曝光台 注意防骗
网曝天猫店富美金盛家居专营店坑蒙拐骗欺诈消费者
determine where they can find lift and how long the lift
will be usable for soaring flight.
GRAPHIC WEATHER CHARTS
Reports of observed weather are graphically depicted
in a number of weather products. Among them are the
surface analysis chart, weather depiction chart, radar
summary chart, and composite moisture stability chart.
SURFACE ANALYSIS CHART
A surface analysis chart is a computer-generated
graphic that covers the 48 contiguous states and adjacent
areas, for the valid time shown on the chart. The
chart is prepared and disseminated every 3 hours by
human observers.
A review of this chart provides a picture of the atmospheric
pressure patterns at the earth’s surface. [Figure
9-35] In addition, the chart depicts the amount of sky
cover, the velocity and direction of the wind, the temperature,
humidity, dewpoint, and other important
weather data at specific locations. The observations
from these locations are plotted on the chart to aid in
analyzing and interpreting the surface weather features.
[Figure 9-36, on next page.]
WEATHER DEPICTION CHART
The weather depiction chart provides an overview of
favorable and adverse weather conditions for the chart
time and is an excellent resource to help determine
general weather conditions during flight planning.
Information plotted on this chart is derived from aviation
routine weather reports (METARs). Like the surface
chart, the weather depiction chart is prepared and
transmitted by computer every 3 hours and is valid at
the time the data is plotted.
On this chart, a simplified station model is used to
depict the type of weather, amount of sky cover, the
height of the cloud base or ceiling, obstructions to
vision, and visibility. Unlike the station model on a surface
analysis chart, a bracket symbol is placed to the
right of the circle to indicate an observation made by
High Pressure Center
Low Pressure Center
Cold Front
Warm Front
Stationary Front
Occluded Front
Squall Line
Trough
Ridge
SYMBOL DESCRIPTION
Figure 9-35. Surface Analysis Chart.
9-28
an automated system only. [Figure 9-37] The observed
ceiling and visibility for a general area is shown for
IFR, MVFR, and VFR.
IFR—Ceilings less than 1,00 feet and/or visibility less
than 3 miles are depicted in the hatched area outlined
by a smooth line.
MVFR (Marginal VFR)—Ceiling 1,000 to 3,000 feet
and/or visibility 3 to 5 miles is depicted in a nonhatched
area outlined by a smooth line.
VFR—No ceiling or ceiling greater than 3,000 feet and
visibility greater than 5 miles are not outlined.
RADAR SUMMARY CHART
The computer-generated radar summary chart is
produced 35 minutes past each hour and depicts a
collection of radar weather reports (SDs). This
chart displays areas and type of precipitation,
intensity, coverage, echo top, and cell movement.
In addition, an area of severe weather is plotted if they
are in effect when the chart is valid. [Figure 9-38]
U.S. LOW-LEVEL SIGNIFICANT WEATHER
PROGNOSTICATION CHART
The low-level significant weather prognostic chart is
divided into two forecast periods. The two panels on
the left show the weather prognosis for a 12-hour
period and those on the right for a 24-hour period. The
valid times and titles for each panel are shown in the
lower left corner of the respective panel.
The two upper panels depict cloud cover, altitudes of
the freezing level, and areas where turbulence can be
expected. The two lower panels depict the forecasters
best estimate of the location of frontal and pressure systems,
as well as the areas and types of precipitation. It
Figure 9-36. Station Model and Explanation.
Missing
or Partial
Obscuration
Breaks
in
Overcast
PRECIPITATION
The precipitation over the last 6-
hour period is given to the nearest
hundredths of an inch. In the
example, 0.45 inch of precipitation
has fallen in the last 6 hours.
STATION IDENTIFIER
The station identifier is shown to the lower left
of the station model. This observation is from
KABI, or Abilene Regional Airport.
PRESSURE CHANGE/TENDENCY
The pressure change in tenths of
millibars over the past 3 hours is shown
below the sea level pressure. The
tendency of pressure change is depicted
using a symbol to the right of the change.
In the example, pressure has increased
2.8 mb (hPa) over the past 3 hours, and
is increasing more slowly or holding
steady. Other symbols may be decoded
中国航空网 www.aero.cn
航空翻译 www.aviation.cn
本文链接地址：
Glider Flying Handbook(125)
