While most television meteorologists are not talking about it yet, there are some early indications that next week may be very hot and humid for most parts of the Southeast. By Sunday, June 14, extended range forecasts indicate that a dome of high pressure may move into the region, causing relatively dry conditions and very warm temperatures in the region. The high pressure is also expected to direct a stream of tropical moisture into Louisiana, Arkansas and eastern Texas, potentially contributing to more heavy rains in that area. Heat waves in the Southeast have frequently been observed in El Nino summers, so this is not unexpected.
The maps below show the expected 10-day precipitation accumulation from the GFS forecast model and the precipitable water departure from expected conditions. The green “hole” in the accumulated precipitation indicates that rainfall, while possible, is less likely than areas away from the center of high pressure. “Precipitable water” is a measure of how much moisture there is in the vertical column of the atmosphere which is potentially available to make precipitation in the form of rain or snow. The map shows the stream of moist air moving up into areas to our west on June 14.
Remember, long-term forecasts have a lot of uncertainty, so you will want to keep an eye on updated forecasts to make sure you know what weather to prepare for.
If you need help getting ready for extreme heat events, please visit my blog posting from earlier this week at https://site.extension.uga.edu/climate/2015/06/national-weather-service-and-eden-heat-safety-information/.
