Will the extreme heat be normal?
LAS VEGAS (KTNV)  Las Vegas is one of the fastest warming cities in the u.s, rising on average 5.6 degrees for the summer average temperature. You can see and feel the changes over the years. Last year, we had 158 days where temperatures were more than 90 degrees. Thats 27 degrees above the annual average. So far this year weve hit 57 days and its only the beginning of July. The citys all time high record is 117. RELATED: Excessive heat warning starts Wednesday for Las Vegas area  National Weather Service meteorologist Chelsea Peters explains: "With this heat event in particular and why its more attention grabbing because the probability of reaching that is not a low chance." So were close. There isnt a simple direct cause for the increase in temperatures. There are many atmospheric and climate variables to consider. However, a top source is the urban heat island effect. Development has increased rapidly over the past few decades and is on track to grow. Other cities like Seattle, Denver, Washington D.C and Columbus are sometimes called urban deserts. Well here, we take that in a literal sense. In short, when you remove vegetation and replace it with concrete and asphalt, it causes these areas to absorb more heat instead of reflecting it. This makes urban areas much warmer than surrounding, more rural places. Removing vegetation lowers the amount of shading and water evaporation from soil and leaves. These heat effects can be seen drastically in the rise of warmer temperatures at night in Las Vegas. "What the temperatures are normally for Las Vegas have risen considerably over the past 30 years," Peters told us. The combination of this heat island effect, weather patterns, and the global mean temperature rising all contribute to longer and more intense heat here. This heat in turn has negative impacts like drought and poor air quality which are major issues in Southern Nevada. MORE: Climate change contributing to record-setting heat, drought in Las Vegas  "Climate is knowing that its going to be hot in the summer. The day to day weather and how that weather pattern evolves and how hot it gets is when you are talking about weather. They go hand in hand. The strength of these heat events happening more frequently is definitely a possibility because of the fact that our global temperatures is warming," says Peters. Moms Clean Air Force is a national organization with more than 8 thousands members in Nevada. Their mission is to fight for cleaner air and combat changes in the climate. These moms want to make the community more aware of the dangerous impacts this heat wave can have on families, especially children. Moms Clean Air Force state coordinator Cinthia Moore told us: "Im a mom of a 4 year old. I grew up in Las Vegas and his childhood is completely different than mine." While it was hot when Moore was younger, she says she didnt have to worry so much about breathing issues but her son experiences breathing issues and has problems with the extreme heat.