Garmin G1000 Pilot's Manual page 223

NEXRAD L
NEXRAD radar images may have certain limitations:
• NEXRAD base reflectivity does not provide sufficient information to determine cloud layers or precipitation
characteristics (wet hail vs. rain). For example, it is not possible to distinguish between wet snow, wet
hail, and rain.
• NEXRAD base reflectivity is sampled at the minimum antenna elevation angle. An individual NEXRAD
site cannot depict high altitude storms at close ranges. It has no information about storms directly over
the site.
• When zoomed in to a range of 30 nm, each square block on the display represents an area of four square
kilometers. The intensity level reflected by each square represents the
sampled within the area (Figure 6-6).
NEXRAD radar images may display abnormalities:
• Ground clutter
• Strobes and spurious radar data
• Sun strobes (when the radar antenna points directly at the sun)
• Interference from buildings or mountains, which may cause shadows
• Metallic dust from military aircraft, which can cause alterations in radar scans
190-00595-00 Rev. A
IMITATIONS
Figure 6-6 NEXRAD Data - Zoomed
Garmin G1000 Pilot's Guide for Beechcraft A36/G36
HAZARD AVOIDANCE
highest
level of NEXRAD data
Block has an Area
of 4 sq. km
6-9