Impacts of VORTEX2 Observations on Analyses and Forecasts of the 5 June 2009 Goshen County, WY Supercell

Impacts of VORTEX2 Observations on Analyses and Forecasts of the 5 June 2009 Goshen County, WY SupercellTimothy A. Supinie, Youngsun Jung, and Ming XueEnKF Workshop20 May 2014MotivationWarn-on-Forecast project (Stensrud et al. 2009)Issue tornado warnings based on forecasts, not detectionHow well can we currently forecast supercellsWith routine observations?With special (VORTEX2) observations?VORTEX2 ProjectVerification of the Origins of Rotation in Tornadoes EXperiment (2009-2010)Mobile radars, mobile mesonets, disdrometers, photogrammetryIncrease conceptual understanding of supercellsGoshen County supercell one of four tornado cases from 2009Only Strongly Tornadic case

Observations Used

Routine:WSR-88D radarsAutomated Surface Observing System (ASOS)Wind ProfilersVORTEX2:MWR-05XP X-band radarNSSL Mobile MesonetsTTU SticknetMobile SoundingsExperiment Setup

3 km1 kmARPS v5.3EnSRF40 Ensemble MembersTwo domainsInner (1 km grid spacing)Outer (3 km grid spacing)Member-by-member BCSelected Configuration SettingsOuter DomainInner DomainGrid Size408 408 51252 252 51Horizontal Grid Spacing3 km1 kmVertical GridHyperbolic Tangent Stretching, 50 m minimum spacingInitial Conditions12 UTC NAM + 3DVAR21 UTC Outer DomainBoundary ConditionsNAMOuter DomainMicrophysicsLin et al. (1983) + Reduced N0r (4 105 m-4)RadiationGoddard (SW: Chou, 1992; LW: Chou and Suarez, 1994)PBL1.5-order TKE (Deardorff, 1980)Radar Localization Radius6 km (2x)6 km (6x)Radar Error Std. Dev.3 dBZ, 5 m s-15 dBZ, 7 m s-1Covariance InflationMultiplicative ( = 1.2) + RTPS ( = 0.9)Experiments PerformedCTRL: All Routine and V2 ObservationsNO_MM: Deny Mobile MesonetNO_MWR: Deny Mobile Radar (MWR-05XP)NO_SND: Deny Soundings

NO_MM_MWRNO_V2Reflectivity Loop

Observation-Space Statistics

Impact of Mobile Sounding Data

0.10.20.30.40.50.60.70.80.91.0Impact of Mobile Sounding Data

2140 UTCImpact of Mobile Mesonet Data

0.10.20.30.40.50.60.70.80.91.0Impact of Mobile Mesonet Data

Impact of Mobile Mesonet Data

-5.5-5.0-4.5-4.0-3.5-3.0-2.5-2.0-1.5-1.0-0.50.51.01.52.02.53.03.54.04.55.05.5MM Car #2 (P2)uvImpact of Mobile Radar Data

0.10.20.30.40.50.60.70.80.91.0Impact of Mobile Radar Data

0.10.20.30.40.50.60.70.80.91.0ConclusionsMobile sounding obs have a positive impact on a 1-hour forecastCaveat: No routine sounding observationsMobile mesonet obs have a negative impact on a 1-hour forecastUnrepresentative wind observationsMobile radar data has a positive impact on a 1-hour forecast when the analysis is suboptimalLittle effect otherwiseImpact of Mobile Mesonet Data

7.510.012.515.017.520.022.525.027.530.0

Conventional Data Assimilation Parameters