Looking Down to Dixie

This bright morning sun streaming through the sliding door of my balcony is blinding. At quarter-to-ten on the day before Thanksgiving, it shines low over the southeast horizon directly onto my face, forcing me to write with my left eye shut. That is not an altogether satisfying modus operandi, but I don't feel like closing the blinds or wearing a ... well, what the hell, why not wear a hat? I've just put on my trusty Tilley. Problem solved, though Lisa will probably look at me oddly when she steps into the room. Here in West Michigan, we're moving into high pressure and a warming trend through the holiday. But "warm" is a relative word which in this case means not terribly cold--rather nice, really--but don't plan on wearing a T-shirt. Hundreds of miles to my south, though, warm means warm. Warm enough to get the job done for convective weather. From now through April, Dixie Alley once again becomes the star of the show. The trough moving in for the weekend offers a good example of why. It's a deep trough, and a surface low up in the Great Lakes looks to wick up enough moisture into the Southeast to stoke the storm machine. I've included a couple of the latest 00Z Euro/GFS comparisons plus Euro 850 mb relative humidity to give you a sense of what's shaping up for 96 hours (click on images to enlarge them). The GFS is predictably faster than the ECMWF, but both are pointing to the same overall scenario, with the trough eventually pinching off into a closed low. Cloud cover presently looks like it will be rampant, minimizing instability. Still, given some ripping bulk shear, this system is something to keep an eye on as it evolves, particularly if you live in Dixie Alley. That's all for now. The sun has moved and is no longer blinding me. Time to get on with the rest of this day. May you and yours enjoy a happy and blessed Thanksgiving!

Tomorrow’s Chase Scenario

If I were to pick a chase target for tomorrow, it would be Rolla, Missouri. That's based on a sampling of the 6Z model soundings of the GFS, NCEP's present model preference. Frankly, though, I can't get too excited about this system. True, it seems to be shifting the activity to within striking distance, where I could conceivably go chasing and still make it back Friday morning in time to make an appointment that I absolutely can't miss. But instability isn't all that great, and besides, who wants to go chasing in Missouri hill country? If the NAM verifies, things will shift north a bit. But I don't see that making a practical difference. It's a marginal setup at this point, and unless things improve, I don't think I'll feel short-changed sitting this round out. Maybe the next trough will be an improvement. ADDENDUM: Ouch! Just looked at the SPC's afternoon update. If they're right, then only the desperate and the insane will be chasing tomorrow. They've pulled the 30 percent risk down mostly into Arkansas, tapping on southeast Oklahoma, northeast Texas, and extreme southern Missouri down around Branson. Anyone for a chase through the Ozarks?

Crystal Ball Gazing with the GFS

Yesterday's trough passed through pretty much as expected, without a whole lot of fanfare and certainly not with anything tornadic. So the question is, what lies ahead? Anything? Maybe. At least we're not locking in under another ridge. Today is the first day of autumn, the weather patterns are changing, and the GFS and ECMWF seem to agree on a 500 mb trough affecting the Midwest over the next several days. And yeah, yeah, I know it's just reading tea leaves, but here are a couple 132-hour GFS maps for next Sunday at 00Z. At the risk of stating the obvious, click on the images to enlarge them. The first shows sea level pressure (shaded), surface wind barbs, and 500 mb height contours. The second map shows 500 mb winds (shaded) with wind barbs, and 300 mb wind contours. The big question mark may be moisture. But this far out, it'll be nice if that even matters by the time Sunday arrives. This time of year, living in the Great Lakes, the best one can do is hope. But there's nothing wrong with hoping.

Next Week: Troughing in the Picture?

I'm prepared to get my hopes up a bit. The ECMWF and GFS both now appear to agree on a trough working its way through the country's mid-section. Here's the current GFS for 21Z Sunday afternoon:

GFS Sea Level Pressure for 21Z Sunday.

GFS Sea Level Pressure for 21Z Sunday.

Granted, there's a lot more that needs to happen, such as mid-level winds and moisture connecting, but this will do for starters. It's a better picture than yesterday.

The GFS wants to move this system through faster than the ECMWF, but at the moment I'm not going to worry my head about it. All I care about right now is, both forecast models are pointing to a bit of troughiness taking shape. It's something to keep an eye on. Fingers remain crossed, and while I'm still not holding my breath, I'm hoping that the next few days will offer some reasons to do so.