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NYISO peak demand history

See NYISO's highest observed hourly demand each day, when it occurred, and how complete the record is. Inspect annual and seasonal records, separately labeled hourly forecasts, same-season year-earlier comparisons and all seven organized markets on one common UTC day.

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About this view

Read the peak hour

Demand is an hourly average in MW. Each daily peak is the largest observed hourly value on that market's local calendar date, with the hour-beginning timestamp and time zone shown. It differs from an instantaneous operator record or a forecast peak.

Coverage before record claims

Record tables use all retained canonical hourly history through the selected date; the recent daily chart shows 400 days. Missing or null hours remain gaps and can hide a higher peak. The displayed maximum is the highest observed in that retained history; with gaps it is a lower bound.

Same-season historical comparison

Observed 30-day maxima remain visible when coverage is incomplete, labeled as lower bounds. Both windows need every expected hour before a comparable percentage change is shown. The prior window ends on the same calendar date a year earlier; February 29 maps to February 28. Historical values use the latest retained revisions.

System measurement and footprint

NYISO system demand is derived from the sum of eleven published load zones. It is the integrated hourly measurement.

Questions

Is this the official all-time demand record?

It is the highest observed hourly average in the retained hourly history through the selected date. Annual and seasonal rows retain explicit bounds and coverage. It is not an all-time or instantaneous record. Missing hours may hide a higher observation.

Why is a historical change sometimes blank?

The latest and year-earlier 30-day windows each need all expected hourly values. A missing or null hour, an open day or unavailable history withholds the comparable change. Observed period maxima remain visible as lower bounds with their coverage.

How are daylight saving days handled?

Expected hours follow the market's local calendar. A spring transition has 23 hours and an autumn transition has 25. Repeated local hours remain distinct UTC intervals, with the local zone printed beside the peak.

Related views

forecastNYISO load forecastRead the operator outlook separately from historical observations.catalogNYISO Hourly Actual LoadThe underlying table, its schema, and its history.catalogLoad ForecastThe underlying table, its schema, and its history.

More NYISO views

The same view in other markets

Sources

NYISO hourly demand