Summer Peak Timing
Median summer peak Aug 3; September is the weakest month. Early peak (pre-mid-July) → Q3 negative 68% of the time (median -3.5%) vs +3.4% for a late peak.
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When does the S&P 500 top out in summer? The high lands ~Aug 3 (median); July is the last strong month, September the weakest of the year. An early peak (before mid-July) preceded a negative Q3 ~3/4 of the time. With midterm / year-ending-6 / Q1-down-Q2-up cohorts and this year’s analogs.
- 77 signals since 1928-01-01.
- Median summer peak Aug 3; September is the weakest month. Early peak (pre-mid-July) → Q3 negative 68% of the time (median -3.5%) vs +3.4% for a late peak.
When to run this study
Run June–September. Frames where the S&P typically makes its summer high (median Aug 3), the September soft patch, and — the key watch — whether the current year makes a fresh high after mid-July (healthy) or has already peaked (early peaks preceded a negative Q3 ~3/4 of the time).
Historical results
Summer peak by cohort
| Cohort | n | Median peak | Avg peak | Climb to peak | Peak→fall low | Q3 |
|---|---|---|---|---|---|---|
| All years | 77 | Aug 3 | Jul 30 | 10 | -7.10 | 2.50 |
| Midterm (yr 2) | 20 | Aug 16 | Aug 5 | 5 | -9.40 | 3.50 |
| Year ending in 6 | 8 | Aug 8 | Jul 30 | 10 | -7.20 | 1.50 |
| Q1 down + Q2 up | 17 | Aug 3 | Aug 2 | 7 | -6.80 | 3.10 |
| Midterm + Q1↓Q2↑ | 4 | Aug 15 | Aug 11 | 9 | -10.80 | 4.60 |