WINTER CONVECTION - 19th & 20th January 2003

BACK TO WEATHER-BLOG MENU

New! Fine Art Prints & digital images for sale-
Welsh Weather & Dyfi Valley landscapes Slide-Library - Click
HERE

Images from these two days of winter convection are posted below. Both days were identical in chasing terms - keep checking data then head out to the coast for the last three hours of daylight.



The satellite image for January 20 (courtesy Bernard Burton) shows deep convection to the SW of the UK and Eire with some outriders heading into Wales. The sferics (lightning strikes) plot for the 20th (below - courtesy Georg Mueller) echoes this pattern neatly..........



The Cardigan Bay coast is one of the better stormchasing areas of Mid-Wales, since you can usually see the "incoming" well in advance, out to sea....



Cbs over Cardigan Bay from Aberdyfi, Jan 19th ca. 3pm. It was much clearer to the N so that's where I was heading...



Long anvil-top streaming out from Cb over the Lleyn Peninsula. The whole system was drifting gently NE at this time.....



Close-up of northernmost Cb with some indistinct mammatus visible on this side.



Further south the line of Cbs is heading towards land. The weak gust-front is rippling the surface of the sea (dark area) and odd small lowerings and scud are also visible. The small funnel-shaped feature on the RHS of the image is probably scud: it did not last long.

Precipitation duly arrived and was moderate with odd small hail pellets. I waited for the shower to pass and the sun to re-emerge...



Another Cb is lagging behind the main line and is giving heavy precipitation to the south of my vantage point as the setting sun peeps through its northern flank...



The following day (January 20th) things looked a bit more promising. The Cbs had a more substantial appearance: these are the SW part of a clump out in the bay, photographed from Afon Dysinni, north of Tywyn. At the same time, behind and north of me, a small Cb had fired. It didn't appear to amount to much, but I hung around here and waited for it to pass, then went only half a mile to the north to catch the sun on its western side...



Striated small anvil with mammatus - not bad for what was a modest shower! Looking up the Dysinni towards Cadair Idris, with low-angle sunlight doing an excellent job of highlighting things. Obviously quite vigorous activity - although this was the last Cb to make landfall during daylight. Realising that this would be the case, I headed north to the coastal lookout points............



These are the same Cbs as in the last-but-one image. The southern one is decaying a little but a vigorous cell is building rapidly to its north, with a weakly overshooting top, which basically means the upward power of the convection is exceeding that of the high-level winds that stretch and flatten out the cloud-top into the characteristic anvil-shape. Although these were drifting in a NE heading, it would be dark before they made landfall, which would be to the north of here. As the light faded I headed back south to Tywyn.....




This is the last and best pic of the day! Taken from a lookout point on the Tywyn-Aberdyfi road. The view is looking NW. The new cells have now reached a mature stage, soaring skywards. New cells in the distance are part of another line of convection which gave heavy showers after nightfall. Lightning was recorded in SW Wales later that night.

All in all not a bad start to 2003! The best views would however have been from an aircraft flying around the SW Approaches, weaving in between what would without doubt have been some impressive storm systems.


BACK TO WEATHER-BLOG MENU

New! Fine Art Prints & digital images for sale-
Welsh Weather & Dyfi Valley landscapes Slide-Library - Click
HERE