Synoptic, Thermodynamic, Shear Setting May 7, 2002 Tornadic Thunderstorm in Southwestern Kansas Michele Blazek May 15, 2005

Synoptic Setting – What to look for  Warm advection –Found through height changes and the sounding –Moist air advection into the jet stream  Deep layer shear –Approximated using the difference in the wind vectors between the surface (surface chart) and 500 mb –Sustains the development of storm  Low level shear - –Must be strong enough even with deep layer shear to sustain a supercell

500 mb Wind Direction/Speed Note the area in SW Kansas with just east of the trough in the rockies, ageostrophic winds in Central Kansas and significant favorable deep layer shear - 50 kt or 5.0 E-3 /s 500 mb Chart 00 UTC 08 May 2002, Observations Heights, Temperatures

Mesoscale Surface Chart Note location just east of the low and dryline and just north of the area of warm, wet advection

Satellite Imagery – what to look for  Presence of Cumuloform formations - especially cumulonimbus anvils (CBA)  Continued development of these anvils

Visible Satellite Note the overshooting cumulonimbus anvils in Central Kansas 2145 UTC 07 May 2002 Visible Image UCAR

Visible Satellite - Kansas Note the developing overshooting cumulonimbus anvil expanding from S Central Kansas to the Northeast of the State 2315 UTC 07 May 2002 Visible Image UCAR

Thermodynamics – what to look for  Presence of CAPE  Possibility of CAPE developing throughout the day  Advection of high dew-point air north to the jet stream  Winds directions and shear

Shear – what to look for  Hodograph –Shape of hodograph - curved hodograph - possible supercell –Storm Relative Helicity spin due to vertical shear (curved hodograph)  SREH > 150 tornadoes  SREH> 250 F2, F3 –Storm Motion  Shear –Deep Layer 0-6 Km (500 mb) Greater than 35 hts and right angles to winds at 18,000 ft - favorable to midlevel mesocyclone development –Shallow Layer

Topeka Sounding Note Huge shear 69 kt E-3/s And helicity 0-1 km 445 m 2 /s km 690 m 2 /s 2 Note the curving Hodograph Indicates Storm relative Helicity from 0-3 km! Shotgun Sounding – Significant CAPE as As day progresses!

Oklahoma City Sounding Note the CAPE of over 4000 J/kg. The deep shear is 49 kt E- 3/s. Low level shear is smaller than Topeka. Significant CAPE The shape of the hodograph suggests some SREH.

Radar Reflectivity Note the supercell on radar and the split from 6:47 to 7:07 pm near Dodge City, May 7, 2002 Look at the hook!