1 A dual-polarization radar hydrometeor classification algorithm for ...

908909910911912913914915916917918919920921922923924925926927928929930931932933934935936937938939940941942943944Figure Captions.Fig. 1: K dp , Z dr , and Z h electromagnetic scattering simulations of plate crystals (purple), dendriticcrystals (blue), dry aggregated snowflakes (green), sleet (orange), and rain (red) at X-, C-, and S-band frequency according to microphysical parameterizations in Table 1. Note: same colorconventions used throughout this studFig. 2: K dp , Z dr , and Z h electromagnetic scattering simulations of rain (RN-red) at X-, C-, and S-band, freezing rain (FR-dark orange cross-hatched) at C-band only, and sleet (SL-orange) at X-,C-, and S-band. Rain fall behavior was modeled for sleet version SL_1, while increased tumblingbehavior consistent with graupel was simulated in sleet version SL_2 (whose values appear inFig 1. and Table 2).Fig. 3. Skew-T diagrams from KOUN (Norman, OK), nearly collocated with OU-PRIME.Surface precipitation type was freezing rain at 15 and 18 UTC but sleet at 21 UTC.Fig. 4: C-band OU-PRIME Z h , Z dr , K dp , and ! hv PPI scans at 2.4° elevation angle throughstratiform precipitation with a dendritic growth zone aloft in the southwest quadrant at 1545UTC on 28 Jan 2010 when METAR reported freezing rain at the surface.Fig. 5: Winter hydrometeor classification algorithm steps: a) melting layer (ML) detection, b)below ML, c) above ML, and d) final HCA output for same C-band OU-PRIME PPI scans inFig. 7. Final classification includes plates (PL-purple), dendrites (DN-blue), dry aggregatedsnowflakes (AG-green), wet snow (WS-yellow), freezing/frozen raindrops (FZ-orange), rain(RN-red), and no echo (NE-white) indicating clear air or ground clutter.Fig. 6: X-, C-, and S-band membership beta functions (MBFs) for the melting layer (ML)detection HCA. Categories include wet snow and “other,” which accounts for aggregates andlight rain.Fig. 7: X-, C-, and S-band membership beta functions (MBFs) for the HCA used below themelting layer (ML). Categories include freezing/frozen rain and rain.Fig. 8: X-, C-, and S-band membership beta functions (MBFs) for the HCA used above themelting layer (ML). Categories include dry aggregated snowflakes, dendrites, and plates.Fig 9: C-band OU-PRIME Z h , Z dr , K dp , and !hv 330° RHI scans at 2220 UTC on 28 Jan 2010through stratiform precipitation once sleet had been reported in the Oklahoma City area byMETAR.Fig. 10: X-band CASA KSAO Z h , Z dr , ! hv , and HCA 270° RHI scans at 1422 UTC on 24 Dec2009 perpendicular to a vertical bright band. Freezing rain and sleet are classified between 0-10km range, melting, a concentrated region of wet snowflakes reach the ground around 12 km, anddry aggregated snowflakes are indicated at farther ranges. Central and southwestern OK METARreports confirmed passage of a similar precipitation transition event between 14-16 UTC.Fig. 11: X-band CASA KCYR Z h , Z dr , K dp , and HCA 50° RHI scans at 1518 UTC on 24 Dec2009 through a dendritic growth zone aloft when METAR snow reports occurred at the surface44