Relative Humidity/Dewpoint
Water Cycle
Fronts and Air Masses
Air Pressure and Wind
Station Models
100

What is the dewpoint when the dry-bulb temp is 12 C and the wer-bulb temp is 7?

1 C

100

precipitation ------> runoff -------> ocean---------> ??????? --------> water vapor

evaporation

100

What two characteristics are air masses identified by?

temperature and moisture content (humidity)

100

Wind moves from _________ to __________.

High to Low Pressure.

100

How is anemometer data displayed on a station model?

With feathers.  One full feather means 10 knots, a 1/2 is 5 knots.

200

A parcel of air has a dry-bulb temperature reading of 16 C and a wet-bulb temperature reading of 13 C.  What is the relative humidity?

11%

200

Which is a form of precipitation?

A) frost   B) hail    C) fog   D) dew

Hail

200

What symbol (letters) would be used to identify an air mass originating over the Gulf of Mexico?

mT

200

wind at this location?

From the Northeast at 25 knots.

300

A student used a sling psychrometer to measure the humidity of the air.  If they relative humidity was 65% and the dry-bulb temp was 10 C, what was the wet-bulb temp?

7 C

300

When do clouds form?

When warm, wet air rises, expands, cools and the water inside it condenses at the dewpoint.

300

What type of frontal boundary exists when more dense cold air advances under less dense warm air?

cold front

300

As temperature goes up, air pressure?

decreases

400

Which weather instrument is most useful in measuring relative humidity?

Psychrometer

400

What is the process called when plant life puts water vapor into the atmosphere?

transpiration
400

What is the term to describe where an air mass gets its characteristics?

source region

500

Looking at a station model, how can you tell that relative humidity is at 100%?  How can you tell when relative humidity is low?

When temperature and dewpoint are the same, relative humidity is high.  When temperature and dewpoint are far apart, relative humidity is low.

500

Why is is possible for no rain to be falling from a cloud?

The water droplets are too small to fall.

500

Why do clouds usually form at the leading edge of a cold air mass?

Cold air flows under warm air, causing the warm air to rise and cool.