Temperature trend lines for May, 2010-2017.
(Copyright © 2017 by Wil C. Fry. Some rights reserved.)
May 2017 was cooler than the eight-year average for May, but only barely. It’s the first year this month that wasn’t warmer than its average. May 2012 remains the warmest May on record. April and May this year were something of a relief, since the previous two months set all-time records for warmth.
As May’s temps leveled off the past four years, they began to match well with October — which has been warmer than usual recently. Note on the graph above, the most recent green lines cross right through October dots.
We didn’t set any daily records this May, either lows or highs.
I measured 2.22 inches of rainfall for May 2017. This would be decent for most months, but May is our rainiest month on average. This is the least rainfall we’ve received in May since 2010. However, 15 separate days saw precipitation, which is more than average. (Most of those days, the precipitation was observed, but not enough to measure.)
We’re on track to have either the hottest year on record (beating 2012) or the second-hottest year, behind 2012. Our combined January-thru-April HLA has never been this warm, and this is the warmest May since 2012. That year, January through May and December all set records, three of which still stand. (This year, February and March surpassed 2012’s records.) No other year is comparable with 2017’s heat so far.
The lows from February through April were warmer than they’ve ever been, and our last freezing day was in the second week of January.