12/15 – Brantly’s “Mostly Cloudy” Tuesday Morning Forecast
A mid/upper level shortwave trough will traverse the Plains today, reaching the ArkLaTex region by late tonight into early Wednesday morning. Zonal flow will then take hold aloft over the northern Gulf coast as this feature passes to the east late Wednesday afternoon. Through the day today, the region will be under the influence of surface high pressure, which will be centered over the Great Lakes, Upper
Mississippi Valley, and Ohio Valley. A surface low pressure system will develop off the southeastern coast of Texas late this afternoon and begin to progress eastward over the northern Gulf. This low will quickly move over the AL and western FL Panhandle Gulf waters from late tonight through early Wednesday afternoon, with high pressure building in over the region behind it.
Moderate cold air advection will persist early this morning. With low-level moisture still in place along with layer-lifting in the wake of the cold front, the low-level stratus cloud deck continues primarily over southeast MS, while southwest AL, south-central AL, and the western FL Panhandle have seen the low clouds gradually erode from east to west. Although, it has not and will not clear out entirely, since cirrus clouds continue to pass overhead. Low clouds will then gradually increase once again through the day today and overnight tonight. Northerly to northeasterly flow will continue through today, becoming light and variable in the afternoon as a surface ridge settles over the area. As the mid/upper level shortwave trough and surface low approach from the west, a gradual increase in southerly flow will occur tonight.
Precipitation chances will also increase by this evening, becoming likely to definite across much of the area by late tonight. Rain chances will then quickly decrease from west to east through the day on Wednesday as the system progresses to the east, with dry conditions expected by late Wednesday afternoon. In terms of any thunderstorms, although shear will be abundant, upper level dynamics continue to be out of phase and instability remains meager at best. Therefore, no severe weather is expected, but maintained a slight chance of thunderstorms over the open Gulf waters late tonight through Wednesday morning.
High temperatures today are expected to be in the mid 50s to lower 60s, with lows tonight in the mid to upper 40s north of I-10 and in the upper 40s to lower 50s south. Highs Wednesday will then generally be in the mid 50s to lower 60s inland and in the mid to upper 60s near the coast.