It seems that even with the Pacific Ocean in a normal state (and not in an El Niño state), the year 2017 is going to be quite warm. Even though there are still months to go, it could end up being one of the top three warmest years ever (measured instrumentally, that is). Because 2017 hasn't received the El Niño temperature kick, this is somewhat unusual -- and unnerving.
The reason for the unnervingness is that it could indicate that some of the factors which have held back warming (for whatever cause) aren't in play now. So the heat could be on -- for real.
"Usually we see global records in years when the short-term El Niño warming adds to the long-term global warming trend (see chart below). As NOAA noted in its March report, without an El Niño, no month before March 2017 had ever exceeded the “normal” temperature (the 1981–2010 average) by a full 1.8°F (1.0°C)."