Forecasts Unit 7 Day 5

Science Starter! 1)How do air masses interact at a warm front and what type of weather results? 2)How do air masses interact at a cold front and what type of weather results? 3)Hurricanes and tornadoes are what type of pressure system?

Agenda Warm Up & Objective Wind & Station Model Basics Forecast essentials: Interpreting symbols Paired Weather Stations Activity Weather Forecast Mapping Project Exit Ticket HW: Forecast Write-up

Objective SWBAT Explain and apply knowledge of weather symbols and data provided in maps and diagrams to predict the weather.

Wind Solar Energy = energy source for wind (unequal heating of Earth’s surface generates pressure differences) The Coriolis effect only influences the direction of the wind, not the speed.

Local vs. Global Winds Local: Influenced by topography (shape of land) Global Winds: large currents of winds that transfer heat from the poles and the equator (just like ocean currents!)

Winds Jet streams are fast moving “rivers” of air that flow at high altitudes Centers of low pressure=cyclones Centers of high pressure=anticyclones

Types of Global Winds Trade Winds- Two belts of winds that blow from the east. Westerlies- Belts of wind blowing from the west. **All weather in the US travels west to east** Polar Easterlies- Winds that blow from the polar high toward the subpolar low.

Weather Stations Symbols used to determine several factors including: 1.Temperature 2.Cloud Cover 3.Dew Point 4.Pressure 5.Wind Speed (measured in knots/1 knot=1.15 mph) and Direction

HUMIDITY Humidity is the amount of water vapor in the air. Measured in percentage of total water vapor the air can hold. EX: 75% humidity means the air has 75% of the amount of water vapor it can hold

Wind Speed “Feathers” off the main line represent wind speed Half Feather = 5 mph Full Feather = 10 mph EX: What is the wind speed in Utica, New York? _______ 5 knots 10 knots

ATMOSPHERIC PRESSURE This number is rounded to the nearest 10 th, with the leading 9 or 10 omitted. 1)Add a decimal 2)Add a 9 or 10 in front of the number 3)Determine which is closest to 1000

ATMOSPHERIC PRESSURE or

O Baton Rouge, LA In Baton Rouge, there was no cloud cover. The temperature was 70 degrees, with wind blowing from the south at 5 knots. There was 75 percent humidity with an atmospheric pressure of mb. There was no previous weather. Cloud cover: _____________________Wind direction: ___________________ Wind speed: _____________________Temperature: ____________________ Humidity: _______________________Atmospheric Pressure: _____________ Previous Weather: _______________

H and L 1)locate the observation station with the lowest atmospheric pressure and write the word “Low” just above it. 2)The cold front comes out of the high-pressure center 3)The warm front comes out of the low-pressure center

What weather is this location experiencing? Cloud cover: _____________ Wind direction: ___________________ Wind speed: _____________________ Temperature: ____________________ Humidity: _______________________ Atmospheric Pressure: _____________ Previous Weather: _______________

Weather Station Wind Speed (mph) Wind Direction Atmospheric Pressure (mb) Temperature ( o F)Type of Weather Cloud Coverage (%) Seattle7260 o Phoenix1150 o San Francisco8135 o Fog25 Boston12100 o Fog25 Colorado24225 o o Snow75 Dallas29315 o Hail100 Oklahoma City45315 o Thunderstorms100 Atlanta20120 o Drizzle50

Homework Find a weather map in the newspaper or on the internet. Use your knowledge to write a 1-paragragh description about the weather forecast and the influencing factors (e.g. air fronts, temperature, pressure systems, and wind).

Exit Ticket