7/21 – The Chief’s “Hot & Humid” Friday Morning Forecast

The short term is practically a rinse and repeat of the last day or two, with continued hot conditions expected. A HEAT ADVISORY is in effect once again this afternoon with heat indices between 106-112 degrees expected. Synoptically, the region remains under the influence of a large dome of high pressure stretching from California all the way to the Big Bend of Florida. Dry air from subsidence is keeping even most cloud cover development limited much less allowing enough vertical extent for convection. The below average rainfall is helping limiting low level moisture, reducing the heat index values ever so modestly. This has been why our “feels like” temperatures have remained in the Advisory range rather than Excessive Heat Warning Range. This pattern again is projected to continue through the short term, however, there seems to be at least some light at the end of the tunnel…see long term for more details

A pattern change finally begins to take place, which should help reduce the summertime heat just a bit. The ridge aloft will finally begin to retreat just a bit over the Desert Southwest. This will help a weak cold front to move into the region. As the region returns to a northwesterly flow aloft, rain chances, especially with the diurnal cycle will be enhanced. At the surface, a boundary will settle across the region and eventually wash out over the northern Gulf of Mexico by early next week. Low level moisture is forecast to increase ahead of the boundary. The main threat with convection will be localized flooding of urbanized areas. However, a strong wind gust or two will be possible in the stronger updrafts. Temperatures will drop especially over the MS Gulf Coast Sunday and Monday with higher rain chances, but still most locations should reach at least 90F prior to convective initiation.