WSR-88D Observations of mesoscale precipitation bands over (1997)

Content Provider	CiteSeerX
Author	Grumm, Richard H. Nicosia, David J.
Abstract	Weather Surveillance Radar-1988 Doppler (WSR-88D) located in central Pennsylvania detected a large area of snow, mixed precipitation, and rain over the central part of the state on 30-31 October 1993. It also detected an area of locally heavy rain over southeastern Pennsylvania on 4-S December 1993. In both cases, distinct bands of enhanced precipitation were embedded within broader areas of precipitation. The bands were oriented along the 1000- to SOO-mb thermal wind vector and were nearly parallel to the 8S0-mb isotherms. For both cases, the WSR-88D velocity azimuth display (VAD) wind profile (VWP) indicated a low-level northeasterly flow, which veered with height and became southwesterly aloft. Base velocity data from the O.S degree elevation scan revealed the clas-sic warm advection "S"~shaped _ pattern over central Pennsylvania. The base reflectivity data showed several bands of precipitation, which were later determined to have formed in a conditionally stable to conditionally neu-tral atmosphere. For the October case, the rain / snow line remained near or just east of the Radar Data Acquisition (RDA) site during the event, which resulted in bright band contamination of the base reflectivity data in the band near the RDA. In both cases, the precipitation bands formed in a jet entrance circulation with low-level northerly ageostrophic winds that reinforced the cold air. For the October case, the surface low and warm front remained well south of the area. Soundings from
File Format	PDF
Publisher Date	1997-01-01
Access Restriction	Open
Subject Keyword	Wsr-88d Observation Mesoscale Precipitation Band October Case Central Pennsylvania Base Reflectivity Data Mixed Precipitation Soo-mb Thermal Wind Vector Central Part Base Velocity Data Distinct Band 30-31 October 8s0-mb Isotherm Rain Snow Line O.s Degree Elevation Scan Neu-tral Atmosphere Wind Profile Southeastern Pennsylvania Several Band Warm Front 4-s December Radar Data Acquisition Enhanced Precipitation Heavy Rain Wsr-88d Velocity Azimuth Display Low-level Northerly Ageostrophic Wind Jet Entrance Circulation Clas-sic Warm Advection Bright Band Contamination Large Area Surveillance Radar-1988 Doppler Cold Air
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