In a nutshell: All main guidance, El Nino Analogues and past El Nino sequencing with timing strongly suggest a normal to cooler summer accompanied by normal to drier rainfall summer.
Temperatures:
Look for temperatures to average from two degrees below normal (cooler summer) to one and a half degrees above (basically a normal summer). Analogues are tilted too much toward below normal temperatures with each month coming in at about two degrees below normal. Interesting noted was how each of the monthly average in the Summer Analogues came in at just over two degrees below normal (suggesting no preference between the months). That would intimate each summer month would average below normal -roughly by a degree or two.
Late Spring of 2026 appeared to be slyly suggesting cooler summer possibilities by recent weather patterns across the Great Lakes in May /Detroit -1.5F/ with average to cool weather dominating at the surface and aloft. Developing El Nino Summer Analogues are reflective of mainly normal to below normal temperatures Add to that, some of recent Summer Climate Model Guidance are also suggesting a cooler than average summer.
Rainfall
Past analogues suggest normal to below normal rain similar to model guidance. Unfortunately; summer season by nature is spotty with its feast or famine regiment by location.
Past Winter
Briefly looking back at our previous winter, the Winter of 2025-26 analogues & guidance also painted a colder than normal winter but with below normal snowfall. Certainly not a severe winter with above normal snow but prevailing below normal temperatures winter. Overall the forecast called for temperatures to average 1-3 degrees below normal and variable snowfall with a decided preference for below normal - unlike the northern Great Lakes which were clobbered with snow and rain. See; Winter 2025-26 in Southeast Michigan; Will it be as Rough as Many Say it Will?
As mentioned; looking ahead most guidance along with analogues suggests a normal to cool summer and in keeping with the observed general weather patterns in the past two seasons. In addition; normal to below normal precipitation showed a dominance.
Researching back to similar strongly building El Nino's places 1982 & 2015 very close to the SOI's thus far in 2026. Other closely aligning SOI's occurred in 1991. The well remembered El Nino of 1997 was ahead of this years SOI and actually started in early 1997.
Years that were selected with a quickly building El Nino, summer into fall/winter are a good set of strongly developing El Nino's.
1957, 1965, 1972, 1982, 1991, 1997, 2009, 2015 = 8 Analogues with red highlighted years the closest to the SOI timing (1982, 1991 & 2015) and 2009 has a similar pattern weather-wise spring into summer. The El Nino of 2009 came later in the year and was a moderate El Nino.
BUILDING EL NINO'S ~ SUMMER 2026 ANALOGUES
The varying upper flow already evident in the last several weeks has been developing the summer ridge over the central part of of the US. A projected upper air pattern was last seen in 2009, 2015 and the latest weaker El Nino but developed later in 2023. That summer too resulted cooler than normal -but was a wet summer. A notable blocking high pressure is establishing itself over the middle part of the country and is expected to oscillate from the Mountain West to the Eastern US. The last but not least is the upper air pattern system is the semi-permanent Upper Low over Southeast Canada - certainly capable of occasionally delivering cool Canadian air in the region. These main upper wind players will be the main drivers this summer.
A relatively glaring map of the upper air CanSIPS 850 mb summer pattern is suggesting cooler than average 850 temps over a large part of the the US - basically over two-thirds of the US. Coolest projections are over the central and southern Midwest/Plains into the Ohio Valley relative to average. The newer guidance will come in early June. Besides the latest 850 MB temperature projected on CanSIPS below; the Euro height projections below the 850 map; reflects the strong Polar lower heights reflecting the cooler player over Southeast Canada.
Recent Developments;
The recent dry spell that developed this May into June comes at a time which periods of rain for the growing season is needed. With just 2.20" of rain in May /-1.18"/ we are starting out drier in the surface moisture at 2"-4". Luckily; the heaviest rains fell in mid May but with drying above ground since, we need rain. That being said; the majority of latest models bring the increasing chances of rain later Friday into the weekend as temperatures and moisture increase.
Finally:
Therefore; the combination of upper ridging over the west into central US oscillating occasionally east through the summer. This; in conjunction with the semi-permanent Polar upper low positioning in southeastern Canada should temper long standing heatwaves leading to a more comfortable summer.
Try to enjoy the summer whatever the weather.
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