Training the World’s Best Aviators

7 out of 10 Atmosphere & Airmasses,

Pressure & Winds,

Stability and Clouds

7 out of 10 Frontal Weather

7 out of 10 Weather Hazards

7 out of 10 Weather Reports & Forecasts

7 out of 10 Weather Charts

Avn Weather Exam –

Why is weather important?

Weather affects everything we do!

What is weather?The state of the atmosphere with respect

to temperature, moisture content, turbulence, and cloudiness.

• Air temperature

• Humidity

• Clouds

• Precipitation

• Atmospheric Pressure

• Wind

Terminal Learning Objective

ACTION: Plan a flight for weather considerations

CONDITION: Acting as an aviator and given an IFR or VFR flight mission and available weather information.

STANDARD: In accordance with (IAW) Army Regulation (AR) 95-1, and Field Manual (FM) 1-230

Enabling Learning Objective A

ACTION: Identify the composition of the atmosphere and its effects on weather.

CONDITION: Given pertinent information about the atmosphere.

STANDARD: IAW FM 1-230 para 2-1 thru 2-2

78%

NITROGEN

OXYGEN21%

OTHER GASES1%

Dry Air

Natural Air =

Dry air + Condensation Nuclei and Water Vapor

ACTION: The student will identify the layers of the atmosphere, height, and in which layer weather occurs.

CONDITION: Given pertinent information about the atmosphere.

STANDARD: IAW FM 1-230 para 2-3

Enabling Learning Objective B

Layers of Atmosphere

- Troposphere

- Tropopause

- Stratosphere

Stratosphere

ACTION: The student will identify the atmospheric circulation, Coriolis force, and the three-cell theory.

CONDITION: Given pertinent information about the atmosphere.

STANDARD: IAW FM 1-230 para 6-2, 3, 4

Enabling Learning Objective C

Atmospheric circulation begins with uneven heating.

H

H

L L L

Uneven heating from the sun

Atmospheric circulation is modified by…

Uneven heating from the sunCoriolis Force – The apparent force

caused by the unequal speed of rotation of the earth’s surface. This force deflects non-steerable bodies to the right in the Northern Hemisphere.

Atmospheric circulation is modified by…

Uneven heating from the sunCoriolis Force – The apparent force

caused by the unequal speed of rotation of the earth’s surface. This force deflects non-steerable bodies to the right in the Northern Hemisphere.

• Tilt of the earth

Atmospheric circulation is modified by…

H

H

L L LH HHH

HHHHL

L L

L

H

H

L L L

H HHH

L

L L

L

L

L L

HHH H

H

H

L L L

H HHH

L

L L

L

L

L L

HHH H

Global Circulation

Local circulation discussed in future classes

ACTION: The student will identify the four types of heat transfer.

CONDITION: Given pertinent information about heat energy.

STANDARD: IAW FM 1-230 para 3-5

Enabling Learning Objective D

METHODS OF HEAT TRANSFER

• RADIATION

METHODS OF HEAT TRANSFER

• RADIATION• CONDUCTION• CONVECTION

Strongest thermal currents created over landmass during daylight

hours

METHODS OF HEAT TRANSFER

• RADIATION• CONDUCTION• CONVECTION• ADVECTION

Insolation

Terrestrial Radiation

Conduction

InsolationInsolation

Conduction

Convection

AdvectionAdvection

Sea Breeze Effect

Land Breeze Effect

Be back prior to arrival at OZR. (ETA 00+10)

ACTION: The student will identify the relationship of temperature with altitude change, to include temperature inversions.

CONDITION: Given pertinent information about the temperature.

STANDARD: IAW FM 1-230 para 3-7b

Enabling Learning Objective E

A MEASUREMENT OF THE LEVEL OF INTENSITY OF HEAT ENERGY

MEASURED IN DEGREES CELSIUS

Temperature

• Warmest temperatures near ground

• Decreases with altitude

• Standard Lapse Rate

• OLR – Observed Lapse Rate

TEMPERATUREINVERSIONS

WARMER AIR ABOVE COLDER AIR

• NOCTURNAL

• FRONTAL

Best conditions for nocturnal inversion - clear and cool night

Overcast Sky / Greenhouse Effect

prevents a temperature inversion

03o C 05o C0o C

ACTION: The student will identify the characteristics, classification, stability and movement of an air mass.

CONDITION: Given pertinent information about air masses.

STANDARD: IAW FM 1-230 Chapter 9

Enabling Learning Objective F

AIR MASS - A LARGE BODY OF AIR WHOSE PHYSICAL PROPERTIES ARE HORIZONTALLY UNIFORM

TEMP 2° CDP -10° C

TEMP 30° CDP 25° C

North American High

Siberian High

Icelandic High

Bermuda High

Pineapple High

AIR MASSCLASSIFICATION

c = CONTINENTAL AIR MASS

(DRY AIR)

m = MARITIME AIR MASS

(MOIST AIR)

AIR MASSCLASSIFICATION

A = ARCTIC AIR MASS (70° TO 90°)

P = POLAR AIR MASS (40° T0 60°)

T = TROPICAL AIR MASS (10° TO 30°)

E = EQUATORIAL AIR MASS (O° TO 10°)

AIR MASSCLASSIFICATION

cP Continental Polar

Maritime Polar

mT Maritime Tropical warm, moist

cT Continental Tropical warm, dry

cold, moist

cold, dry

mP

Continental Arctic

Equatorial

cA

E

coldest, dry

warmest, moist

AIR MASSSTABILITY

w = Stable

k = Unstable

20°c

35°c

0°c

15°c

Stable air mass: air is warmer than the ground indicated by the symbol - w

AIR MASS CHARACTERISTICS

W TYPE AIR MASS

• STRATUS CLOUDS• FOG• LOW CEILINGS• POOR VISIBILITY• SMOOTH FLYING CONDITIONS• LIGHT OR CALM WINDS• CONTINOUS LIGHT RAIN• USUALLY IFR CONDITIONS

Unstable air mass: air is colder than the ground indicated by the symbol - K

35°c20°c

15°c

0°c

AIR MASS CHARACTERISTICSK TYPE AIR MASS

• CUMULUS CLOUDS• HIGH CEILINGS• GOOD VISIBILITY• TURBULENCE• GUSTY SURFACE WINDS• THUNDERSTORMS, HEAVY RAIN SHOWERS, HAIL, LIGHTNING

Hailstone sizeMeasurement Updraft Speed

in. cm. mph m/s

bb < 1/4 < 0.64 < 24 < 11

pea 1/4 0.64 24 11

marble 1/2 1.3 35 16

dime 7/10 1.8 38 17

penny 3/4 1.9 40 18

nickel 7/8 2.2 46 21

quarter 1 2.5 49 22

half dollar 1 1/4 3.2 54 24

walnut 1 1/2 3.8 60 27

golf ball 1 3/4 4.4 64 29

hen egg 2 5.1 69 31

tennis ball 2 1/2 6.4 77 34

baseball 2 3/4 7.0 81 36

tea cup 3 7.6 84 38

grapefruit 4 10.1 98 44

softball 4 1/2 11.4 103 46

AIR MASSCLASSIFICATION

cPk

mPk Maritime Polar unstable

mTw Maritime Tropical stable

Continental Tropical unstable

Continental Polar unstable

cTk

cPk

cTk

mPk

mTw

ACTION: The student will identify the typical weather associated with air masses.

CONDITION: Given pertinent information about a type of air mass.

STANDARD: IAW FM 1-230 Chapter 9

Enabling Learning Objective G

FM 1-230 References for today

• Atmosphere 2-1 thru 2-3

• Temperature 3-1 thru 3-5

• Atmospheric Circulation 6-1 thru 6-5

• Air Masses 9-1 thru 9-11

FM 1-230 Referencesfor tomorrow…

• Pressure 5-1 thru 5-7

• Atmospheric Circulation 6-6 thru 6-8

Safety First…

“Nothing we do is worth an accident.”

STOPSTOP

Abandon hope all ye who enter hereAbandon hope all ye who enter here

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QUESTIONS

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