CME Futures Trading Halt: Cooling Failure & AI Infrastructure Stress Analysis

On November 28, 2025, the Chicago Mercantile Exchange (CME) halted futures and options trading across key asset classes (WTI crude, US 10-year Treasuries, S&P 500) due to a cooling system failure at CyrusOne’s Aurora, Illinois data center. The outage lasted ~10 hours before trading resumed. A Reddit discussion debated whether this was a one-off technical issue or a sign of broader infrastructure stress from AI-driven workloads, with additional points on failover planning and market implications.

a.

: CME halted trading for ~10 hours (Nov28, 2025) due to cooling failure at CyrusOne’s Aurora, IL data center, affecting derivatives across commodities, equities, and rates [1][3][5].
b. : 75% of new data center projects target AI workloads, requiring liquid cooling to manage heat/power demands (Turner & Townsend 2025 report) [6][8].
c. : CME’s stock (CME) closed +0.59% ($282.52) on the outage day, with a premarket dip [9][11].
d. : Rack density rose from7kW (2021) to16kW (2025) due to AI/HPC workloads; 79% expect further growth [7].
e. :

• Normal tech issue overhyped with AI (score=15) [13].
• Lack of failover shows lazy infrastructure planning (score=2) [13].
• Latency concerns prevent East Coast failover for high-frequency trading (HFT) (score=1) [13].
• Bullish for data center infrastructure/HVAC stocks (score=1 each) [13].

No direct link was found between the CyrusOne Aurora data center’s cooling failure and AI workloads [12]. However, the broader industry context highlights AI’s role in increasing cooling challenges:

• AI workloads drive 75% of new data center projects, requiring liquid cooling to handle 2–3x higher heat than traditional workloads [6][8].
• Rack density has doubled since 2021 due to AI/HPC, straining conventional cooling systems [7].

This outage underscores critical infrastructure vulnerability even if not AI-driven—cooling failures can disrupt global markets, and AI’s growth will amplify this risk.

The outage lasted longer than CME’s 2019 technical error [2], supporting the user’s point about potential redundancy gaps. However, the latency argument for HFT is plausible: switching to East Coast backups would increase latency (critical for HFT firms), so CME may prioritize low latency over full failover [13].

CME’s stock did not drop significantly, possibly due to:

• Quick resolution (~10 hours) [3].
• Thanksgiving holiday reducing trading volume/impact [1][10].

a.

: Temporary disruption, but reputational risk if outages become frequent; may lead to increased investment in cooling/redundancy [2][9].
b. : Limited impact due to Thanksgiving, but halted trading for key derivatives (e.g., S&P futures) raised concerns about infrastructure reliability [1][5].
c. : Reinforces demand for advanced cooling (liquid cooling) and redundant systems, benefiting firms like Comfort Systems USA (user point) or liquid cooling providers [6][7].

• CyrusOne Aurora Data Center
  : CME sold the campus to CyrusOne in2016; recent noise complaints over chillers (Chicago Tribune, cited in [12]).
• AI Market Projection
  : AI-optimized data centers to represent 28% of global market by2027 [6].
• CME’s Scale
  : World’s largest derivatives exchange, with outages affecting millions of contracts [2][5].

a. Direct evidence linking the CyrusOne Aurora cooling failure to AI workloads (no search results found).
b. Exact root cause of the cooling failure (e.g., component failure, maintenance gap?).
c. Details of CME’s failover systems: Did they attempt to switch to backup, and why it didn’t work (latency or technical barriers?).
d. Long-term infrastructure investment plans by CME post-outage.