Transcript Forecasts

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
10 knots
EX: What is the wind
speed in Utica, New York?
_______
5 knots
ATMOSPHERIC PRESSURE
This number is
rounded to the
nearest 10th, 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
138
13.8
1013.8
913.8
or
1013.8
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 998.4 mb. There was
no previous weather.
Cloud cover: _____________________
___________________
Wind speed: _____________________
____________________
Humidity: _______________________
_____________
Previous Weather: _______________
Wind direction:
Temperature:
Atmospheric Pressure:
O
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 (oF) Type of Weather
Cloud
Coverage (%)
Seattle
Phoenix
San Francisco
Boston
Colorado
Dallas
Oklahoma City
7
11
8
12
24
29
45
260o
50o
135o
100o
225o
315o
315o
1020.8
1021.1
1020.0
1018.1
980
1007.8
1007.8
42
45
48
52
30o
60
57
Fog
Fog
Snow
Hail
Thunderstorms
0
0
25
25
75
100
100
Atlanta
20
120o
1032.3
56
Drizzle
50
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