More Heat, Isolated Rains Through Thursday

By Jay Grymes & Steve Caparotta

The heat and humidity made for another uncomfortably hot day on Tuesday, and only a few neighborhoods were lucky enough to get some mid-afternoon cooling showers to break the stifling air!  Tuesday’s Heat Index for Metro Airport was already at 95° by 9AM and climbed above 100°before 11AM!

We’ve seen some locally-heavy rains in and around metro New Orleans today, prompting some NWS advisories, but only very limited action anywhere along and north of the I-10/12 corridor as of 4PM.

And we’re expecting a repeat of today’s weather pattern for both Wednesday and Thursday around metro Baton Rouge: morning minimums in the mid to upper 70°s, afternoon highs in the low to mid 90°s, Heat Index readings at or above 100° for upwards of 5-6 hours or more, and only a handful of communities getting an afternoon rain.  For now, we’re calling for no better than a 20% rain chance for the next two days.

A weak and dissipating quasi-stationary front will continue to linger over the Bayou State for the next two days.  Although our afternoon conditions will be hot-and-humid, this weak front will not provide any significant additional lift to get more widespread rains going.

All that changes towards week’s end, however, as another cool front will sag southward and into Louisiana.  Our early guidance suggests that the weekend frontal boundary will have at least some chance of pushing through most or all of Louisiana before dissipating early next week.  But this slow-mover will take its time crossing the state, and that will mean improved rain chances from Friday, through the weekend, and even into Monday.

We’ll have to keep an eye on this developing weather set-up:  while it is far too soon to become concerned as yet, this scenario has some potential to be a fairly serious rainmaker over a 4-5 day period.

And in the tropics?  Remnants of T.D. #7 are moving inland over Honduras and Nicaragua this afternoon and evening, leaving no chance for re-development for this tropical wave.  Still, it is likely to be dump copious amounts of rain and produce flooding for portions of Central America.  And in the central Atlantic, roughly 850 miles southeast of Bermuda, a low-pressure area appears to be getting better organized.  The National Hurricane Center has “upped” its chances for tropical development in the next 48 hours to about 50-50 as it continues to move NW or WNW.  But all the early tropical guidance for this system has it getting caught in the Westerlies (West-to-East flow in the mid-latitudes) over the next couple of days, which means no threat to Bermuda or the U.S. East Coast.