Waffle house has just closed 365 restaurant locations across the U.S. due to the SARS-CoV-2 (coronovirus, COVID-19) pandemic that is sweeping the world. The breakfast-chain announced the news Tuesday via their facebook page.

Why is that a bad thing?

"If you get there and the Waffle House is closed? That's really bad..." Says Craig Fugate, the former head of FEMA.  The Waffle House Index is an informal metric measurment named after the Waffle House restaurant chain and is used by the Federal Emergency Management Agency (FEMA) to determine the effect of a storm or emergency and the likely scale of assistance required for the disaster recovery.

The Measure is based on the reputation of Waffle House for having a great disaster preparedness and staying open during extreme weather, or reopening quickly afterwards.

What are the levels in the Waffle House Index?

Wikipedia states The index has three levels, based on the extent of operations and service at the restaurant following a storm:

• GREEN: full menu – restaurant has power and damage is limited or no damage at all.
• YELLOW: limited menu – no power or only power from a generator, or food supplies may be low.
• RED: the restaurant is closed – indicating severe damage or severe flooding.

The term was coined by FEMA Administrator Craig Fugate in May 2011, following the 2011 Joplin tornado, during which the two Waffle House restaurants in Joplin remained open.

The measure is based on the reputation of the restaurant chain Waffle House for staying open during extreme weather and for reopening quickly, albeit sometimes with a limited menu, after very severe weather events such as tornadoes or hurricanes; for example, assembling and training "Waffle House jump teams" to facilitate fast reopening after disasters. Waffle House, along with other chains (such as Home Depot, Walmart, and Lowe's) which do a significant proportion of their business in the southern US where there is a frequent risk of hurricanes, have good risk management and disaster preparedness. Because of this, and the fact that a cut-down menu is prepared for times when there is no power or limited supplies, the Waffle House Index rarely reaches the red level.

The Waffle House Index sits alongside more formal measures of wind, rainfall, and other weather information, such as the Saffir–Simpson Hurricane Scale, which are used to indicate the intensity of a storm.

In a world of uncertainty and with a rapidly expanding pandemic this is just one more statistic to add to the pile, which is sure to grow even larger.