Weather

Question 1

Name four types of weather briefing.

Answer 1

1. Standard briefing
2. Abbreviated briefing
3. Outlook briefing
4. Inflight briefing

Question 2

Describe EFAS

Answer 2

Enroute Flight Advisory Service. Provides weather information to aircraft flying at 5,000’ AGL to 17, 500’ MSL on 122.0 MHz. AKA “Flight Watch”

Question 3

Define HIWAS

Answer 3

Hazardous Inflight Weather Advisory Service (HIWAS) is a continuous broadcast of hazardous weather information which is transmitted over selected VORs/NAVAIDs.

Question 4

What types of weather information may be included in a HIWAS report?

Answer 4

HIWAS weather may include AIRMETs, SIGMETs, Convective SIGMETs, and urgent PIREPs.

Question 5

What are the types of Enroute Inflight Weather Advisories?

Answer 5

The advisories are of three types:

1. Convective SIGMET
2. SIGMET
3. AIRMET

Question 6

What is a Convective SIGMET?

Answer 6

Covers severe convective conditions that may be hazardous to all categories of aircraft.

Question 7

What conditions might be included in a Convective SIGMET?

Answer 7

Conditions may include:

a. severe or greater turbulence,
b. severe thunderstorms,
c. surface winds of 50 kts or greater,
d. hail at the surface of 3/4’ or greater,
e. tornadoes,
f. severe icing, and
g. low-level wind shear.

Question 8

When are AIRMETs issued?

Answer 8

AIRMETs are issued every 6 hours beginning at 0145 UTC

Question 9

Define the term “ceiling.”

Answer 9

The height above the earth’s surface of the lowest layer of clouds or obscuring phenomena that is reported as broken, overcast, obscuration, and not classified as thin or partial.

Question 10

Define the term “broken” as it applies to sky coverage.

Answer 10

Clouds which cover between 6/10 and 9/10 of the sky.

Question 11

From which primary source should information be obtained regarding expected weather at the ETA if your destination has no TAF?

Answer 11

The primary source of preflight weather briefings is an individual briefing obtained from a briefer at the FSS.

Question 12

What conditions are required for thunderstorm development?

Answer 12

Generally, thunderstorms require three conditions to form:

1. Moisture
2. An unstable airmass
3. A lifting force (heat)

Question 13

What are the three stages of thunderstorm development?

Answer 13

All thunderstorms, regardless of type, go through three stages:

1. the developing stage,
2. the mature stage, and
3. the dissipation stage.

Question 14

Name the three types of AIRMETs

Answer 14

AIRMET Sierra, AIRMET Tango, and AIRMET Zulu

Question 15

Describe AIRMET Sierra.

Answer 15

AIRMET Sierra describes IFR conditions and/or extensive mountain obscurations.

Question 16

Describe AIRMET Tango.

Answer 16

AIRMET Tango describes moderate turbulence; sustained surface winds of 30 knots or greater; and non-convective, low-level wind shear.

Question 17

Describe AIRMET Zulu.

Answer 17

AIRMET Zulu describes moderate icing and provides freezing-level heights.