Below is a list and explanation of radar reflectivity pitfalls: 1. Earth's curvature- The Earth's curvature causes more of a storm to be unsampled the further the storm is from the radar site. This makes it more difficult to detect accurate VIL values and mesocyclonic circulations at long ranges from the radar. 2. Topography- Elevated terrain can increase ground clutter and anomalous propagation. Valley regions are not sampled if the radar is on the other side of elevated terrain. 3. Unusual temperature gradients- Strong inversions and other strong temperature lapse rates will refract the radar beam atypically. This will result in echo height errors, can increase ground clutter in the case of inversions, and can causes sampling errors of storms. 4. Ground clutter- Overestimates precipitation intensity for echoes near the radar site. Ground clutter will be reduced by using a higher tilt angle. Ground clutter also tends to be less when the lower troposphere is unstable. 5. Beam spreading- The resolution of range gates decreases as range from the radar increases. Precipitation areas will look bigger and pixilated at the longer ranges. 6. Attenuation- Radar beam is less powerful as it moves into the longer ranges from radar as the radar beam moves through precipitation areas that scatter away the beam progressively as it moves away from the radar. This causes an underestimation of echo intensity at the long radar ranges. 7. Unsampled regions- The cone of silence (cone created immediately above radar bounded by rotating highest tilt angle used 360 degrees) is not sampled. The regions below lowest tilt angle is also not sampled. 8. Location of precipitation- Position of precipitation aloft may not be position precipitation strikes the Earth's surface. 9. Virga- Often much of the light precipitation that shows on radar evaporates before reaching the ground. |