(a)
(b)
(c)
(d)
Figure 3: The 1200 UTC Northern Hemisphere 500 hPa height anomalies versus the 1981–2010 climatology for (a) 8 April 2014, (b) 20 April 2014, and (c) 28 April 2014, respectively, and (d) the Continental USA severe weather reports. The contours in (a), (b), and (c) are every 30 (m).