones
hailstones grow in both of these ways and collide with supercooled and not supercooled water drops, when they go through both types of growth they develop this look
Updrafts are weaker and will not keep snow aloft in the cloud if snowflakes are big, which make them fall back to Earth
Describe start to finish the process of creating a hailstone.
(Water evaporates from the surface), water droplets get supercooled in tall thunderstorm clouds, they collide with other water droplets which freeze onto them
Given the table, describe how you would predict the updraft speed needed to form a hailstone about 3 inches in diameter. Explain your reasoning using the table's pattern
84 mph or 135 km/h, reading the table
Using your whiteboard- Create a sketch of a layered hailstone and explain what changes in a cloud would produce each layer.
check whiteboard
How could the same thunderstorm produce hail in one location but rain in another location?
Must discuss updrafts in answer.