SWATC Unit 7

At a minimum, the CWW (Cooperative Weather Watch) documents provide:

• Procedures for ATCT to report changes in tower prevailing visibility when less than 4SM and differs from prevailing surface visibility by at least on reportable value

• Procedures for task-certified ATC personnel to relay PIREPs as soon as practical

What certification will tower controllers obtain from weather personnel?

AF Form 3622, ATC/Weather Certification and Rating Record

Weather personnel will evaluate ____________________ upon receipt of ____________________ that differs from the latest reported surface visibility.

prevailing visibility as soon as practical, tower visibility

Tower personnel are required to notify the weather station when they observe:

• Increasing or decreasing visibility and/or ceiling

• Thunderstorms and other related phenomena

• Precipitation beginning and ending

• Location/movements of fog banks

What are the two types of clouds?

Stratus and Cumulus

Clouds formed by the cooling of a stable layer of air and characterized by their uniform, sheet-like appearance.

Stratus

Clouds formed by vertical currents of unstable air and characterized by their lumpy, billowy appearance.

Cumulus

The prefix __________ or the suffix __________ meaning “__________” is added to the name of precipitation producing clouds.

Nimbo, Nimbus, Rain Cloud

Low Clouds bases range from __________ to __________. Clouds forming __________ and extending to the surface are classified as fog.

SFC, 6,500 feet AGL, below 50 feet

Look like dirty cotton balls. These clouds are formed from the breaking up of stratus layer and from the spreading out of cumulus clouds.

Stratocumulus

Relatively flat bases, dome-shaped tops, and a cauliflower appearance.

Cumulus

Middle Clouds bases range from about __________ to about __________.

6,500 feet, 20,000 feet AGL

Appear as relatively uniform gray to blue sheet covering the entire sky. Light precipitation usually will form in lower of these types of clouds.

Altostratus

White or gray patches of solid cloud. Can be composed of both water and ice crystals of varying compositions.

Altocumulus

Dark, dense, and threatening clouds.

Nimbostratus

High Clouds bases range from about __________ to __________ in mid-latitudes but may be as high as __________ in the tropics.

16,000 feet, 45,000 feet AGL, 60,000 feet AGL

Thin, feathery clouds in patches or narrow bands, often extend from the upper part of thunderstorms or cumulonimbus clouds in what is known as the cirrus anvil.

Cirrus

Thin, whitish layers appearing as a sheet or veil. These clouds occur only in stable layers and produce little to no turbulence.

Cirrostratus

Thin, closely spaced, individual elements, appearing as small cotton balls, indicate instability and can precede thunderstorms by up to 12 hours. Aircraft may experience some turbulence.

Cirrocumulus

Transition cloud between fair weather cumulus and the eventual cumulonimbus cloud, signals changes in atmosphere from stable to unstable. The rapidly growing towering cumulus clouds indicate thunderstorms are probable within minutes. Usually accompanied by turbulence and icing.

Towering Cumulus

Large, dense, towering clouds with cauliflower-like tops.

Cumulonimbus and Towering Cumulonimbus

One of the most unexpected aviation hazards to fly through, and one of the most difficult to forecast as it is caused by abrupt, small-scale variations in wind speed and direction.

Turbulence

Reporting intensities for turbulence.

• Light

• Moderate

• Severe

• Extreme

Ways in which severe/extreme turbulence can compromise aircrew performance.

• Delays Decision Time

• Produces involuntary control movements which may not be obvious to aircrew

• Produces sensory illusion

• Makes reading instruments/displays difficult

To avoid the effects of turbulence, aircrews may request to

climb above turbulent conditions or decrease speed

Deviations in the magnitude and/or direction of adjacent wind is

windshear

__________ are the most hazardous form of windshear due to their small size and rapidly changing wind pattern over short distances which result in extreme windshear.

Microbursts

Weather phenomenon such as thunderstorms and microbursts may produce a change in wind speed and/or direction known as ____________________ which has a tearing or shearing effect on aircraft.

Low Level Windshear (LLWS)

LLWS occurs at all altitudes but is particularly hazardous when it happens on

approach and departure within 2,000 feet AGL

Severe LLWS causes airspeed changes greater than __________ or vertical speed changes greater than __________ per minute.

15 knots, 500 feet

What are the types of icing?

• Clear

• Rime

• Mixed

What are the intensities to report icing?

• Trace

• Light

• Moderate

• Severe

To reduce the effects of icing, pilots may request

a heading or altitude change

A surface-based cloud that is composed of either water droplets or ice crystals and is formed when there is a small temperature dew point spread of 5° F or less

Fog

The most common forms of precipitation that restrict visibility are

• Snow

• Blowing Snow

• Drizzle

• Rain

Contains the most severe weather hazards to flight

Thunderstorms

The leading cause of reportable weather-related aircraft accidents in the Air Force

Lightning strikes and electrostatic discharges

Rotating column of air that touches the ground

Tornado

Rotating column of air that DOES NOT touch the ground

Funnel Cloud

Rotating column of air over water

Waterspouts

Types of hazardous weather advisories:

• Convective SIGMENT (WST)

• Significant Meteorological Information (SIGMET)

A __________ advisory is issued when weather conditions such as severance and extreme turbulence, severe icing, and widespread dust or sandstorms that reduce visibility to less than 3 miles are encountered.

SIGMET

A __________ is an advisory concerning convective weather such as tornadoes, thunderstorms, and hail that is ¾ inch or greater in size.

Convective SIGMENT (WST)

The prevailing visibility that is determined from the normal point of observation (6 feet).

Surface Visibility

The prevailing visibility that is determined from the control tower.

Tower Visibility

Values must represent at least 45° portion of the horizon circle

Sector Visibility

The greatest visibility that is equaled or exceeded throughout half (180°) or more of the horizon.

Prevailing Visibility

Tool used to determine the visibility on specified directions

Visibility Checkpoint Chart

Each visibility marker on the check point chart will include the ____________________ from the point of observation.

distance and direction

When tower visibility is less than 3 miles, it will be reported in

fractions or whole SM and fractions

When tower visibility is 3 to 15 miles, it will be reported in

1 SM increment to the nearest whole mile

When tower visibility is more than 15 miles, it will be reported in

the nearest 5 SM increment

PIREPs are requested when the following conditions exists or is forecast in your area of jurisdiction:

• Ceilings at or below 5,000 feet

• Visibility at or less than 5 miles

• Thunderstorms and related phenomena

• Turbulence of moderate degree or greater

• Icing of light degree or greater

• Windshear

• Volcanic Ash Clouds

• Breaking action reports less than good

• Detection of sulfur gases

What items will be recorded with PIREPs?

• Time

• Type of Aircraft

• Altitude

• Position of Aircraft

When the PIREP involves icing include __________, __________, and the __________ in which icing is occurring.

icing type, intensity, air temperature

Relay all operationally significant PIREPs to:

• Appropriate intrafacility positions

• Other concerned terminal or enroute ATC facilities including non-FAA facilities

• Weather personnel in accordance with Cooperative Weather Watch program

Continually sense and measure the atmosphere at the station and are monitored by USAF weather reporting stations.

Automated Weather Observing System (AWOS)

What information must be available at all controller operating positions?

• Current weather observations

• Pertinent severe weather warnings

• Advisories

• Pilot Reports (PIREPs)

What does AFAS stand for?

Airfield Automation System

AFAS will include a real time

Wind indicator

What information is required to be visible from every page?

• ATIS Code

• Runway in use

• Wind direction and velocity/speed

• Current altimeter setting

Where must all AFAS pages link back to for instant access to current weather/airfield information?

Home page

What must each AFAS be equipped with to suit operational needs?

Visual and aural alarm system

(T/F) General weather that does not include specific values, may be transmitted to pilots without consulting the weather reporting station.

True

(T/F) Specific values, such as ceiling and visibility, may be transmitted if the weather report was composed or verified by the weather station.

True

Tower and weather station differences must be reported to the official weather observer for the element concerned.

True

Each facility has the ability to maintain their own information in AFAS, such as:

• Checklists

• Recall rosters

• Phone numbers

The meteorological data in all __________ reports is occurring at the station at the time of the observation/report.

METAR

Sections of the METAR

Body and Remarks.

Aviation Selected Special Report (SPECI)

An unscheduled observation completed when special criteria are observed or sensed.

Aviation Selected Local Weather Report (LOCAL)

An unscheduled observation not meeting SPECI criteria. LOCALs are only taken when unit leadership determines there is a requirement in support of local operations.

Aviation Routine Weather Report (METAR)

A routine scheduled observation as well as the primary observation code used to satisfy requirements for reporting surface meteorological data.

KCYN is spoken

Canyon

4-digit time followed by the word __________ to indicate UTC time

Zulu

Wind is indicated by the

3-digit direction and 2-digit velocity speed

Wind annotations of 00000KT are spoken as

Wind Calm

The letter “G“ between two wind speed values is pronounced as

Gusts

Visibility is indicated with the reportable value followed by

SM

When the RVR indicated values are separated by a V, preface the values with

variable

RVR “less than” will be indicated by an

M

RVR “more than” will be indicated by a

P

SKC is spoken as

Sky Clear

FEW is spoken as

Few clouds at (height)

SCT is spoken as

(height) scattered

The lowest cloud layer prefixed with the contraction ______________________________ designates the ceiling

BKN or OVC

The temperature and dewpoint are separated by a __________ in the METAR

slash

The altimeter setting is prefixed by an

A

The altimeter setting is followed by

four digits

Generally used to elaborate on parameters reported in the body of the METAR report

Remarks