12/17 – Rob’s “Changes Ahead” Friday Morning Forecast
An upper level high-pressure centered near south Florida expands from east of the Bahamas to the western Gulf of Mexico. Models show a plume of moisture on the western side of that ridge rotating north and into the area today. Isolated to scattered showers will then persist the rest of the evening and overnight hours as moisture remains in place but loss of daytime heating limits convective potential.
Rolling into Saturday, an upper level disturbance will be racing across the Northern Plains and upper Mississippi Valley. A cold front associated will be moving into the area late in the afternoon Saturday and pushing into the coastal waters through the overnight period. There could be some stronger to possibly severe storms on the leading edge of the boundary as it moves into southwest Mississippi and western LA parishes. Models generally indicate stronger storms steadily weakening as they move through the area.
Monday begins with a upper level low moving through TX and into the region. There is disagreement on the strength of the system in the guidance. The associated surface low is expected to track through the Gulf. While there is an increase in rain potential when the system is expected to move in, this system primarily looks to be an isolated rain event. After the system moves through the region, the overall pattern shift to a northerly flow in the upper and lower levels. While the flow does shift more to a northwesterly pattern on Thursday the cold and drier air advection does help decrease the rain chances and bring back standard high pressure conditions.