Heat is the number one weather killer in the United States. Do I have your attention? Heat kills many more people each year than tornadoes, hurricanes, flooding and lightning. On average, extreme heat will kill 130 Americans per year. Here in Minnesota, we reach 90 degrees an average of 14 times per summer.

Smoke from wildfires often affects our air quality here in Minnesota. Some of the time, a westerly wind will blow smoke toward the state from California or the Pacific Northwest. Other times, an otherwise refreshing northerly breeze will blow Canadian wildfire smoke our way. Most of the time, the smoke is several hundred or even several thousand feet in the air, but we also see ground level smoke and haze, which causes breathing problems for many.

Here at 5 EYEWITNESS NEWS, we'll cover the key flooding concerns along major rivers. For those curious about general information regarding hydrological outlooks, the National Weather Service can be a great source, to provide specific forecasts for varing locations.

During floods, stay informed, listen to any evacuation orders and avoid flooded waters. If you can, get to higher ground. After a flood, wait to go back to flooded areas until it is OK to do so. Pay attention to signage and road closures. One thing that is also important, according to the NWS, is to not use "a portable generator inside your home or garage" as carbon monoxide poisoning is one of the leading causes of deaths after storms.

Tornadoes have occurred in Minnesota every month except December, January and February. Tornado season is mainly late March to mid-October, with the highest frequency of tornadoes from late April through mid-September. The most likely time for tornadoes is May, June, July and August. A tornado is defined as a rapidly rotating column of air that is connected to a thunderstorm cloud and the ground. A funnel cloud is similar to a tornado but has not made contact with the ground, however, it has the chance of becoming a tornado.

Tornadoes are rated on the Enhance Fujita Scale which determines the wind speed of the tornado through a damage assessment from the National Weather Service.

Enhanced Fujita Scale (EF)

EF 0 65 to 85 mph:Light damage mainly to vegetation and loosely-secured ground objects

EF 1 - 86 to 110 mph: Moderate damage to trees and roofs

EF 2 - 111 to 135 mph: Considerable damage to trees, homes and buildings

EF 3 - 136 to 165 mph: Severe damage to trees, homes, buildings and most structures

EF 4 - 166 to 200 mph:Devastating damage to all things above ground

EF 5 - Over 200 mph: Incredible damage to all things, can strip bark off trees and remove pavement down to the soil

Most Minnesota tornadoes are in the EF 0 to EF 1 range with a few EF 2 and EF 3 tornadoes every year, but EF 4 and EF 5 tornadoes occur occasionally, too.

Most Minnesota tornadoes occur in an area from Mankato, south to Iowa, and west to South Dakota. This region is part of Tornado Alley, which stretches south through Nebraska, Iowa, Kansas, Missouri, Oklahoma and Texas. Most of the tornadoes in the world occur in Tornado Alley. The risk for tornadoes decreases north and east of Brainerd and tornadoes are very rare near Lake Superior.

Tornadoes can be easy to see if the tornado is to the north of you but very difficult to see if the tornado is rain-wrapped, meaning heavy rain is obscuring the tornado. Tornadoes mostly occur between 4 p.m. and 8 p.m. but can occur at any hour of the day. Often, a tornado moving toward you will appear black as the dense clouds of the tornado produce thunderstorms that block the sun. A tornado moving away will appear white due to the sun shining on the back side of the tornado. Rainbows are frequently observed behind tornadoes as well. The sky will sometimes turn green ahead of a tornado because of sun rays refracting off hail/ice