A Change In The Calendar; A Change In The Weather - But For How Long?

Before you go saying June's been a rather cool month; you might want to look at the actual temperatures and departures. Believe it or not, June 2018 has averaged a degree /+1.1/ above normal for nearly the first third of the month (through the 9th). Why it feels so cool is coming off the second warmest May on record; especially the latter third or so. The comparison of high temperatures and departures is quite dramatic...


    MAY 2018<              >JUNE 2018

May 23-31 was exceptionally warm and more like a mini-heatwave in the middle of the summer; whereas June 1-9, temperatures dropped considerable to basically, normal levels for early June. No where than the daily high temperatures and daily departures (both highlighted in yellow) is this displayed better. However; short term indications are for June's "cool spell"  to heat up going into the middle of the month.

Back to the data; the daily rainfall (WTR) might have caught your eye;after a early and middle wet May, things are beginning to dry out some, depending on your location. Lighter rains fell in some parts of metro Detroit while heavier rains fell in other areas. Heaviest rain this past weekend was across Shiawassee and Genesee Counties where reports of of up to two inches were reported.

So what about the whole month of June?

While the June analogues were mixed; there was a lean toward an average to a slightly below June temperature month. Five June's averaged below normal (more than 0.3 of a degree); four averaged normal (within 0.3 of a degree and three above (better than 0.3 of a degree). I cut the temperature categories down smaller to a third of a degree; just for a closer representation of actual numerical departure. This has nothing to do in the analogue performance since I use a whole degree for the season as being above, below or normal. The same goes for the departure in rainfall categories; using better than a third of an inch for above or below, or within a third for normal (see Month Legend).

Rainfall leans toward below the average in June with six below normal, three normal and three above. During the summer with convective rains this tends to be quite variable but the basic trend did show drier than average in area coverage.

I thought the analogues were a bit too cool this season, one reason was their comparison to today's norms which have risen over the decades (discussed in Summer Outlook); partly reflecting the metro heat island. Therefore; I'm looking for a temperatures to average normal to above for the entire month of June with below normal rains dominating the countryside.  

JUN	DEPART
T	"+/- N"
70.7	1
68.7	1
69.5	1
66.6	2
67.8	3
70.6	2
62.8	4
69.4	2
69.5	3
69.3	4
67.8	5
72.3	3
68.8
69.4
-0.6
JUN	DEPART
P	"+/- N"
2.63	1
1.82	2
1.48	3
3.30	1
3.13	4
3.26	2
1.62	5
4.90	1
3.40	3
3.95	2
5.27	3
1.31	6
3.00
3.52
-0.52
Month Legend:
Temps	Degrees
Below	" >-0.3
Normal	"-0.3 - +0.3
Above	" >+0.3
Rain	Inches
Below	" >-0.33
Normal	"-0.33 - +0.33

Above

" >+0.33

Making weather fun while we ALL learn,
Bill Deedler - SEMI_WeatherHistorian