Some updates! A chase, an investigation and some hurricanes!

Firstly I must apologise for the lack of activity on this blog. Chances have been somewhat few and far between what with not having been on many chases this summer, and being busy with SkyWarn UK Overseas Territories - it's certainly quite active out there at the moment with recent storms including Hurricane Danielle, Hurricane Earl, Tropical Storm Fiona, Tropical Storm Gaston and perhaps Hermine on the way shortly!

And I this is what I shall start off with! The 2010 Atlantic hurricane season got off to what can be described as a slow start, at best. The past month or so, however, has seen La Nina set in with an associated increase in tropical cyclone activity. Hurricanes Danielle and Earl both reached category 4 on the Saffir-Simpson scale, both Cape Verde types. Danielle remained generally out to see but Earl has had more effects on land (including UK Territories - hence the busy period with SkyWarn UK) and continues to do so. Stay tuned to the National Hurricane Centre http://www.nhc.noaa.gov/ and SkyWarn UK OT http://www.skywarn.org.uk/OT for details on what's going on in the Atlantic!

The summer has yielded only one notable storm chase - and being perhaps the most active thunderstorm in the country it was something to behold! One possible funnel cloud was viewed on the cell - however given my distance at the time it could just as likely have been scud rising into the base. Day turned to night in the core with driving rain, while night turned to day in the frequent lightning with the storm! After chasing this particular cell for just over an hour, I called it a day when I found myself driving through flash flood conditions and darkness moving in quickly...

Perhaps the most interesting, yet humbling, thing I've done where the weather is concerned was a site investigation for a tornado in Suffolk. The damage was saddening to see but shows the sheer power of nature. What's more, the team and I rated this tornado at T3/F1 with wind speeds estimated between 93 and 114 mph - a weak tornado in the grand scheme of things. We submitted our findings to the European Severe Storms Laboritory who have fully verified the event (QC2) given our findings.

The full report can be found here:

http://www.skywarn.org.uk/Docs/Skywarn_Investigation_230810.pdf

Signing off for now, and I'll try not to leave it so long before the next one!

And as always, for our latest alerts on severe weather keep an eye on http://www.skywarn.org.uk/

Official warnings of severe weather can be found here: http://www.metoffice.gov.uk/

Sean

Night light extravaganza...

After more than a month of calm weather, summer was hinting at it's presence with afternoon temperatures soaring up to 30 degrees celcius on June 5th, 2010.

Unfortunately this would not be a day where I would be available to chase, but that was not going to be a problem, as it seems that the most active thunderstorm in the country would find me.

After a busy day at the aerodrome (fantastic weather - everybody was flying!), a few of us headed to Stamford, Lincs, for some dinner. Leaving the resaurant, the days instability let loose as we walked through a torrential shower in which the rain drops bounced off the street, leaving torrents of water flowing through the gutters.

The GFS model had forecast a very healthy 1000-1400 J/Kg of CAPE and LIs down to -5C by 18z, with an upper trough destabilising a very warm and moist airmass moving up from France. Driving home showed some development well to my south, which would eventually organise into a multicell cluster. It was this storm that I watched for hours, lighting up the night sky with peaks of around 20 strikes/minute. Plenty of CG lightning close to my position ensured that I would see the best night light show I've seen in well over a year.

Lack of overall shear meant that no real severe potential existed with these storms, but it was great to see nonetheless.

The following days brought a continued spell of unstable weather with thunderstorms and even possible funnel clouds reported, but any storms that I saw just wouldn't match up to the night light extravanganza on June 5th, 2010...

First chase day of 2010...

Sunday, 25th April 2010 brought the first storm chase day of 2010.

All things considered, the chance of documenting anything severe was near 0% due to the lack of overall shear, but having been 'proper' storm starved for months, the risk of widespread convection was too good to pass up. For days before, the GFS had been consistent in hinting at a chance of widespread deep convection with upper troughing behind a cold front, along with good spring diurnal heating leading to CAPE values in the region of 800 J/Kg, and LIs of -3 by late afternoon. Moisture would be marginal but sufficient for at least elevated convection.

I met with storm chase partner and designated driver for the chase, Jack, at about 1330BST. Before heading out to chase, we stopped at the local computer store in order to purchase the mobile broadband modem for this season.

Broadband in the bag, we headed toward our target area just to the southwest of the town of Wisbech, in the Fenlands of East Anglia. I chose this area in the hope instability would be maximised by giving the sun a chance to heat the land by the time the moisture arrived at our location. Also, with GFS forecasting some convergence in the region, we hoped (for a very small chance!) that a late afternoon sea-breeze would allow for the development of some misocyclones in the region and hence the small possibility of seeing a convergence zone funnel. For one reason or another, our mobile broadband failed to work, which would mean conducting this chase visually with no reference to radar/satellite and latest GFS data - makes life more difficult!

We stopped briefly to fuel up the car and ourselves, and by the time we reached our target area convection was beginning to initiate as expected. Parked on a narrow, quiet Fen lane, we could see for miles due to the flat nature of the Fens. After seeing some cumulus building quickly to our west-south-west, we decided that the most promising looking cell in the area would pass a few miles to our north, and so we went to reposition. Unfortunately, our road was closed due to a serious car accident - we stumbled across a scene of chaos with Police, Fire and Air Ambulance on scene - our thoughts go out to those involved in the accident, and wish all a speedy recovery.

The accident had delayed us somewhat, and with nothing visually vigorous to our southwest we decided to call it a day. We could see maturing cells both to our north and south, but time restraints meant we could not travel so far to intercept these cells. We did however get close enough to some of the cells to appreciate the structure.

With this chase being based on a marginal set-up, all things considered it was a semi-success. We did get to see some storm structure, and though not documenting anything of note, it was a good practice run for the set-ups we hope to see throughout this year! The broadband will be working for the next one!

Some pictures from this chase can be seen here: http://picasaweb.google.com/107852667503069707766/April25th2010StormChase#

No real hints at any chasable days for the forseeable future, so, until next time!

Sean

Welcome to my chase blog...

Welcome to my storm chase blog.

I have set-up this blog to document and share the experiences that I come across while chasing and observing mother nature at her most powerful.

I hope you enjoy my future blogs - thanks for visiting.

Sean