Fig. 3: Changes in daily steering wind regimes between current and future climates in the Large Ensemble Community Project (LENS) dataset.

Vectors of daily June to September steering wind are classified into 10 clusters using the self-organizing map (SOM) analysis applied to the current (1979–2005) and future (2074–2100 under RCP8.5) periods combined together. All cluster centers and their frequencies are shown in Supplementary Fig. 13. For each cluster i, the frequency \(f_i^{\mathrm{C}}\) \((f_i^{\mathrm{F}})\) is defined as the number of days in the current (future) period in that cluster divided by the total number of days in the current (= future) period. Panels a–c and g, h show the cluster centers and their frequency, \(\bar f_i = (f_i^{\mathrm{C}} + f_i^{\mathrm{F}})/2\), for the five clusters with the largest changes between the future and current climates. Numbers in parentheses are the change in the frequency of patterns within each cluster (\(f_i^{\mathrm{F}} - f_i^{\mathrm{C}}\); see Supplementary Fig. 14). Clusters C1, C4, and C5 (C6 and C9) have strong northward (southward) steering winds over Texas. Panels d–f and i, j show the change within each cluster due to change in frequency and change in pattern (future minus current; see Supplementary Fig. 16). k (m) shows the change, future minus current, in clusters with weak or northward (southward) steering winds over Texas. Panel (n) shows the change across all clusters, i.e., the sum of the changes in panels k and m, which is approximately the change in June to September-averaged steering wind vectors. Panels a–c and g–h, panels d–f and i, j, and panels k–n have the same colorbars. The arrow size and colormap of panels d–f and i, j (panels k–n) are scaled such that their values are 1/10 (1/5) of those in panels a–c and g–h.