Graphic Weather Flashcards
Define weather watch
Severe weather is POSSIBLE during specified time
Define weather warning
Severe weather has been observed (happening now) or is EXPECTED within the hour
How often is a Surface Anaylsis Chart for Aviation Interests transmitted and how long is it valid?
Surface analysis charts are transmitted every 3 hours. The valid time corresponds to the time of the observations
Aviation surface analysis charts will contain what information?
Sky condition, surface wind directions and speed, temperature (℉), surface weather condition, visibiliy, and ceiling
How are tornado warnings depicted/overlaid on radar imagery?
Red polygons
How are severe thunderstorm warnings depicted/overlaid on radar imagery?
Yellow polygons
What is a radar mosaic?
A radar moscaic consists of multiple single-site radar images combined to produce a radar image on a regional or national scale
What is an outflow boundary?
Boundary separating thunderstorm-cooled air from the surrounding air. This can trigger additional weather phenomena.
Solid lines depicting the sea-level pressure patterns are called _____.
Isobars
What are the six pieces of information shown on an aviation surface analysis chart plot?
- Sky condition
- Surface wind direction and speed
- Temperature (℉)
- Surface weather conditions
- Visibility
- Ceiling
Visibilities less than 1 SM are coded _____ on surface analysis charts since fractions are not coded on this chart.
0
Surface analysis charts provide ready means of locating _____ and _____.
Pressure systems and fronts
Radar echoes indicate the _____ of the precipitation
Intensity
Convective precipitation echoes tend to form as _____ or _____.
Cells or Lines
A _____ is used to identify an aircraft reporting position on a Constrant Pressure Analysis chart.
Square
◻︎
A _____ is used to identify a satellite reporting position on a Constant Pressure Analysis chart
Star
☆
Isotachs are drawn at _____ knot intervals and begins at 10 knots
20
300MB is roughly equivalent to _____ feet and _____ meters
30,000 feet and 9,000 meters
Large negative lifted index values of _____ would indicate very unstable air
-6 or less
The KI value is an indicator of the _____ and coverage of storms.
Probability
What does a green area represent on a Short-Range Surface Prog?
Rain
If snow is likely, what is the percentage of probability?
≥ 55%
What are the four intensities of precipitation given by ATC?
Light, moderate, heavy, extreme
What hazards are associated with stratiform precipitation?
Possible widespread icing above the freezing level, low ceilings, reduced visibilities.
Widespread aerial coverage on the radar, echo patterns change slowly
What hazards are associated with convective precipitation?
Turbulence, LLWS, gusty surface winds, icing above the freezing level, hail, tornadoes, localized IFR conditions.
Echoes form as cells or lines, patterns change rapidly
What data is plotted on Constant Pressure Analysis charts?
- Temperature
- Temperature/Dew Point Spread
- Wind
- Height of the surface above sea level
- Height change of the surface over previous 12-hr period
What does a shaded circle mean on a Constant Pressure Analysis chart?
The spread is 5℃ or less
What does a high positive KI imply?
Moist and unstable air
What is an Upper Air Sounding?
A weather report issued twice daily to compute the lifted index and K index.
What are the two projections for Winds and Temperature Aloft Charts?
Mercator (true north is always up, greater distortion at the poles) and Polar (very little distance distortion)
What do G-Airmets provide?
Precise, interactive, easy to understand graphical displays for moderate weather that are issued every 6 hours.
What are prognostic charts?
FORECASTS
What does a green area represent on a prog chart?
Rain
What does a blue area represent on a prog chart?
Snow
What does a purple area represent on a prog chart?
Mix
What does orange represent on a prog chart?
Ice
What does a red area represent on a prog chart?
Striped, chance thunderstorms
Solid, likely thunderstorms
Information is provided for what altitudes on a low-level significant weather prog?
Surface to FL240 (400mb)
Solid lines on a low-level prog enclose areas of _____.
IFR weather
Scalloped lines on a low-level prog chart enclose areas of _____.
MVFR weather
Freezing levels aloft on a low-level prog chart are depicted by _____.
Thin, short, dashed lines
Bold, dashed long lines enclose areas of _____ on a low-level prog chart
Moderate or greater turbulence
How is the freezing level at the surface depicted on a low-level prog chart?
Zigzag lines
When is a mid-level prog chart used?
10,000’ MSL to FL450. Generally used for planning over the North Atlantic
The base of the high-level prog chart is _____ and the top is _____.
FL250, FL630
What is Isolated (ISOL) CB coverage?
Less than 4/8
What is Occasional (OCNL) CB coverage?
4/8-6/8
What is Frequent (FRQ) CB coverage?
More than 6/8
What do 5-sided polygons indicate on high-level progs?
High and low TROP heights
How many times are Convective Outlook Charts issued?
5 times daily
What are the five categories of risk of severe weather the convective outlook defines?
- Marginal risk (MRGL)
- Slight risk (SLGT)
- Enhanced risk (ENH)
- Moderate risk (MDT)
- High risk (HIGH)
Decode
Rain Showers
Decode
Freezing Drizzle
Decode
Mist
Decode
Fog
Decode
Smoke
Decode
Severe Icing
Decode
Moderate Icing
Decode
Tropical thunderstorm. If filled in, hurricane/typhoon
Decode
Volcanic eruption
Decode
Wind from the north west at 75 knots
Decode
Missing cloud (sky cover) observation or partial obscuration
Decode
Sky obscured
Decode
Overcast (> 7/8)
Decode
Breaks in overcast
Decode
Broken (5/8-7/8)
Decode
Scattered (3/8-4/8)
Decode
Few (<1/8-2/8)
Decode
Sky clear
Decode
Thunderstorms with rain
Decode
Freezing rain
Decode
Thunderstorms with snow
Decode
Ice pellets
Decode
Snow pellets
Decode
Drifting snow
Decode
Moderate turbulence
Decode
Extreme turbulence
Decode
Severe turbulence
Decode
Haze
Decode
Sand storm/dust storm
What chart would you find this on?
High level prog chart
Sample radiosonde plot
Sample radiosonde plot
Sample radiosonde plot
Sample radiosonde plot
Sample aircraft plot
Sample aircraft plot
Sample satellite plot
Sample satellite plot
On what chart would you find this and how would you decode it?
High level prog chart.
Occasional embedded CBs at FL520, bottom below chart level. Isolated embedded CBs at FL490, bottoms below chart level
Decode
Snow showers
Sample surface analysis plot
Sample surface analysis plot
How often is data colleted from radiosondes to prepare constant pressure charts?
Twice a day
How often is a surface analysis chart transmitted?
Every 3 hours
Isotherms are depicted as _____ dashed lines.
Bold
Isotachs are depicted as _____ dashed lines
Short, fine
Hatched and unhatched areas are alternated at _____ intervals beginning at 70 knots
40 knot intervals
Upper air soundings are updated every ______.
12 hours
How often are FBs published?
Four times daily
Short-range surface progs are issued ____ daily
4 times daily
Low-level significant weather prog are issued _____ daily
4 times daily
What does the solid line represent?
IFR weather
What does the scalloped line represent?
MVFR weather
What is the difference between the zigzag lines and the thin, short, dashed lines?
The zigzag line is the surface freezing level
The thin, short dashed lines are freezing levels aloft
What do the bold, dashed, brown lines represent?
Moderate or greater turbulence
What altitudes are represented on the low level significant weatehr chart?
Surface - 24,000
How often are high-level significant weather progs issued?
4 times daily
