ATP - WEATHER SERVICES

Weather Advisory Broadcasts, including Severe Weather Forecast Alerts (AWW), SIGMETs, and Convective SIGMETs are provided by. ARTCCs on all frequencies, except emergency, when any part of the area described is within 150 miles of the airspace under their jurisdiction. Flight Service on 122.2 MHz and adjacent VORs, when any part of the area described is within 200 miles of the airspace under their jurisdiction. selected low-frequency and/or VOR navigational aids.

The minimum vertical wind shear value critical for probable moderate or greater turbulence is. 4 knots per 1,000 feet. 6 knots per 1,000 feet. 8 knots per 1,000 feet.

What does the contraction VRB in the Terminal Aerodrome Forecast (TAF) mean?. Wind speed is variable throughout the period. Cloud base is variable. Wind direction is variable.

In the following METAR/TAF for HOU, what is the ceiling and visibility forecast on the 7th day of the month at 0600Z? KHOU 061734Z 0618/0718 160014G22KT P6SM VCSH BKN018 BKN035 FM070100 17010KT P6SM BKN015 OVC025 FM070500 17008KT 4SM BR SCT008 OVC012 FM071000 18005KT 3 SM BR OVC007 FM071500 23008KT 5SM BR VCSH SCT008 OVC015. Visibility 6 miles with a broken ceiling at 15,000 feet MSL. 4 nautical miles of visibility and an overcast ceiling at 700 feet MSL. 4 statute miles visibility and an overcast ceiling at 1,200 feet AGL.

The remarks section of the Aviation Routine Weather Report (METAR) contains the following coded information. What does it mean? RMK FZDZB42 WSHFT 30 FROPA. Freezing drizzle with cloud bases below 4,200 feet. Freezing drizzle below 4,200 feet and wind shear. Wind shift at three zero due to frontal passage.

What single reference contains information regarding a volcanic eruption, that is occurring or expected to occur?. In-Flight Weather Advisories. Terminal Area Forecast (TAF). Weather Depiction Chart.

The most current en route and destination weather information for an instrument flight should be obtained from the. Flight service. ATIS broadcast. Notices to Airman publications.

When turbulence causes changes in altitude and/or attitude, but aircraft control remains positive, that should be reported as. light. severe. moderate.

What is the thickness of the cloud layer given a field elevation of 1,500 feet MSL with tops of the overcast at 7,000 feet MSL? METAR KHOB 151250Z 17006KT 4SM OVC010 13/11 A2998. 4,500 feet. 6,500 feet. 5,500 feet.

What is the bottom of the lowest overcast layer in the following pilot report? KMOB UA /OV APE230010/TM 1515/FL085/TP BE20/SK BKN065/WX FV03SM HZ FU/TQ 20/TB LGT. There is not a defined ceiling in this report. There is a layer reported at 8,500 feet. There is a broken layer at 6,500 feet.

Which correctly describes the purpose of convective SIGMETs (WST). They consist of an hourly observation of tornadoes, significant thunderstorm activity, and large hailstone activity. They contain both an observation and a forecast of all thunderstorm and hailstone activity. The forecast is valid for 1 hour only. They consist of either an observation and a forecast or just a forecast for tornadoes, significant thunderstorm activity, or hail greater than or equal to 3/4 inch in diameter.

The Hazardous Inflight Weather Advisory Service (HIWAS) is a broadcast service over selected VORs that provides. SIGMETs and AIRMETs at 15 minutes and 45 minutes past the hour for the first hour after issuance. continuous broadcast of inflight weather advisories. SIGMETs, CONVECTIVE SIGMETs and AIRMETs at 15 minutes and 45 minutes past the hour.

On a Surface Analysis Chart, close spacing of the isobars indicates. weak pressure gradient. strong pressure gradient. strong temperature gradient.

What is the upper Limit of the Low Level Significant Weather Prognostic Chart?. 30,000 feet. 24,000 feet. 18,000 feet.

From which of the following can the observed temperature, wind, and temperature/ dewpoint spread be determined at a specified altitude?. Stability Charts. Winds Aloft Forecasts. Constant Pressure Analysis Charts.

During preflight preparation, weather report forecasts can best be obtained by means of contacting the. weather forecast office (WFD). air route traffic control center. pilot's automatic telephone answering service.

The station originating the following METAR observation has a field elevation of 3,500 feet MSL. If the sky cover is one continuous layer, what is the thickness of the cloud layer? (Top of overcast reported at 7,500 feet MSL). METAR KHOB 151250Z 17006KT 4SM OVC005 13/11 A2998. 2,500 feet. 3,500 feet. 4,000 feet.

What weather phenomenon is implied within an area enclosed by small scalloped lines on a U.S. High-Level Significant Weather Prognostic Chart?. Cirriform clouds, light to moderate turbulence, and icing. Cumulonimbus clouds, icing, and moderate or greater turbulence. Cumuliform or standing lenticular clouds, moderate to severe turbulence, and icing.

What flight planning information can a pilot derive from Constant Pressure Analysis Charts?. Winds and temperatures aloft. Clear air turbulence and icing conditions. Frontal systems and obstructions to vision aloft.

Which chart provides a ready means of locating observed frontal positions and pressure centers?. Surface Analysis Chart. Constant Pressure Analysis Charts. Weather Depiction Chart.

A pilot reporting turbulence that momentarily causes slight, erratic changes in altitude and/or attitude should report it as. light chop. light turbulence. moderate turbulence.

What type of Inflight Weather Advisories provides an en route pilot with information regarding the possibility of moderate icing, moderate turbulence, winds of 30 knots or more at the surface and extensive mountain obscurement?. Convective SIGMET's and SIGMET's. Severe Weather Forecast Alerts (AWW) and SIGMETs. AIRMET's and Center Weather Advisories (CWA).

What is meant by the Special METAR weather observation for KBOI? SPECI KBOI 091854Z 32005KT 1 1/2SM RA BR OVC007 17/16 A2990 RMK RAB12. Rain and fog obscuring two-tenths of the sky; rain began at 1912Z. Rain and mist obstructing visibility; rain began at 1812Z. Rain and overcast at 1200 feet AGL.

SIGMETs are issued as a warning of weather conditions which are hazardous. to all aircraft. particularly to heavy aircraft. particularly to light airplanes.

The U.S. High-Level Significant Weather Prognostic Chart forecasts significant weather for what airspace?. 18,000 feet to 45,000 feet. 24,000 feet to 45,000 feet. 24,000 feet to 63,000 feet.

Which weather chart depicts conditions forecast to exist at a specific time in the future?. Freezing Level Chart. Weather Depiction Chart. 12-Hour Significant Weather Prognostic Chart.

To best determine general forecast weather conditions covering a flight information region, the pilot should refer to. Graphical Forecasts for Aviation (GFA). Weather Depiction Charts. Satellite Maps.

What values are used for Winds Aloft Forecasts?. True direction and MPH. True direction and knots. Magnetic direction and knots.

To best determine observed weather conditions between weather reporting stations, the pilot should refer to. pilot reports. Area Forecasts. prognostic charts.

Dashed lines on a Surface Analysis Chart, if depicted, indicate that the pressure gradient is. weak. strong. unstable.

What is the meaning of the terms PROB40 2102 +TSRA as used in a Terminal Aerodrome Forecasts (TAF)?. Probability of heavy thunderstorms with rain showers below 4000 feet at time 2102. Between 2100Z and 0200Z there is a forty percent (40%) probability of thunderstorms with heavy rain. Beginning at 2102Z forty percent (40%) probability of heavy thunderstorms and rain showers.

What significant cloud coverage is reported by this pilot report? KMOB UA/OV 15NW MOB 1340Z/SK OVC-TOP025 / OVC045-TOP090. Three (3) separate overcast layers exist with bases at 250, 7,500 and 9,000 feet. The top of the lower overcast is 2,500 feet; base and top of second overcast layer is 4,500 and 9,000 feet, respectively. The base of the second overcast layer is 2,500 feet; top of second overcast layer is 7,500 feet; base of third layer is 9,000 feet.

Which statement pertaining to the following Terminal Aerodrome Forecast (TAF) is true? TAF KMEM 091135Z 0915 15005KT 5SM HZ BKN060 FM1600 VRB04KT P6SM SKC. Wind in the valid period implies surface winds are forecast to be greater than 5 KTS. Wind direction is from 160º at 4 KTS and reported visibility is 6 statute miles. SKC in the valid period indicates no significant weather and sky clear.

The difference found by subtracting the temperature of a parcel of air theoretically lifted from the surface to 500 millibars and the existing temperature at 500 millibars is called the. lifted index. negative index. positive index.

Terminal Aerodrome Forecasts (TAF) are issued how many times a day and cover what period of time?. Four times daily and are usually valid for a 24 hour period. Six times daily and are usually valid for a 24 hour period including a 4-hour categorical outlook. Four times daily and are valid for 12 hours including a 6-hour categorical outlook.

Hatching on a Constant Pressure Analysis Chart indicates. hurricane eye. windspeed 70 knots to 110 knots. windspeed 110 knots to 150 knots.

The Surface Analysis Chart depicts. frontal locations and expected movement, pressure centers, cloud coverage, and obstructions to vision at the time of chart transmission. actual frontal positions, pressure patterns, temperature, dewpoint, wind, weather, and obstructions to vision at the valid time of the chart. actual pressure distribution, frontal systems, cloud heights and coverage, temperature, dewpoint, and wind at the time shown on the chart.

What wind conditions would you anticipate when squalls are reported at your destination?. Rapid variations in windspeed of 15 knots or more between peaks and lulls. Peak gusts of at least 35 knots combined with a change in wind direction of 30º or more. Sudden increases in windspeed of at least 16 knots to a sustained speed of 22 knots or more for at least 1 minute.

Turbulence that is encountered above 15,000 feet AGL not associated with cumuliform cloudiness, including thunderstorms, should be reported as. severe turbulence. clear air turbulence. convective turbulence.

On a Surface Analysis Chart, the solid lines that depict sea level pressure patterns are called. isobars. isogons. millibars.