Temperatures:
Overall; I look for temperatures to average around normal or within -1 1/2 to +1 1/2 degrees of the normals for Southeast Lower Michigan. As far as the patterns researched and analogue projections; see my Temperature trends discussion under analogues.Rainfall:
Look for the general pattern of above normal rainfall to continue into the summer across Southeast Lower Michigan. Analogue summers showed many wet summers with rainfall a couple of inches above normal on average. As far as the pattern researched and analogue projections, see my Rainfall trends discussion under analogues.Spring Finally Sprung
The upper air pattern has been very repetitious as of late; basically continuing the general pattern of the winter albeit with obviously; somewhat warmer weather. But not that warm as the Spring of 2019 has gone down in history as a cooler than average spring. May averaged about a degree below normal across Southeast Lower Michigan; April came in-line with normal while March was the biggest offender; averaging close to three degrees below normal! On the whole; Southeast Lower Michigan averaged a degree or two below normal for the entire spring, depending location. Coolest was across the Saginaw Valley and Thumb.
And yes, it's been a wet spring across much of Southeast Lower Michigan with the exception over the Saginaw Valley. The wettest month relative to normal was April.
Hemispheric Discussion
Above average SST's continue the weak El Nino over the Pacific for our summer with SST's hovering just a titch above normal. Look for the SST's to return closer to normal later this Fall. As of this writing; next winter the ENSO looks to be either a Neutral ENSO or possibly even the beginnings of a La Nina. Note the latest CFv2 is hinting at a collapse of SST's later this summer into the Autumn.
The Analogues for the Summer show some interesting trends:
Temperatures Trends by Month:
Let's start with June; a cool or below normal June? That's what all my data is pretty well showing; from analogues, to current and projected upper air patterns, CFS Climate model which looks out over most of June and CFSv2 model, for all of June. Can't argue much with that; though anything can happen we could be all wrong ;-) Let's hope we can slide by with a "closer to normal" June. Also, many times changes occur mid or late month and this June could very well be one of those and warm up with time.Even though they were just as many cool Junes as warm Junes in the analogues (5/5); the difference here was the cool June departures were more notable than the warm departures for June. The five cool Junes averaged in at 64.7; well below the June norm of 69.4. These cool Junes averaged just under five degrees below normal and were precisely why the average for all of the June sample came in below normal also, at 68.6 /-0.8/. On the flip-side; the warm June's averaged in at 71.9 or 2 1/2 degrees above the June norm or just about half of the cool departure. There was just a couple of normal Junes in the 12 numbered sample
Things started to heat-up in July as well they should with six Julys above normal, averaging better than the degree needed for an above normal month. The normal Julys placed a close second with five in number with only one cool July - a far cry from June's stats. Overall, the July temperature averaged +0.6 above normal but again not enough to declare the month - by average - a categorized above normal month. Still, there were quite a few notably warm Julys with the above normal six averaging 75.8 or better than two /+2.2/ above normal.
By August; a bit closer to a normal temperatures were found but with the above normal Augusts just winning out at five; there were four normal Augusts and three cool Augusts. Average temperatures dropped slightly to 72.3 for all 12 August months. However; again like the Julys, the warmer, above normal Augusts average at 74.7; nicely above /+2.7/ over the 72.0 norm.
Summers:
What all this data leads to is five cool summers; four warm summers and three normal - or average summers in our sample this go-around. And as one would think: this averages to a strong likelihood of a normal or average summer with ironically the mean temperature at Detroit coming in right at normal with 71.7 degrees on the analogues.Analogue trends suggest a cooler than average June and a normal to above normal July and August. This then leads to basically a normal summer. A lot will deal with the evolution of the upper air pattern that's been overall; holding to the pattern established way back in the winter. The Pacific jet fighting for dominance - and winning more often than not- over the Polar Jet over central and eastern Canada. This would be expected for two reasons once the normal retraction of the summer-time Polar Jet and two; the Pacific Jet remains somewhat energized due the the warm waters of the Pacific.
Rainfall:
The strongest trend seen in the rainfall side of the analogues is above normal rainfall. Half of the analogues showed above normal rainfall with another three denoting normal or average summer rainfall. That only leaves three drier than average summers in the sample of 12. While the average rainfall for all of the summers comes in at 11 1/2" of rain /11.54"/ and well above the 9.89" normal; this doesn't average just the wet summers. At that pace; the six about normal rainfalls average in at a whopping 13.90" - a very wet signal. Being these are just half of the analogue members; generally that's not strong enough of a signal to use alone. However; besides the six wet summers, there were the three normal which boost it up to nine normal to above normal rains which leaves us with an average rainfall of 12 1/2" /12.49'/; still comfortably above the 9.89" Even the drier summers weren't all that terribly dry with the three averaging at 8.66". A quite interesting and sort of a weird fluke; all three dry summers totaled at: 8.67, 8.66, 8.66".While all months averaged above normal for rainfall; basically as the summer went on the chances are it gets warmer and wetter. That's pretty simplistic but in some regards; makes sense. As the warmer air surges northward more often during the summer, I look for more occurrences of severe weather.
Model Projections:
The models temperatures projections are in fairly good agreement for the monthly outlooks with generally a near normal outlook; while the three month season is in good agreement. Looking at the month's individually: June does suggest a lean toward below normal, July; a lean toward above normal and August normal - not unlike the detailed analogues. Therefore; the monthly computer broad-scale projections of the model do reflect the analogue details.
A consensus of the foreign models suggest a near normal temperature summer also. Interestingly; the large area of below normal temperatures in the mid part of the country is reflected by both the foreign models and American and actually; encroaches the western Great Lakes.
