Figure 4

Estimated (a) propagation speed and (b) back-azimuth for both MCSs.
The speeds of the first MCS (black) and second MCS (gray) are calculated starting when the MCS moves over Chesapeake Bay and ending when the MCSs dissipate or are out of the range of land based radar. Time is in hours from 0000 UTC on June 13. The meteorological convention is used here, whereby the back-azimuth is the direction from which the disturbances originate.