NEW HAVEN, CT (CBSNewYork/AP)Metro-North says trains on the New Haven line are operating at reduced speeds due to high temperatures.

The railroad issued a service advisory Thursday, citing extreme heat and the potential impact on its catenary system as reasons for slow service.

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“Customers should anticipate scattered delays,” said the railroad.

The National Weather Service said the heat index would be at or over 100 degrees Thursday, as it was on Wednesday.

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A high of 96 degrees was reported at Bradley International Airport on Thursday afternoon, matching a 1953 record. A record 97 degrees was reported there Wednesday, breaking a 1995 record of 96.

Cooler weather is expected on Friday, marking the end of the summer’s first heat wave.

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