Transcript Weather Forecasting and Prediction

Weather Forecasting and
Prediction
Methods of Forecasting
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Step 1 - Outside!
Step 2 - Satellite maps
Step 3 - Radar imagery
Step 4 - Surface and upper air maps
Step 5 - Computer models
Step 6 - Forecast experience/education
Step 1 – What’s Happening Outside
 Cloud Types (High, Middle, Low, Cloud
Cover)
 Sunshine
 Temperature
 Winds (Direction, Speed)
 Dewpoint (How Sticky Is It)
 Precipitation (Rain, Snow, Sleet)
 Lightning and Thunder
High Clouds
 A Sign of Upper Level Moisture,
Precipitation or Storms Possible within 24
Hours
Middle Clouds
 If Seen In Morning with Vertical
Development, Possibility of PM T-storms
Low Clouds
 Usually Little Precipitation (Drizzle, Light
Rain, Snow Shower)
Cumulonimbus – Thunderstorms
Approaching
Local Observations
 Metar Reports
 KLNS 140053Z 02008KT 9SM -RA BKN015 OVC024
14/13 A2984 RMK AO2 RAB50 SLP104 P0000 T01440128
 First the station, then the date and time (Z = GMT), then
the wind direction (first three digits) and speed (last two
digits) and the abbreviation KT for knots. Then the visibility,
in SM (statute miles), the present weather (if any), and the
sky cover. The two numbers separated by a slash are the
temperature and dew point, in Celsius. Then comes the
altimeter setting, in hundredths of an inch of mercury,
preceded by an A. Finally comes the remarks.
Step 2 – Satellite Maps
 We Have Satellites That Orbit Around the
Earth and Take Photos of The Clouds
 There are Several Types of Satellite
Pictures
– Visible (Shows Land, Water, Clouds)
– Water Vapor (Shows Atmospheric Water Vapor)
– Infrared (Bounces Radiation Off Clouds, Can
See Fog and Snow Cover)
Visible Satellite Image
Water Vapor Satellite Image
Infrared Satellite Image
Radar Imagery
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Nexrad (Next Generation Radar)
150+ Doppler Radars
Detects Precipitation
Wind Direction and Velocity
Radar Dish Sends Out Pulse Which
Bounces Off Clouds and Precipitation and
Returns Back to the Dish
Surface and Upper Air Maps
 Shows Features (High Pressure, Low
Pressure)
 Wind Direction and Velocity
 Heights of Pressure Levels
 Temperatures
Computer Models
 Take Mathematical Formulas and
Climatology Data and Predict What Will Be
Going On In the Atmosphere
 Predictions Out to 16 Days, However, Best
Data Within 3-7 Days
 NAM (North American Model)
 GFS (Global Forecast System)
 European, Canadian, + Many More
Forecast Experience/Education
 Know Geography and Climate of the Area
You are Forecasting
 Understand Forecast Model Trends
 Remember the Weather Can Change at Any
Moment without Warning
 Understand the Processes That Occur In
The Atmosphere