Nexrad Intensity - Garmin 400 Series Pilot's Manual Addendum

NEXRAD Intensity

Colors are used to identify the different NEXRAD echo intensities (reflectivity) measured in dBZ
(decibels of Z). "Reflectivity" (designated by the letter Z) is the amount of transmitted power returned to
the radar receiver. The dBZ values increase as returned signal strength increases. Precipitation intensity is
displayed on the 400/500 Series units using colors represented by the dBz values listed in Table 2-1.
Display dBZ Rain
(inches/hour)
GDL 49 GDL 69
<-10 .00"
-10 .00"
-5 .00"
0 .00"
5 .00"
10 0" – trace
15 .01"
20 .02"
25 .05"
30 .09"
35 .24"
40 .48"
45 1.25"
50 2.5"
55 5.7"
60 12.7"
65
70
75
Snow
(inches/hour)
Atmos Cloud Rain
.00"

.00"
 
trace
 
trace - .05"
 
trace - .10"
 
.10" Light
 
.1-.2" Light
.2-.3" Light
.3-.5" Light
.5-.7" Light – Moderate
.7-1.0" Moderate
1"+, or sleet Heavy
1"+, or sleet Heavy
sleet Intense
sleet Extreme
Extreme
Extreme
Table 2-1 NEXRAD Intensity Colors
Remarks
Snow Sleet Hail
Very Light
Light
Light
Light
Light
Light – Medium
Moderate
Heavy

Heavy

Heavy

 
 


Large
Large
Section 2
NEXRAD Overview

The information presented in this Pilot's Guide regarding
NEXRAD is not meant to be comprehensive. The NOAA website
contains complete and detailed information regarding NEXRAD
weather radar operation and theory. You can visit them at
www.noaa.gov.
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