5/29 – Britt’s “Clear” Sunday Evening Forecast

Impulses associated with the weak upper low over the northeast Gulf will work their way westward over the next 48 hours. One will approach the Mississippi coast overnight tonight, with another approaching during the day on Tuesday. Precipitable water values will generally remain near or below an inch over the next few days, but will maximize around 1.5 inches as each of the impulses approaches. These impulses are not likely to produce widespread precipitation, but there`s enough of a threat that brief mentions in the forecast are justified. Land and sea breeze boundaries are likely to serve as a focus, which is likely to reduce any threat to our area. Not much spread in guidance temperatures with readings pretty close to normal, so the only real concern for a temperature bust would be if convection develops just before peak heating. Not enough confidence in that happening in a particular location to make adjustments.

A deep layer ridge axis will be centered over the area on Wednesday and Thursday, but this will be the typical “dirty” ridge we often see during the Summer months. As a result, ample moisture and indicated by precipitable water values of between 1.5 and 1.75 inches will combine with daytime heating to induce ample low level instability. This instability will interact with regions of low level moisture convergence such as seabreeze and outflow boundaries to induce cumulus development during the late morning hours. Some of these cumulus clouds will develop stronger updrafts as the day progresses and temperatures warm into the lower 90s. Eventually, some isolated convection is expected to develop in the mid to late afternoon hours both Wednesday and Thursday afternoons. This low end risk of convection is reflected by PoP values of around 20 percent each day.

The forecast gets a bit more interesting on Friday and Saturday as all of the medium range guidance is in agreement that a low pressure system will move out of the southern and southwestern Gulf of Mexico and toward the eastern Gulf and Florida.  As this system pulls tothe northeast, a weak frontal boundary could be drawn south into the forecast area Friday afternoon and then gradually dissipate over the area on Saturday. Convection could develop along the front as it moves through the region with the highest rain chances occurring in the afternoon hours when the convective temperature of around 90 degrees is reached. By Saturday, the influence of the front will be significantly reduced and a return to more typical widely scattered convection developing along seabreeze and outflow boundaries is expected.

Categories: Weather Headlines