2/8/09 FCST: TX, OK, KS

[Verne Carlson]

First chase of 2009? (Tornado Alley)

Might be a long shot but the ensembles and GFS are showing some hopes for the first chase of 2009 in Tornado Alley. A cut-off low ejects into west TX on Sunday Feb 8th with some moisture and marginal capes and a surface low in e. NM. Have to see if this develops into anything for us all.

 

[Chad Cowan]

I was thinking about starting this same thread today but figured I'd be called crazy and locked up for a severe case of SDS Here's what I'm seeing...

Pros:
All of the major models and most NAEFS members have converged on an eastern Pacific cutoff low around the middle of the week. The op-GFS and ensemble means have been (surprisingly) consistent in the 180+ hr time frame in scooping up this system into the main flow, stalling a broad trough over the southwest and ejecting 3 or 4 shortwaves into the Plains starting early next weekend. This is definitely the optimal scenario and if it verifies we could be looking at 2-3 chaseable days on the central and southern plains most likely starting Sunday Feb 8.

Cons:
1) The monster east coast trough that sweeps down through the southeast in the early part of this week will absolutely wipe out the Gulf. All the good moisture will be pushed down past Cuba and the Yucatan. If the cutoff low stalls and doesn't eject right away, however, like the Euro has been hinting at, the Gulf will have time the modify enough for some decent moisture to be in place for the event. BUT...

2) The Euro, like the GFS, has been consistent the last few days with the handling of this cutoff energy. With the GFS, the cutoff low gets scooped up into the main flow because of a shortwave dipping down and phasing completely with this energy. The Euro seems to think this shortwave will only partially phase with the cutoff low and this results in the cutoff low energy being dragged through the far southern Plains with a positive tilt and much less favorable trajectory. This solution resembles what the previous system (ice storm) did. In most cases I would put more faith in the Euro than the GFS at this range but each of the past 8 GFS ensemble means have remained consistent with its solution. We probably won't know which long range model has a better grasp on the situation for a few days.

 

[Jim Tang]

If the closed low off the coast of the SW US ejects in pieces (if it even materializes!), then yes, I foresee some type of event in around 10 days. But the chances of that are very, very slim. Any other scenario, and I guarantee you there won't be enough quality moisture.

 

[Matt Gingery]

Both GFS and ECMWF models show the upper trough still in CA on Feb 6, so that's way too early for any substantial severe in US on the 6th. On the 6th the surface trough has a big surface high immediately to its southeast, so the air heading north toward the low will be cool and stable, thats as far as ECMWF goes, however GFS goes past that and shows the upper trough move into the plains for a chance of severe on the 8th, maybe into the 9th. Its a long ways out, and the closer we get to the date the better. I spoke with Ted Keller yesterday and we are tentatively hoping to be able to chase that Sunday. I hope it falls on a weekend so I don't miss work/school.

 

[Darren Addy]

The other factor that comes into this is whether or not Mount Redoubt blows its top, which scientists are saying its imminent, that would play havoc with the weather this season!

I'm not sure how much data there is on this. If you have some links, I'd be interested in seeing them. I realize it is just one data point, but when Mount St. Helens erupted, in May of 1980, the ash plume was circling the world in the jet stream by June 1st. June of 1980 had 217 tornadoes reported. The AVERAGE for June (1950-1999) was 168.

Again, that's just one data point and doesn't necessarily apply to a February eruption and a chase season that begins a full 2-3 months later. But interesting!

 

[Chris Nuttall]

MOD NOTE: I'll leave the thread as it is for now, but if it still appears to be possible next week, this thread will be moved and changed to a FCST thread.

 

[Bobby Prentice]

Not to say its impossible, but severe storms are very rare across west Texas in February:

Centered Feb 05

centered Feb 12

 

[Matt Gingery]

After looking at all the updated forecasts and extended forecasts today from NOAA there is less than a 5% chance of any severe weather. At this time they are only forecasting showers for the Ozarks. This could change, and if there is any chance to chase this coming weekend, it will be across the Arklatex on into Dixie Alley, but I wouldn't hold my breath. Alot will have to change in the models before I get motivated. No worries, it is getting real close to March, and that is when things start heating up.

 

[Matt Gingery]

Originally I was pondering what time of day this action would get started on Sunday. Now, after looking at the forecast synopsis for Sunday, it is definately possible that we see a late afternoon event from Perryton Tx. to Lubbock around 21z on Sunday. We will see. In fact, it is possible that we could see some action into the I-44 corridor from Lawton to OKC as well. The picture will become clearer by Thurs/Fri.

 

[Jim Bishop]

Moisture, or lack there of, is going to be a major issue for Sunday, a day that doesn't look very interesting to me. I'm more interested in the next shortwave that the GFS/European and the Ensembles eject into the Plains next Tue/Wed (Feb 10/11). That system will have more time to advect better low level moisture into the Southern Plains and could cause a severe storm event Tue or Wed.

Whether or not the event is both chaseable and conducive for tornadoes is a whole different story. So let's get timing of the shortwave down first and go from there.

 

[Aaron Dooley]

Hmmm

I never thought the 7th had potential based on moisture alone.

However, I am looking at Sunday into Tuesday morning at this time. Better moisture return, jet, etc.

I think Monday has the highest potential at this time for central TX, north TX, SE OK, & Arkansas. Models have been changing on timing and position last 4 runs of GFS/MRF so it's a hurry up and wait until the 2/9 comes into range of other models.

 

[Michael O'Keeffe]

While we are all looking at the cold bias GFS, I happened to take a look at the NAM, the 18z which goes out to 6z Friday night is showing southerly flow and 50tds trying to reach the Red River, based on that and the fact we will see southerly flow all day Saturday across the S Plains I don't see how we can't get 55tds and maybe temps in the 70s as the GFS is usually cold bias as I have noticed and have been told.

Either way I am more confident on the storm behind it if nothing else. We'll see, but I'm not throwing in the towel until the day before the event.

 

[Matt Gingery]

Moisture, or lack there of, is going to be a major issue for Sunday, a day that doesn't look very interesting to me. I'm more interested in the next shortwave that the GFS/European and the Ensembles eject into the Plains next Tue/Wed (Feb 10/11). That system will have more time to advect better low level moisture into the Southern Plains and could cause a severe storm event Tue or Wed.

Whether or not the event is both chaseable and conducive for tornadoes is a whole different story. So let's get timing of the shortwave down first and go from there.

Yes, I totally agree with you. I noticed that today as well. This system moving in on Sat/Sun could be a player, and I won't count it out just yet. It will become a mature cyclone on Sunday/Monday as it occludes across Kansas/Oklahoma. Moisture will likely show up just in time. I have to say that there will be a shot to chase this weekend. This next trough following behind this one has some question marks as well, and it is a bit early. It looks much the same as this weekends system looked 3 days ago. Only time will tell. I do agree with you that it will also give us a shot. We may be in a short term pattern that will give us a chance to dust off the equipment. I am personally going to plan on chasing Sunday across SW Oklahoma, and N. Central Texas, and I would say its a 30/70 chance at this point.

 

[nickgrillo]

Personally, I haven't been paying much attention given the time of the year and my location (I don't plan on leaving for my chase vacation until the last week of April), but the GFS does show potential for a severe weather event during the 10/11th timeframe. I'm thinking the moisture will be in place this time around given the favorable low-level parcel trajectories off the gulf days prior to the shortwave progged to eject into the southern/central plains. Interesting to see the 50f isodrosotherm all the way north to the MI/IN border. Way too far out, but it's still entertaining to see... IMO, I'm thinking there will be a chase day or two early next week.

 

[Verne Carlson]

Strong forcing but limited moisture and instablilty for sunday makes tornado chances slim but still should see some damaging winds and large hail from Amarillo up to Dodge City. SPC now has this system on the 4-8 day outlook. I will likely chase this day just to get out and brush the dust off the chase gear!