Summary of Mobile Mesonet Observations on 3 May 1999 Paul Markowski School of Meteorology and CIMMS University of Oklahoma

Acknowledgments All VORTEX volunteers Erik Rasmussen Jerry Straka Al Pietrycha Joshua Wurman Curtis Alexander

The “Mobile Mesonet”

Objectives N N N T T T

Objectives Is there something “thermodynamically special” about hook echoes and RFDs associated with tornadic supercells?

Findings RFDs were relatively warm and moist Hook echoes lacked temperature gradients RFDs were associated with high pressure

Storm A

Storm A

Storm A

Storm A

Storm B

Storm B

Storm B

Storm B

Implications Evaporative cooling and entrainment of midlevel potentially cold air played a small or negligible role in the forcing of RFDs Does tornadogenesis probability, longevity, and intensity increase as RFD parcels become more buoyant? Microphysics parameterizations used by today’s cloud models cannot produce RFDs with the thermodynamic properties as those observed Are there any large-scale environmental conditions that favor one type of RFD over another? (5/3/99 argues that the answer is “yes”)