VORTEX Chase Summary
Fig. 1. 0100 UTC Surface Map. Standard station model used: temperature and dewpoint (F), pressure (mb), sky conditions, and precipitation.
Winds in knots with one pennant, one full barb, and one half barb equal to 50, 10, and 5 knots, respectively. Pertinent surface features depicted; MSLP contoured every 2 mb.
Note, ASOS/AWOS specials were utilized in the subjective analysis but removed for image
clarity. If subjective analysis suggested stations were generating erroneous variables, those variables were then omitted
from analysis. The surface data seven hours prior to 0100 UTC were analyzed to minimize feature(s) error.
Fig. 2. 0100 UTC GOES-8 visible with surface data overlay. Surface features
depicted as in Fig. 1; altimeter shown in mb. Satellite image courtesy of CIMMS-UWI.
Fig. 3. Base reflectivity from KDLH at 0025 UTC. Approximate location of Braham tornado and MM' depicted.
Fig. 4. As in Fig. 3 but for the Siren tornado at 0112 UTC.
Fig. 5. As in Fig. 4. but for 0124 UTC.
Fig. 6. As in Fig. 4. but for 0142 UTC.
Fig. 7. Image of the tornado at 0106 UTC west of Siren.
Fig. 8. As in Fig. 7. except for the time of 0112 UTC.
Fig. 9. As in Fig. 7. except for the time of 0116 UTC.
Fig. 10. As in Fig. 7 except for the time of 0118 UTC.
Fig. 11. Skew T-log p diagram depicting the 0000 UTC 19 June MXP sounding.
Pressure are in mb, and temperatures are in Celsius. Winds as in Fig. 1. The parcel process curve is for a parcel lifted with the mean potential temperature
and mixing ratio of the lowest 50 mb (parcel theory). Values of CAPE and CIN were computed based on the virtual temperature buoyancy.
Fig. 12. 0000 UTC 19 June 2001, Storm Prediction Center 925-250 mb upper air charts
Fig. 13. Blue River, WI, hourly profiler data for 1300-2000 UTC 18 June 2001. Winds as in Fig. 1. Heights in meters AGL.
Fig. 14. As in Fig. 13 except for the times 0000-1000 UTC 19 June 2001.
Fig. 15. Hodograph for 0000 UTC 19 June 2001 Blue River, WI. profiler. Winds m s-1; heights in meters AGL.
Fig. 16. Blue River, WI, weekly profiler data. Winds as in Fig. 15.
Fig. 17. As in Fig. 13 except for Wood Lake, MN
Fig. 18. As in Fig. 17 except for the times 0000-1000 UTC 19 June 2001.
Fig. 19. As in Fig. 15 except for Wood Lake, MN.
Fig. 20. MM data plot of the western (rear) periphery of the Braham tornado
Fig. 21. MM data plot of the Siren tornado as it developed near Grantsburg, WI.
Fig. 22. MM data plot of the tornado cyclone associated with the Siren tornado.
There are a several good web pages focusing on this event. Instead of reinventing the wheel with duplicate products, I'd
rather point you directly to these pages.
DLH NWS DAMAGE ASSESSMENT
UNIVERSITY of WI SIREN CASE STUDY PAGE
UNIVERSITY of WI LANDSAT-7 IMAGERY
RUC-II data by Jon Davis