Oklahoma is known for its unruly weather. When weather conditions or other physical conditions present a danger to the participants, the Oklahoma City Memorial Marathon officials maintain the right to cancel the race. Less threatening conditions could cause alteration of the race and/or the race course or length of the race to ensure participant, volunteer and community safety. Such conditions fall under the label “Act of God” – and will not result in refunding of any race entry fee or future race credits.

The Memorial Marathon has contracted with Perry Weather Consultants to monitor our localized venue, at a street-level resolution, for all types of severe weather and any associated risks.  We will monitor the temperature, wind, humidity, wet-bulb temperature, rain, lightning and any form of severe weather and then relay it to you and put it at your fingertips. Since we have experienced one form of weather on one part of the course and sun at another mile marker, this will allow us to communicate the weather along the course as it’s happening. We believe this will offer our runners a unique service that redefines how we look at the weather forecast on Race Day.

The Oklahoma City Memorial Marathon uses the WBGT (wet-bulb globe temperature) index as its standard. High heat and humidity, as measured in accordance with the American College of Sports Medicine recommendations for participation in endurance events could result in cancellation of the event. WBGT is considered ‘the most practical heat stress index characterizing the effect of a heat stress environment on the individual.’ WBGT was developed because the dry-bulb temperature alone does not provide a realistic guide to the effects of heat, as it does not take humidity and heat radiation into consideration. The result of the WBGT will be indicated on a flag system that will be displayed at the start and finish area as well as at the 12 medical stations along the race course. The flag color will indicate the safety conditions based on the WBGT readings. They are as follows:

Alert Level

Event Conditions

Recommended Actions


Event Cancelled
Extreme and Dangerous Conditions

Participation Stopped
Follow OKC Memorial Marathon Official’s Instructions


Potentially Dangerous Conditions

Slow down
Observe course changes, follow OKC Memorial Marathon Official’s Instructions/consider stopping


Less than Ideal Conditions

Slow Down
Be Prepared for Worsening Conditions


Low Risk Good Conditions

Enjoy The Event
Be Alert


No Risk

Enjoy The Event

At the starting line there will be a banner over the street. Suspended from that banner will be 2 flags, each 2’x3’. The flag color will reflect the heat stress at that moment.

Along the course there will be 12 red medical aid (tents) stations. Each medical aid station will be flying a flag of a color corresponding to the heat stress at that time. The flag colors will change within 15 minutes of a change in the heat stress level. The staff at the aid station will know the meaning of each color flag.

Extreme conditions that are high risk already place a burden on community healthcare systems, including emergency medical transportation, as well as hospital emergency room capacity. This burden encroaches on overall community safety and will be recognized as unnecessary and ill-advised scenario of which the Oklahoma City Memorial Marathon officials will not knowingly place the community in any such position.

The Oklahoma City Memorial Marathon asserts that each participant assumes responsibility when entering an event with the potential risks that a marathon presents. All runners should be discerning of their own fitness level in their decision to enter the marathon and associated events. Furthermore, it strongly advises all participants to cooperate with directives given by Oklahoma City Memorial Marathon officials and to assist in ensuring the safety of their fellow participants, particularly when conditions are less than ideal.

As the WBGT rises, so does sweating and fluid losses. With fluid losses comes the risk of various heat injuries; heat cramps, heat exhaustion and heat stroke. It is strongly recommended that all runners slow their pace and reduce their risk to heat stress when conditions warrant. Hydration and misting stations to cool does not prevent heat stress if your pace is not adjusted. With rising WBGT runners should increase their planned intake of fluids. Additionally, salt (in the form of pretzels) will be available on the course. Supplemental salt will help prevent cramps. While runners should increase their fluid intake as the WBGT rises, be careful to avoid excessive water intake and the possibility of overhydration, or hyponatremia, which is the dilution of electrolytes in the blood stream to a dangerous level. Adding salt to your hydration plan will help prevent this.

The Oklahoma City Memorial Marathon offers 22 hydration/water stops on the full marathon course. There are more than adequate amounts to ensure hydration under favorable conditions. If those conditions worsen, additional amounts will be pre-staged and deployed, but it should be reasonable to assume that supplies may not be limitless due to logistical constraints entailed in such a distribution effort.

The Oklahoma City Memorial Marathon is committed to the safety of all of our participants, our volunteers and the community at large.