1. PECAN CSWR interest IOP 27 12/13 July 2015 MCS in SE Minnesota

2. Overview Map * Dows are blue disks * Dual lobes are 30 o min crossing: Red: D8-D6 Light Blue: D8-D7 Dark Blue: D7-D6 * Black circles: each radar’s data range * Two brown lines are gust front at 05:36 (top) and 06:30 (bottom) * Light green polygon is where CI occurred (in SW part) and moved NE. * Low-level blockage is shown as grey sectors for each radar. * Dashed red line with X’s is the path of a gust-front vortex just NE of D6. Another vortex was following about 7 km NW of it.

3. Dual Map for Gust Front A subset of Overview Map showing northern area where gust front was best seen. Note that on the gust front for 06:30, thickened for clarity, there is a kink northward just E of Dow6. This is where the main vortex (dashed red line with X’s) was at 06:30. D6 D7 D8

4. Dual Map for CI Area A subset of Overview Map showing area where possibly pristine CI took place. Several cells initiated in the SW part of the green polygon and moved NE-ward within the polygon. Unfortunately there are blockage shadows (shown conservatively as grey sectors for each radar) which somewhat limit dual potential here. D8 D7 D6

5. DOW views of Gust Front approaching Simultaneou s view of gust front (DBM top, VEL bottom) for each radar at about the same time at elevation 1 o. All are centered at the same geographic location using one instance of soloii. DOW-8 DOW-6 DOW-7

6. DOW views of Gust Front at each radar Simultaneous view of gust front (DBM top, VEL bottom) for each radar at about the same time at elevation 1 o. Each is centered at the respective radar. Passage at each radar was nearly simultaneous! DOW-8 DOW-6 DOW-7

7. DOW views of Vortex from each radar Simultaneous view of vortex (DBM top, VEL bottom) for each radar at about the same time at elevation 1 o. Each is centered NW of the vortex. Max Dv=40 m/s over 2.0 km at Z=86m. Note reflectivity curl. DOW-8 DOW-6 DOW-7 Vortex is indicated by black circle only once for clarity. At time of best form and strength.

8. Maximum low-level wind at each radar Wind maxes listed below are circled in black on sweeps. Dow-8: -22 m/s at Z=18m. Dow-7: -24.6 m/s at Z=6m and +25.9 m/s at Z=8m. Dow-6: -25.9 m/s at Z=12m. DOW-8 DOW-6 DOW-7