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A CASE STUDY OF THE GREAT PLAINS BLIZZARD OF 27-28 NOVEMBER 2005. P. S. Market, C. J. Melick, B. P. Pettegrew, A. E. Becker, and L. L. Smith Department of Soil, Environmental and Atmospheric Sciences University of Missouri-Columbia Presented at the Winter Weather Workshop - PowerPoint PPT Presentation
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A CASE STUDY OF THE GREAT PLAINS BLIZZARD OF 27-28 NOVEMBER 2005
P. S. Market, C. J. Melick, B. P. Pettegrew,A. E. Becker, and L. L. Smith
Department of Soil, Environmental and Atmospheric SciencesUniversity of Missouri-Columbia
Presented at the Winter Weather Workshop National Weather Service Office, Pleasant Hill, MO
29 October 2007
With the aid of…
• John Stoppkotte, SOO
North Platte, Nebraska, NWS
• UMC students enrolled in
ATMS-4720, Synoptic Meteorology II
• The National Science Foundation
Introduction
• Analysis of occluded cyclone– Well-developed trowal structure
• Multiple bands of precipitation
• Blizzard conditions for an extended period in LBF CWA
• Lightning activity present but limited
gusts(mph)
snow(in.)
Courtesy, NOAA/NWS LBF
Purpose
• Assess the nature of the unique trowal structure– Influence on banded precip?
• Assess lightning observations– Are they valid?
• Assess the production of extreme winds
gusts(mph)
snow(in.)
Courtesy, NOAA/NWS LBF
- Synopsis -
12Z 2005 Nov 28
12Z 2005 Nov 28
12Z 2005 Nov 28 – 925 mb
12Z 2005 Nov 28 – 850 mb
12Z 2005 Nov 28 – 700 mb
12Z 2005 Nov 28 – 500 mb
12Z 2005 Nov 28 – 300 mb
12Z 2005 Nov 28 – RADAR
Storm total snow (in.) , 27-30 Nov 2005
- Event Specifics -
2005 Nov 28 – Surface Obs
• KAUH 1310Z +SN LTG DSNT SW– With NLDN flash near this time
• KVTN 1622Z, 1652Z, 2008Z, 2032Z, 2052Z, 2109Z TSSN
– KAUH – Aurora, NE– KVTN – Valentine, NE
2005 Nov 28 – NE Sfc Stations
2005 Nov 28 – 1300Z
• Initial development of lightning and thunder
• Reported in Aurora, NE, METAR
• Corroborated by NLDN
2005 Nov 28 – 13Z RUC20 – AUH Sounding
2005 Nov 28 – 2100Z
• Redevelopment of lightning and thunder
• Emergence of trowal feature– And a unique double trowal signature
• Evolution of meso- circulations
• Significant banded precipitation underway
2005 Nov 28 – 19Z RUC20 –VTN Sounding
2005 Nov 28 – 21Z VIS Sat
2005 Nov 28 – 21Z IR Sat
2005 Nov 28 – 21Z WV Sat
2005 Nov 28 – 21Z Sounder CTP
2005 Nov 28 – 21Z RADAR
2005 Nov 28 – IR Loop 13Z-23Z
2005 Nov 28 – RADAR Loop 18Z-23Z
- Trowal Structure -
Various Model Solutions for trowal21Z Nov 28 2005 – 308 K e
Cross Section through Double trowal2100V009 Nov 28 2005 – NAM 212 Trowal Surface
Cross Section through Double trowal21Z Nov 28 2005 – NAM 212 Grid Cross Section
WRF 12-km SolutionsValid 21Z Nov 28 2005 – 21 hr Solutions Reflectivity (Shaded & contoured)
WRF 12-km SolutionsValid 21Z Nov 28 2005 – 21 hr Solutions Reflectivity (shaded) with θe
WRF 12-km SolutionsValid 21Z Nov 28 2005 – 21 hr Solutions θe - Full Physics (green) / No microphysics (brown)
WRF 12-km SolutionsValid 21Z Nov 28 2005 – 21 hr Solutions θe (white contours)
WRF 12-km SolutionsValid 21Z Nov 28 2005 – 21 hr Solutions Reflectivity with ω
Conclusions
• AUH - 13Z - One NLDN CG flash establishes a history of electrical activity
• VTN - 16Z, 20Z, 21Z – METARS report TSSN based upon surface sensor– Valid, to the best of our knowledge
• Also, soundings support existence of lightning
Conclusions
• Existence of double trowal appears valid– Reason(s) for creation of the structure are
unclear– Structure seems to have some bearing on
banded precipitation development and/or evolution
• The trowal aspect of this cyclone warrants further study
Thank you!
Questions?Comments?
ROCS Homepage : http://weather.missouri.edu/ROCS/