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Ramsey County Multi-Hazard Mitigation Plan, 2018 Page | 86 Extreme Heat History in Ramsey County July is the hottest month on average in St. Paul, with an average high of 83° F. The highest temperature ever recorded there occurred in 1988, when it rose to 105° F (Intellicast, 2018). According to the NCEI, in July of 2015, several observations across Ramsey County measured heat indices over 105° F for two days in a row. The highest heat index value was 116° F. Heat indices of 105° F occurred in August of 2013, during the Minnesota State Fair. 216 people required treatment due to heat-related illnesses. 10 people required transport to local hospitals. Minneapolis schools also cancelled outdoor athletic practices during this period of extreme heat. The following is taken from the 2018 Report: Planning for Climate & Health Impacts in Metro Minnesota: Emergency Management Considerations for HSEM Region 6 (MDH, 2018): Minneapolis experienced its most humid day on record and tied the all-time record for a heat index (119 degrees) during the Extreme Heat Wave of 2011. The magnitude and persistence of high dew point temperatures and heat index values led meteorologists to label the event a “humidity storm”. In the metro area, temperatures soared both day and night – two days hit a maximum 100 degrees and 12 more reached 90 degrees, while a record of 80 degrees was set for nighttime lows. Due to the urban heat island effect, temperatures in the metro region are often higher compared to less urban surrounding areas, usually an average of 2 degrees higher. However, during heat waves this temperature difference can spike to as much as 9 degrees. Ultraviolet (UV) monitoring showed dangerously elevated levels of radiation during the heat wave, which can lead to acute and chronic effects on the skin, eyes, and immune system, including skin cancer and cataracts. The average UV index for July 2011 (9.7) was the highest for any July since 1994. The UV index for days during peak heat intensity were above 10, a level associated with a very high risk of serious health effects. Extreme Heat and Climate Change Minnesota’s average temperature has increased more than 1.5°F since recordkeeping began in 1895, with increased warming happening in recent decades (International Climate Adaptation Team, 2013). Annual temperatures in the Midwest have generally been well above the 1901-1960 average since the late 1990s, with the decade of the 2000s being the warmest on record (Kunkel, et al., 2013). Seven of Minnesota’s 10 warmest years occurred in the last 15 years. Projected increases are 2° F to 6° F more by 2050 and 5° F to 10° F by 2100 (MN Environmental Quality Board, 2014). The Midwest has experienced major heat waves and their frequency has increased over the last 6 decades (Perera, et al., 2012). For the U.S., mortality increases 4% during heat waves compared with non-heat wave days (Anderson & Bell, 2011). Heat stress is projected to increase because of climbing summer temperatures and humidity (Schoof, 2012). On July 19, 2011, Moorhead Minnesota set a new state record for the hottest heat index ever, at 134° F. That same day, Moorhead also recorded a new state record for the highest dew point at 88. It was the hottest, most humid spot on the planet that day (Douglas, 2011). Statistics from NOAA show that there are more human fatalities each year due to heat waves than from floods, lightning, tornadoes and winter storms. Many cities have responded by creating Heat Wave Response Plans to ensure that those in marginal health without air conditioning can obtain the relief and