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23
last
noticeable
change
in
the
weather
was
when
it
was
sunny
(the
sun
icon
only).
Therefore,
the
next
change
in
the
weather
will
be
cloud
with
rain
icons
since
the
indicator
is
pointing
downwards.
Note:
Once
the
weather
tendency
indicator
has
registered
a
change
in
air
pressure,
either
the
upward
or
downward
tendency
arrow
will
be
displayed
until
the
tendency
changes
again.
AIR
PRESSURE
HISTORY
GRAPH
The
LCD
shows
the
relative
air
pressure
value
and
the
air
pressure
history
on
a
bar
graph.
Press
the
SET
key
to
toggle
between
Mode1
and
Mode2
of
the
display.
Mode
1
:
The
bar
graph
displays
the
air
pressure
history
of
the
past
24
hours
in
seven
steps.
The
horizontal
axis
represents
the
last
24
hours
of
air
pressure
recording
(
‐
24,
‐
18,
‐
12,
‐
8,
‐
6,
‐
3
and
0
hour).
Mode
2
:
The
bar
graph
displays
the
air
pressure
history
of
the
past
72
hours
in
seven
steps.
The
horizontal
axis
represents
the
last
72
hours
of
air
pressure
recording
(
‐
72,
‐
48,
‐
36,
‐
24,
‐
12,
‐
6
and
0
hour).
The
vertical
bars
are
plotted
at
each
of
the
seven
steps
and
give
the
trend
over
the
recorded
period.
The
0
hour
vertical
bar
will
always
display
at
the
midline
height
to
indicate
the
current
air
pressure.
The
varying
height
of
bars
in
other
columns
on
the
graph
indicate
a
relative
change
in
air
pressure
up
or
down
from
the
previous
measurement.
New
pressure
measurements
are
compared
to
previously
recorded
pressure
measurements.
The
pressure
change
is
expressed
by
the
difference
between
the
current
("0h")
and
the
past
readings
in
divisions
of
±0.06
inHg
or
±2
hPa.
If
the
bars
are
rising
from
left
to
right,
this
indicates
that
the
weather
is
getting
better
due
to
an
increase
in
air
pressure.
If
the
bars
are
falling
from
left
to
right,
this
indicates
that
the
weather
is
expected
to
get
worse
due
to
a
drop
in
air
pressure.
At
every
full
hour,
the
current
air
pressure
is
used
as
a
basis
for
the
display
of
a
new
graph
bar.
The
existing
graph
is
then
moved
one
column
to
the
left.
Note:
For
accurate
barometric
pressure
trend,
the
Weather
Center
should
operate
at
the
same
altitude.
Should
the
unit
be
moved,
for
instance
from
the
ground
to
the
second
floor
of
the
house,
the
readings
for
the
next
48
‐
60
hours
shall
be
discarded.
Note:
The
bar
graph
will
scroll
right
to
left
regularly
to
prevent
LCD
burnout.
WIND
DIRECTION
AND
WIND
SPEED
MEASUREMENT
A
pointer
on
the
outer
circle
of
the
compass
indicates
the
current
wind
direction.
The
last
6
wind
directions
are
displayed
with
pointers
on
the
inner
circle.
The
wind
direction
(abbreviation
or
degrees)
is
displayed
in
center
of
compass.