An Arizona Summer Phenomenon
Information on Monsoon - Sedona, AZ - First of all, there is no need to add season at the end of Monsoon because Monsoon is a season. Monsoon affects the west and southwest states because the pattern of the weather changes as noted below.
How Long Is The Monsoon In Arizona?
Monsoon officially starts on June 15th and ends on September 30th. However most of the rain comes from the middle of July through the middle of August. This is one of the reasons that the Temps in Sedona are a less harsh during July and August. The average rainfall in the state of Arizona is around 12.5 inches. The Sedona area gets more than the average rainfall. We have had as much as 26 inches (2016) and as low as 13.66 inches (2014). See the actual precipitation chart on Sedona-Weather.com.
What Creates Monsoon Conditions?
Weather enthusiasts and forecasters look to the dew point to tell if monsoon conditions exist. The dew point must be about 55º for thunderheads to start development. The dew point indicates how much moisture is in the air. At this point, the air cannot hold water in gas form and the gas will then turn to liquid form creating water droplets. The water droplets create fog or precipitation. Prior to officially declaring a calendar season for monsoon, the season would be declared when there were three days at a dew point of 55º.
2016 - Record Rain Totals
In 2016, the monsoon had 9.65 inches of rain recorded on my station. When you couple that with over 7 inches of rain and 7.5 inches of snow, we had a year end total of 25.92 inches of precipitation.
So Far In 2018...
We started 2018 with 3.73 inches of rainfall in the first two months, but our rainfall is only 4.84 through May. Since 2010, our backyard weather station has recorded an average of 5.8 inches of rain in July and August combined, so we are looking forward to monsoon.
Preparation For Monsoon
One quick note - Because it is our rainy season and the chance of lightning during a thunderstorm could knock out power, take some time to have things ready to go:
- Know where the flashlights and candles are for easy access.
- Keep your cell phone charged
- Clean out gutters - drains - culverts - rain ditches and any other natural path water may take during a sudden downpour.
What Is Monsoon?
It seems that Southern Arizona, the White Mountains and the Phoenix metropolitan area known as "The Valley" get the brunt of the monsoon affects. It is amazing to see the haboob (desert wind storms) kick up and tower thousands of feet in the air moving through the valley. Those storms are the pre-cursor to the rain and massive storm cells that develop from the moisture in the warm air coming off the Gulf of Mexico. Generally, massive amounts of rain falling create downdrafts that push the air out from the center of the storm which produces a dry wind that kicks up the dust and dirt.
During summer, weather patterns change. Storms that travel from the arctic (Alaska) down through Canada and the lower 48, create our winter storm pattern. In the summer, the pattern shifts to the south. Hurricanes, storms and moisture travel northwest from the Gulf of Mexico through Mexico, Texas, New Mexico and Arizona moving all the way to California. We also get moisture coming from the Gulf of California traveling directly north. Lots of moisture and an occasional hurricane come up from the coast of Baja California and push northeast into Arizona.
Up in Northern Arizona, we get a lot of cloud cover and the storms move through but usually don't drop a lot of rain here in Sedona.Though in Flagstaff it is quite a different story! The area of Sedona seems to be protected. By that I mean that most of the rain falls elsewhere before it gets to our little city. But when we do get rain and storm cells, it is a big deal around here. In 2014, Sedona got 7.73 inches of rain from July thru September. In 2013, there was 8.18 inches of rain in the same time frame. Flash flooding can happen because many of the streets are sloped leading up to the red rocks. There has been much improvement made in our drainage system to be able to handle the additional water flow but during an intense storm there is no place for the water to go and mud and rocks can travel across roads to find the path of least resistance. Do not travel through a road where water is more than 4 inches deep. A car can be swept away easily.
Southern & Central Arizona
In Southern and Central Arizona - 2014 will be remembered as the "Monsoon of the Century". All future monsoon activity will be measured in terms of 2014. There were 3 major hurricanes that effected the weather in the southern half of the state. This caused a deluge and many towns and neighborhoods suffered tremendous flooding damage due to flash floods, hurricane wind, broken canals, and water that had no where to go. Many long-time residents had never seen a deluge like we had that year. Sky Harbor Airport had record rainfall of 1.59 inches and has exceeded the all-time record set back in 1903.
Discover more about Sedona Weather
Some of the most incredible pictures are taken during Monsoon
Thunderheads Surround Sedona
89A - West Sedona AZ - looking south
Massive Thunderstorm at Sunset creates Fire In the Sky
North View - Century Plant in Bloom
Cathedral Rock at Monsoon Sunset
Looking Toward the Mogollon Rim
Rare Monsoon Sunset Rainbow
It was taken just a couple of minutes before the sky went on fire!
see original post at http://sellsedona.com/monsoon/