5/25/09 FCST: TX/OK PHs

[Jason Persoff]

Geez...Looking at the GFS and NAM, it's as if someone sprayed jetstream repellant over the whole of the US Plains. Just north and south of the US borders there are jets. That they are mirror opposites in their wave phase only adds to the feeling that the jetstreams are trying hard to avoid touching the US.

So, Monday...The GFS and the NAM are both showing the same gist.

At the surface a sharply delineated dryline will set up over the Cap Rock area, with Tds in advance of the line >55 deg. The dryline will develop a bit of a bulge around the AMA area. Sfc temps could near 100 deg. A low is forecast to form over NM and push out into the TX PH. Upper level divergent flow regime will be aided by an upper low pressure system over Baja. But that "aid" is merely to add a touch of buoyancy to an awful flow with 200mb winds barely exceeding 30kts out of the WSW and some "impulse-ish" 35kt WNW flow at 500mb. There will be rotational shear with height, but it's not a nice looking hodograph over the LBB to AMA area (sfc ESE at 10+, 850mb SSE, 700mb WNW, 500mb WNW, 200mb WSW). There won't be a lot of CAPE (AOA 1000 J/Kg). Tc should be surmountable from daytime heating, a lack of cloud cover, and the dryline. UVV forecast to be good, but mixing ratios are absolutely dismal.

It's hard for me to look at this forecast and feel enthusiasm. Current models suggest this is almost too borderline even to hope for Caprock magic. I sit flabbergasted at the year that isn't. When I saw that the 4-8 day outlook was a mere 3 sentences this morning, I bowed my head in mourning.

I've already began to explore the costs of changing my reservation to fly back to FL and turn in my car rental a week early. It's a good cost-saving maneuver given the situation...I laugh a bit: thus far this year, I've shot a total of 2 pictures and 30secs of pea-sized hail video. That's it.

 

[Jay McCoy]

Temps in the panhandle wont even come close to 100 on Monday.

 

[Sam Hall]

I couldn't agree more... we come here annually from the UK and have never seen such a weirdly dismal pattern. What IS it with that jet? We only have two weeks left before we have to fly home I am seriously hoping it'll change drastically. At the moment, I'd be happy with anything - even just some rain!

A BIT of convergence over the central plains, but as you say ETA progging absolutely awful wind profiles, OK directions in a way but dismal strengths. Just as the 700 temps become a bit more likeable everything else dies too.

72-hr ETA has up to 1500 J/kg CAPE in central parts of KS, NE and around... almost following the kind of dryline - I say kind of, because it's not really is it! I'm not seeing the 100 temps, other than far south, ETA (again 72 hr at this time) progging around 80 Ts for KS/NE areas. A small blob of 70s DPs in E/CTR to S SD. If everything else was nice, this would be quite good for bringing bases to a nicer level than of recent pathetic attempts of stormy conditions. Winds veering in SD/ND with slightly better strengths but nothing else.

It's just like it just does not want to DO anything. This is getting frustrating. We have already driven 3300 miles in a week and seen two storms. This is actually now officially worse than the death ridge of 2006 IMHO.

 

[Angie Norris]

Maybe it's my imagination, maybe it's wishful thinking, but things look somewhat interesting in the southern Panhandle for tomorrow.

There's a small CAPE spike of about 1500J/kg showing in the vicinity of Plainview at 0Z, along with a bit of a dryline bulge. Granted, it looks like it's a fair distance off the triple point with the surface low up in NE NM, and granted the wind fields are PATHETIC...20kts at 500mb(?!?!?!?) and surface winds of 5-10kts, but there is some decent directional shear. 850 temps are progged in the upper teens, so maybe the cap won't be an issue for once.

A nice, photogenic storm would be sweet (but I sure wouldn't turn down a nader if Mom Nature wants to be generous!). Hopefully things will look good on tomorrow morning's RUC.

 

[Andrew Butler]

ND, SD And MN should probably be added to this. There is actually some decent directional shear centered in northwest MN/eastern ND along with "better" upper support and if enough instability were to come into the picture tomorrow we could have a supercell or two.

Forecast soundings in the Morris to Fargo area are not too shabby, except for real good instability. Any other year we'd be laughing at this but we take what we can get in 09 I guess...

 

[Sam Hall]

We are having a driving day tomorrow to head towards OK for Tue/Weds maybe. Better wind profiles 300-850 mb and some CAPE and better dews...

 

[Angie Norris]

Well, it's not looking that good.
12Z RUC is showing the weak winds, but at least there is some directional shear. CAPE is progged over the south central Panhandle to be in the 1500J/kg range. Dewpoint spreads indicate high based storms, and AMA's sounding is showing precipitable water of 1.10". It would be nice to see a decent dryline so we'd have something to focus convection on, but I'm not seeing it. Basically, it looks like it's going to be high based popcorn storms that are going to drop a ton of rain and maybe marginally severe hail.
If I decide to head out, Pampa is my target.

 

[Scott Olson]

I agree with Andrew. South Dakota/North Dakota/Minnesota are going to be the more viable play today. First what we have going for us, we have 1000-1500 j/kg of MLCAPE, with decent shear in the 0-3km layer (of about 20kts). Unlike yesterday in Nebraska we have much more noted lift/upper support, slightly more instability and have somewhat stronger winds at 700mb. MLLCL's remain doable between 1000-1300m. Now for what we don't have going for us. We have non-existent winds above 700mb. Which means that the storms will tend to vent into the updrafts of other storms. And since the CIN remains very weak, it's likely the whole front (or behind the front) will go up and make it very hard for a sustained updraft. The 0-6km shear is on the same magnitude as the 0-3km shear, owing to the awful mid and upper level winds. The freezing level is quite high, at around 12,000 feet or so and with the lower end of moderate instability I'd think large hail is nary of a concern.

I can envision two scenarios, first that something manages to go earlier, say 18z. Being a single storm in this kind of setup wouldn't be so bad and would probably give a reasonably interesting storm. Next there is plenty of differential heating that might serve to enhance low level vorticity. Third, as with yesterday in Nebraska. There is decent 0-3km CAPE of around 100 j/kg and should be some areas along the front and along any differential boundaries or outflow boundaries from other storms where verticla vorticity is maximized and with all the updrafts all around would present the possibility for at least a landspout or two. That seems the most we can hope for when the upper support is so poor as it is right now.

/Whispers to the Wind/
Scott.

 

[Warren Faidley]

Target for today: Pampa, Texas to Liberal, KS. Nothing too exciting today, so will play the "Pampa Triangle" zone where mysterious things can, and occasionally do occur. RUC 21z forecasted CAPE and what might be some surface veering looks best in this region. I also like the fact that there **might** be a weak boundary in this area from yesterday's activity. LCL's pose an issue everywhere, but slightly more further SE towards Childress, especially if storms drift E/NE into Oklahoma. Best pressure falls and backing winds ATM also support a Pampa or N-NE areas. TCUN profiler seems to suggest best upper level flow (what little there is) will be over the Pampa Triangle. (Also showing lowering + flow, although too early to see if this is a positive trend). It's not a great chase day, but there might be one diamond in the mix.

Good luck to all and thanks to our troops on Memorial day.

W.

 

[Jason Boggs]

As of right now,I'm thinking of targeting the area of Clarendon, TX. I think this area will be the best bet today with the higher CAPE. Without the good dynamics, setups like today are best where there is the best mixture of T and Td for the best instability.

The tornado chances today are pretty small, but maybe the larger CAPE values can at least give us some supercell structures. I'm just looking to play in the hail and maybe at least get a lowering or two. I think a T-storm watch may be issued, and I bet the SPC goes slight on the next outlook.