Tuesday Afternoon Forecast Thoughts

Here's a snapshot of the latest visible satellite imagery from the southeast. Notice we just have scattered clouds across our area, but a better coverage of cloud cover exists in the vicinities of the Texas and Louisiana coastlines. 

Mid-level analysis shows a weak disturbance along the southern MS River area (notice the counter-clockwise circulation around it). It's this feature that's likely contributing to the clouds and showers that are ongoing across the TX/LA coasts. 

Here's 500mb vorticity for tomorrow morning. Notice there's a bullseye right on top of the GTR, and another relative maximum in parts of Arkansas. Normally, I would be lead to believing we could see some organized showers across our area tomorrow, but there are other factors...

First, the pocket of cooler mid-level air, which suggests slightly better lapse rates and buoyancy, is located along and just west of the MS Delta into parts of Arkansas. This may be one of the extra ingredients needed for shower and thunderstorm formation tomorrow along these areas. We could see some isolated showers here as well, but our moisture is low relative to areas to our west. 

We've got a southeasterly to east-southeasterly surface flow which is not bringing in true mT air into our area. However, notice to our west; a southerly flow is pumping copious amounts of gulf moisture needed for rain development. 

The first item of interest over the weekend is the potential Gulf low that is expected to evolve from an area of disturbed weather currently over the western Caribbean. How this interacts with the much-advertised trough will be very interesting. Because we have a trough moving towards us, it's relatively weakening the heights downstream, and this will likely turn this potential tropical system to the north then northeast toward the FL Big Bend. However, it's MUCH too early to be specific on this...

I've been watching this potential system for several days now, and the overall theme is that we'll have a fairly strong trough sweep through the eastern third of the country. However, this morning's run of the GFS actually wants to split this into two separate troughs once it gets closer to our area. I think this might result from the GFS' bias to be too progressive/or too fast to move the energy through the trough. 

Nonetheless, it's looking like a potential interaction between this trough and a potential tropical system. Even if the two don't phase up perfectly, we're looking at increasing rain chances by Saturday night into Sunday in advance of a strong cold front. 

IW