Nicholas Carletta Mentors: William Gallus, Michael Fowle, and Daniel Miller

 Hypothesis  What is Wind-Driven Hail?  Methodology  Morphologies in Wind-Driven Hail Cases  Comparisons of Environmental Parameters  Conclusions

 Wind-driven hail events occurred most frequently with certain storm morphology and these storms had high values of CAPE and SRH, as expected of a high end severe event like wind-driven hail.

 An event where severe hail greater than 1 inch in diameter occurs simultaneously with severe wind in excess of 50 knots/ 58 mph Credit for picture: Karl Jungbluth

Severe wind damageSevere wind-driven hail damage Credit for pictures: Michael Fowle

 103 mph wind and 3 inch hail reported  Crop Damage $175 million+ Picture and information from Karl Jungbluth NWS-Des Moines

Credit for pictures: Michael Fowle From Otho, Iowa near Fort Dodge during 8/9/09 event

Damage from Eldora, IA Credit for picture: Karl Jungbluth

 Severe wind reports and hail reports >1 inch that occur within 5 miles of each other no more than 30 minutes apart obtained from the National Climatic Data Center’s Storm Data  69 cases in 2002 and 69 cases in 2007  Morphologies assigned from Duda and Gallus (2010) and Gallus et al (2008) data

Picture from William Gallus

 Supercell data from Gallus and Duda (2010)  Categories from strength of event  30 Wind-only, 30 hail-only, and 14 known base cases to compare  Archived 00 hour RUC data analyzed with GEMPAK for CAPE and SRH

Wind-driven Hail from 2002 Wind-driven Hail from 2007

CategoryCAPE Average (J/kg) 0-3 km SRH Average (m 2 /s 2 ) CAPE Standard Deviation (J/kg) 0-3 km SRH Standard Deviation (m 2 /s 2 ) Wind-only Hail-only Known

MorphologyCAPE Average (J/kg) 0-3 km SRH Average (m 2 /s 2 ) CAPE Standard Deviation (J/kg) 0-3 km SRH Standard Deviation (m 2 /s 2 ) BE BL CC IC LS NL NS PS TS

CategoryCAPE Average (J/kg) 0-3 km SRH Average (m 2 /s 2 ) CAPE Standard Deviation (J/kg) 0-3 km Standard Deviation (m 2 /s 2 )

Supercell?CAPE Average (J/kg) 0-3 km SRH Average (m 2 /s 2 ) CAPE Standard Deviation (J/kg) 0-3 km SRH Standard Deviation (m 2 /s 2 ) Yes No

The NS, TS, IC, and CC morphologies over the two years were the most frequent The CC, IC, and NL morphologies were the most frequent morphologies higher categories

0-3 km SRH was significantly smaller for the wind-driven hail events than in the wind-only and known events Higher CAPE is present in supercells during wind-driven hail events Events with larger hail and higher winds had higher CAPE values than events with smaller hail and lower wind speeds

 Expand to additional seasons  More environmental parameters

 William Gallus  Michael Fowle  Daniel Miller  Karl Jungbluth

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