Steve’s Weather Blog – 08/29/2016

Monday, August 29, 2016

Tropical Depression #9

Let me begin by saying this: there are two other systems that are happening right now (Tropical Depression #8 off of the Carolina Coast and Hurricane Gaston east of Bermuda), which will get adequate attention in my regular weathercasts. That being said …

Tropical Depression #9 formed over the weekend from what was previously known as Invest 99-L. As of this writing, the center of Nine is over the northern coast of Cuba but is difficult to located because of shear that is affecting the system. In fact, the shear from the north has managed to displace most of the deeper convection well to the southeast of the center south of Cuba and over the Isle of Youth. This effect is expected to continue through today and lessen tonight. That means that Nine will have a more conducive environment for intensification.

That word: intensification. That seems to be the crux of the forecast for global models this morning. While the forecast track is a bit more certain as time moves on, the intensity forecast is not. With shear lessening over the storm today, it is possible we’ll see Tropical Storm strength attained (39 mph). Afterwards, we’re in for a couple of days of intensification. The question is: how much?

Dry air is forecast to entrain into the system by the time Wednesday rolls around. This will last a day or two and finally leave Nine alone for the weekend. After that, we’ll be nearing a landfall that is projected east of Apalachicola and north of Tampa. Then Nine should return to the Atlantic and then re-intensify.

My Thoughts

I’ve been observing weather for a long time. Daily. Continuously. And in that time, I’ve seen tropical systems do some strange things.

Last night, a friend of mine commented about the lack of cohesion and accuracy amongst the global models in the forecasting of now-Tropical Depression Nine. We talked about it for a few seconds and then recalled one great truth: there was no storm.

That’s the issue for me this time of year. Seriously. While there are certainly models that forecast pretty accurately when they have a storm to forecast (the GFS and ECWFM, for instance), the vast majority of them cannot even agree from one run to the next. Even the more reliable models have had tremendous issues in the formation of Nine and now, even with it formed, can’t get a grip on the evolution of the storm. Here’s the GFS solution for around midnight on Friday morning … lots of rain into Florida with a weak tropical depression:

So, for the next couple of days, rather than issuing a bunch of confusing (and, as evidenced last week – worthless) model predictions, I’m going to stick with what the NHC is saying and modify it not based on a dozen model projections but rather my gut.

Yes, I know – we’re in trouble!

I have to agree with the idea that Nine will make a turn back to Florida. However, I believe that the storm will probably bump up to at least Category One status (74 mph). At least for a short while. And, as far as the path goes, I believe it may work its way a little farther north than this morning’s official track before turning back to Florida.

In fact, the only sensible effect that Nine will have over the Mississippi Gulf Coast, in my opinion, is heat. With the storm’s proximity in the Gulf, we’ll be victim of west-side subsidence, making us much warmer on Thursday and Friday. And with all that tropical energy would up, most of the moisture that would be in our area … won’t be. No relief from the heat until the weekend.

Those are my thoughts this morning. Please feel free to comment or ask questions … I’m happy to answer if I’m able!

– Meteorologist Steve Taylor