Email Address

Feel free to email us at
Also follow Brooke and Becky on Twitter
@wxgirlbrooke @wxbecks

Monday, July 11, 2011

Southern Heat Wave and Southwestern Monsoon

As the southwest enjoys the moisture flowing in from the pacific the mid-west, mid-south, and south experience a scorching heat wave. 

Temperatures in the mid-south and south have been anywhere from the mid 90's into the +100, and lets not forget to add in the fact that there is humidity, thanks to the moisture flow from the Gulf of Mexico, bringing the heat index up into the 110+. It doesn't get much better in the evenings either, temperatures may drop down into the mid 80's over night just to heat right back up the next day. The heat is associated with a strong high pressure system positioned over the southern US associated with a stubborn, slow moving warm frontal boundary. Some locations have been getting relief from the scorching heat thanks to thunderstorms firing up along the frontal boundary, however after the storms have moved on the sun peaks back out and the temperature shoots back up with the help of even more humidity present. 

As slow moving as the frontal boundary is it is starting to move easterly and with that relief for the heat is on it's way. A cold front will be moving into the area bringing with it cooler temperatures and a better probability for thunderstorms. 

Below is a image from the water vapor satellite, showing the areas of moisture in the atmosphere. The purple/blue/green indicate moist air and the orange/red indicate dry air. It is a great indicator of where the frontal  boundaries are located along with high/low pressures. Below you can see the large area of high pressure along the gulf coast supplying the south with moisture as well as the gulf coast. 

There is an area of low pressure over northern Texas with a well defined frontal boundary over New Mexico, southern Colorado, all the way into the Ohio valley. Scattered storms are forming along the frontal boundary with a large severe cell moving easterly over Ohio. 

The southwest is experiencing it's monsoon season bringing rain and thundershowers daily. There is a chance of flooding due to the high volume of precipitation in a short amount of time and the dry terrain.  As low pressure systems form off of the west coast and move inland, they are supplying the southwest with the moisture needed for the monsoon season. The unstable air is reaching up into Colorado and Wyoming, supplying that area of the country with the fuel for a tiny monsoon season as well. This is a definite heat relief for the southwest experiencing daily 100+ dry heat days. 

Here is a visual satellite image, complements of Becky, showing the visual cloud cover.

The frontal boundary and scattered storms are visible with little cloud cover over the mid-south helping contribute to the 100+ temperatures. Good news though as the week goes on the heat wave will begin to cool  and the monsoons will continue!

Don't forget it is still hurricane season, but there is currently no activity in the Atlantic or the Pacific.

Hope everyone has a great week and stay safe when it comes to the excessive heat and flash floods!