Concentration risk in the Mag 7 and the communications services sector is something that Charles Schwab's Kevin Gordon considers a "yellow flag." He wouldn't be surprised if there's a pullback on weakness in those names, or if the Fed signals more hawkish-than-expected commentary from Wednesday's meeting. Kathy Jones tells investors to watch bonds. While she doesn't expect a bond rally, changes in the yield curve can offer signs of future price action.