Weather Instruments & Forecasting Weather was studied at particular locations until the invention of surface maps (1800s) & aircraft Weather stations spring up around airports Early 1900s-1960s: weather forecasting based on surface maps Invention of radar & satellites brought whole new dimension to weather forecasting Radar was the first way we could “see” precipitation Satellites were the first way we could “see” storms from outer space

I. Satellite 1. Two types: a. Geostationary - fixed position, can watch a large area 24/7

b. Polar – only take 2 pictures per day (better quality); closer to Earth Geostationary vs. Polar-Orbiting Satellites

2. Two modes: a. Visible (VIS) - what we’d see from space  Pros - very detailed, can spot cloud thickness  Cons – can’t see at night, can’t distinguish snow from clouds easily

2. Two modes: b. Infrared (IR) – measure clouds based on temperature  Pros - c overage day and night, 24/7  Cons - difficult to spot low clouds (i.e. fog)  High clouds are cold and show up brightly on an infrared image  Low clouds are warm and show up darker on an infrared image

II. Doppler Radar – measures precipitation intensity and coverage; wind speed and direction A radar beam shoots a wave of energy out of the tower The wave bounces off particles like precipitation Part of the wave returns to the tower Doppler Radar in Weather Forecasting Doppler Effect Explained

Rain Intensity Red and PurpleHeavy Orange and YellowModerate Green and BluesLight

Type of Precipitation GreenRain BlueSnow PinkFreezing Rain/Sleet WhiteHail

Using wind speed and direction to recognize tornados

BIRDS!