Small Storm clusters = Tough Forecasts

The local NWS radar at Hammond shows why forecasting this time of year can be tough. Three broken batches of storms show up. The two weaker ones - one on the Southshore and another over Northern St. Tammany into the Bogalusa area - were caused by sea breezes bumping into hot air over land and being forced upward. Once daytime heating is gone — Poof! They are over. But, the one north and west of Baton Rouge, which could threaten this evening’s LSU baseball game, is caused by an upper air system and is therefore likely to persist a few hours after sunset as it moves SE.

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These small clusters with mixed causes will form the theme of this week’s showers. This means that different parts of SE Louisiana and Coastal MS are more likely to get rain on different days. I’ll explain that in my discussion below.

On another topic: Not sure why NWS issued heat advisory today. It briefly reached 94 degrees with a dew point of 72, that’s only slightly warmer than an average summer day with typical humidity. Yes, it’s summer, but nothing unusual.

The Foreca graphic has the right idea with chances of showers every day, more clouds, and a bit cooler afternoon temperatures, but it won’t rain everyday everywhere. Here’s my take:

Scattered showers will break out close to where tonight’s system will die from the River Parishes to roughly Hammond to Folsom and Poplarville. Though some of these will turn into thunderstorms, some with gusty winds, they will have a tough time making it southeast until much later as individual storms will be shunted to the northeast. Meanwhile, a few showers will break out by mid day closer to the New Orleans- Gulfport-Biloxi area because of the sea breeze. In the late afternoon or evening, the storms up north (Hamond-Poplarville) will push to the Lake, Sound, and perhaps even then Southshore. Highs in areas with AM showers will stay in the upper 80s, otherwise it will be almost as hot as today.

Tuesday will see the greatest chance of rain the Southshore, and areas along I-10/12 from Mandeville-Slidell-Biloxi. In fact, the thunderstorms could start at or before dawn and end by mid day. Another scattered batch will develop inland on the Northshore, say from Folsom to Picayune later in the afternoon. High temps. should hold in the mid to upper 80s. Some places could get an inch or two.

Wednesday will see scattered storms, more likely Southshore and St. Tammany Parish - chances pretty much 50-50 and amounts will be less. Thursday will feature more widely scattered showers and storms mostly in the afternoon due to sea breeze activity.

European model features a wet weekend for June 13-15 with lots of Gulf moisture.

Not much to say here….Expecting a fairly dry late June starting about Monday June 16 with about average temperatures. Not expecting any tropical development in the next two weeks. We could go into the second week of August before we see one —but that’s not unusual. Watching hurricane season is like watching the Saints: You never know when they’ll blow the lead in the fourth quarter.

Foreca graphic for Pensacola Beach shows that the lovely beach weather is ending. First, it’s the winds, surf, and rip currents through Tuesday, then storms likely on Wednesday, then a few days of cloudier weather (though not bad), then the rains arrive for next weekend. Oh well, temperatures will be a few degrees cooler there with a nice sea breeze and the second half of June should be lovely.