Sunday, 22 March 2009

USA Storm chances - Mon 23rd March

After a fair while without severe weather, the central Plains of the USA look set to receive some on Monday. An approaching upper trough should promote lee cyclogenesis and set the stage for thunderstorms, some severe, on Monday afternoon and evening.

Whilst moisture is not going to be plentiful, there looks like there will be enough for some severe weather. Dewpoints in the 50s F are already across much of Texas and Oklahoma, with 60s dews arriving on the southern Gulf coast. Another 24 hours of return flow should deepen the moist sector. The upper system will serve to steepen lapse rates as it moves in through the day.
The best compromise of ingredients and shear appears to be, to me, over central and northern Oklahoma on Monday afternoon. The dry line looks like stalling through the area, although will be overtaken by the cold front overnight. Supercells seem likely to develop along the dry line and the propogate into the moist sector - WRF seems to indicate the chance of long-lived supercells/supercell clusters through the evening, moving from west-central OK north-eastwards to the OK/KS border around I-35. If chasing, you would want to get ahead of these cells as the cells will be moving quite fast.

High shear-limited moisture set-ups often lead to storms leaning towards the LP end of the spectrum, bringing the risk of large hail and high winds. However, moisture pooling could locally enhance tornado potential. Analysis through the day on Monday will help pin down the regions most at risk.

Wednesday, 18 March 2009

Speed and things

I'm always amazed at the number of motorists who seemingly fail to 'get' what average speed cameras actually are. I've noted dozens of people braking hard as the pass the first camera, only to speed up again through the road works, and then slow down again at the next one! Confounded baffoons the lot of them!!

And another thing - motorists in Reading seem to have taken it upon themselves to 'tag slow drive' when I'm on the road. Now, I don't want to hammer around everywhere, just doing the standard 30mph through town is perfectly fine. But following some dawdler ambling along at 20mph is just sooo annoying! And just when the offender pulls into a side road, another seems to be 'tagged' and pulls out in front of me! And why does it take so long for people to pull away from traffic lights? Do people see them change so much more slowly than I do?! Doh.

Thursday, 12 March 2009

Storm chase review - 29th May 2008 - Nebraska

I thought I'd post a video of the intense supercell which affected portions of south-central Nebraska on May 29th 2008. We started our chase day in Salina, Kansas. The SPC had issued a high risk of severe thunderstorms for parts of Nebraska and Iowa, mentioning the risk of strong, long track tornadoes. Our initial target was Red Cloud, Nebraska. I wanted to pick up the southernmost storm (the 'tail-end Charlie'), as this would have the best moisture amd would be unaffected by other storms.

However, once in Red Cloud, we noted a storm developing to our west, near McCook, Nebraska. We headed west and then north, and made our intercept to the west of Kearney. We had to punch northwards through the RFD, and encountered severe winds south of Odessa. We made it through the RFD and headed eastwards, observing a tornado to the SW of Kearney. We were behind it, and crossed the damage path, noting a house which had been severely damaged. The tornado was still causing damage and power flashes in Kearney.

We got ahead of the storm, but it began to weaken somewhat as it got near Grand Island. However, a new cell/mesocyclone quickly developed to the south of the initial storm, and quickly wound up into a beast. We remained ahead of it, and stopped just south of Aurora to observe it. The RFD rapidly approached us from the west - we saw what we thought might be a tornado at the north end of the RFD, and subsequently we've found out that it probably was, as a tornado caused damage just to the north of our location. The RFD also caused severe damage to the garage, with several UK and US chasers in it at the time - their vehicles were damaged too. Thankfully they escaped major injury.

We hurriedly left just before the RFD hit, and thankfully made the decision to head east (if we'd gone north, we'd have had a very close experience with the tornado).

The video below shows the storm approaching the petrol station.

We remained ahead of the storm, although had a pretty close call with the RFD as we headed north to the east of Aurora. We had to take a dirt road north, and this meant we couldn't travel at normal highway speeds. It was a pretty nerve-racking drive, but James kept us on the road, and we beat the RFD.

Matt took a great video of the RFD as we blasted north - see below.

Wednesday, 11 March 2009

That's 'ice'!

Weather and its effects never cease to amaze me, which must be a good thing seeing as I'm a meteorologist! This ensures that the job never becomes boring, as there is always some weather somewhere in the world to make you say, "wow".

Cue a winter storm in the Great Lakes region of the USA, and specifically in the state of Michigan. Strong winds pushed ice from Lake Huron into homes on the states eastern shoreline. Now, I'm sure we're all used to a bit of snow and ice, sometimes invading the doormat area of the home when a shoe is not firmly tapped to remove snow before entering the house. But these images from the CNN website are pretty amazing. It would be a rather rude awakening to stroll bleary-eyed into the kitchen in order to get the morning coffee warmed up, only to find yourself up to your neck in ice. Brrrrrr.

Tuesday, 10 March 2009

Why does it hurt so?!

The woman (Maya) to the right (well, I say woman - it's actually a computer program's depiction - the software in question is, "My Fitness Coach", on the Wii) has made standing up and sitting down a rather painfull excerise (pun almost intended) today. For last afternoon, I decided to start a fitness regime (long overdue), and turned to this piece of computerised muscle to start the process. In all fairness, it's a pretty good workout - I can tell this by the burning in my upper legs each time I stand up this morning! Even so, this is no bad thing, as it shows I must have been working quite hard - next session probably this evening, if my legs are up to it!

Saturday, 7 March 2009

The tallest ever man?

A discussion today has thrown up the incredible revelation that revered cricket commentator Jonathan Agnew is an incredible 1 mile tall*. This has raised a number of questions about how he goes about daily life, not least the (seemingly ordinary and mundane to us 'shorties') task of sitting down. Well, I can happily reveal the answer. Aggers (as he is known to loyal listeners of Test Match Special, which has nothing to do with ascertaining the best small incendiary device) has 250 hinged joints in his legs, which all collapse in beautiful symphony, allowing him to harmlessly, and effortlessly, glide down to seathood. Having done this, he can purr out the cricket news for hours on end. The small problem of standing up again is equally effortless, as numerous pneumatic devices extend the joints, and Aggers can rise proud into the evening air, the last rays of the setting sun setting him off a treat.

There, you've just learnt something new today.

* estimated height, based on a comparison to Ronnie Corbett.

Friday, 6 March 2009

McNuggets on charge!

I was rather amused to read about the American woman who called 911 because the McDonald's she was purchasing her meal from refused to give her a refund when the realised they didn't have any McNuggets! 'This is an emergency' she is said to have roared, when informed by the police that it was not as such, and that she shouldn't have called 911. This is, of course, true. I could have understood it if it were a double quarterpounder which had gone walkabout, but not the nuggets.

Wednesday, 4 March 2009

First post!

Well, here we go! It's been a long time coming but I have now decided to post my occasional rants and thoughts, as well as storm chase reports, into a blog. I don't know whether this will be just a phase, or whether I'll continue to update it, but let's be positive!