UPDATED 10:00 a.m. May 18
PJM has issued a Maximum Generation Alert and Load Management Alert for all of Monday, May 18, with hot weather expected throughout the PJM footprint.
The alert is targeted at transmission/generation owners, who then determine if any maintenance or testing on equipment can be deferred or canceled. By deferring maintenance, the units stay online and continue to produce energy that is needed to serve electricity demand, or load, within the PJM region.
Additionally, this alert provides notice to neighboring systems that electricity exports from PJM may be curtailed on May 18. The alert serves as a procedural step that allows those neighboring regions affected to plan accordingly.
PJM issues this alert at the same time as a Load Management Alert, which gives advance notification that load management action may be declared, including non-emergency and emergency Demand Response.
Low Voltage Alert
PJM also has issued Low Voltage Alert for both May 18 and May 19 across its region, which includes 13 states and the District of Columbia. A Low Voltage Alert is an additional precautionary alert that does not require any action from customers.
The alert is issued to heighten awareness and increase planning, analysis and preparation efforts when high demand is expected in upcoming operating periods, allowing transmission owners ample time to coordinate with their distribution companies and take actions to increase voltages resulting in increased transfer capability across the RTO.
A Maintenance Outage Recall is in effect for May 18. The recall requests that all maintenance outages be returned to service by May 18 to increase the amount of generation available to meet customer demand.
Hot Weather Alert
A Hot Weather Alert is in effect for the entire RTO footprint on May 18 and a Hot Weather Alert for May 19 has been expanded to include all PJM zones except the ComEd territory in northern Illinois. A similar alert was issued Monday morning for May 20 in the Mid-Atlantic and Southern zones.*
A Hot Weather Alert is a routine procedure PJM issues ahead of forecasted hot weather and/or high humidity to prepare transmission and generation personnel and facilities for expected increases in electricity demand, or load. This procedure does not require any action from customers.
Temperatures are expected to reach and exceed 90 degrees over the early part of the week, driving increased electricity demand during the heart of the shoulder season, when generation and transmission owners perform maintenance so equipment will be available during peak summer heat in June through August.
Forecasted temperatures for Monday through Wednesday have increased over the last several days, resulting in increases in forecasted electricity demand. PJM will continue to monitor weather forecasts to determine whether to extend or expand any of the emergency procedures already issued and add any additional actions as necessary.
Forecast Peaks
As of May 17, 2026, PJM is expecting to serve the following approximate peak loads on May 18 and 19:
| Date | Forecast Peak Load |
| May 18 | 134,050 MW |
| May 19 | 134,678 MW |
| May 20 | 118,227 MW |
These numbers are official as of 4 p.m. on May 17, 2026. They are subject to change and will be updated periodically.
A dedicated team of operators uses sophisticated technology to balance supply and demand and direct the power grid 24/7 from PJM’s control rooms. They prepare multiple potential scenarios that could be impacted by weather, emergency conditions or equipment failure. They adjust resource output with changes in demand and ensure that no transmission lines or facilities are overloaded. The team also watches for unusual conditions and reacts to them to protect the electricity supply.
PJM will provide operational updates as necessary during the hot weather.
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*NOTE: PJM’s Southern Region is made up of the Dominion transmission zone. The Mid-Atlantic Region is made up of the following transmission zones:
- Atlantic City Electric
- Baltimore Gas and Electric
- Delmarva Power & Light
- Jersey Central Power & Light
- Met-Ed
- Penelec
- PECO Energy
- Pepco
- PPL Electric Utilities
- PSE&G
- Orange & Rockland (Rockland Electric Company)