:00:00. > :00:08.Hi guys, Ayshah here, with the weekend stories you need to know.
:00:09. > :00:12.Coming up: It's been called BMXing on snow - we'll tell you how Great
:00:13. > :00:14.Britain got on in the awesome Snowboard Cross.
:00:15. > :00:18.And from snowboards to surfboards - we'll bring you the curly tale of
:00:19. > :00:25.the pig who rides the waves. This is Newsround.
:00:26. > :00:27.So, first - all this week we've been telling you about some truly
:00:28. > :00:30.extraordinary weather conditions that have been causing terrible
:00:31. > :00:37.problems, not just here, but in America, too. So, what's causing all
:00:38. > :00:41.this weird weather? As I've been finding out, it's all to do with a
:00:42. > :00:54.global wind, high above us: the jet stream.
:00:55. > :00:59.In the wind and rain. In the US, they're in the grip of a cold winter
:01:00. > :01:03.that shows no of stopping. Scientists don't think this is just
:01:04. > :01:10.a coincidence. They believe the recent warming of the Arctic is
:01:11. > :01:18.driving weather conditions here. That is this current, here, in red.
:01:19. > :01:22.It's called the Jetstream. It has caused months of heavy rain and
:01:23. > :01:28.storms for us, and extreme cold for America. This scientist has been
:01:29. > :01:33.studying the Jetstream, and things we could see more of the same in the
:01:34. > :01:39.future. I think we should expect is to occur
:01:40. > :01:43.more frequently. It's being these wavy patterns in the Jetstream and
:01:44. > :01:49.that tends to result in weather conditions being very persistent in
:01:50. > :01:51.one place. Early to judge whether the
:01:52. > :01:57.Jetstream's change in shape is permanent. As we may have to get
:01:58. > :02:00.used to whether that stays the same for weeks or even months.
:02:01. > :02:03.In this country, we've seen severe flooding affecting thousands of
:02:04. > :02:05.people throughout the south of England, while hurricane-force
:02:06. > :02:09.storms have battered the coastlines of much of Britain in recent days.
:02:10. > :02:12.Meanwhile, over in America, they're suffering a prolonged, bitterly cold
:02:13. > :02:16.winter which is showing no sign of calming down. Back here in Britain,
:02:17. > :02:18.the Prime Minister has warned that flooding misery is likely to
:02:19. > :02:22.continue for millions of people, despite a break in the bad weather.
:02:23. > :02:25.David Cameron said that many places in southern England, where the
:02:26. > :02:28.ground is already soaked, may see further flooding. One of the biggest
:02:29. > :02:31.threats is not from rivers bursting their banks, but from water
:02:32. > :02:33.underground, coming to the surface. Check this out.
:02:34. > :02:35.One of the reasons we are seeing so much flooding is ground water
:02:36. > :02:38.flooding. This happens when water rises from rocks under the ground,
:02:39. > :02:45.and comes out on the ground service. -- surface. When enough
:02:46. > :02:53.rain in these areas, what keeps moving down beyond the surface. It
:02:54. > :03:00.tends to move from higher ground to lower ground. When we have a lot of
:03:01. > :03:04.rain, water starts to come out of the ground surface in places that
:03:05. > :03:10.are usually drive. We call this ground water flooding. It takes
:03:11. > :03:16.longer to go away and flooding from rivers. It can last for weeks or
:03:17. > :03:20.even months. Next, we're off to Russia and the
:03:21. > :03:23.Sochi Winter Games. Today, we've been enjoying a thrill-packed sport
:03:24. > :03:26.that's been likened to BMXing on snow - it's the snowboard cross. Six
:03:27. > :03:29.riders carve down the course, braving huge jumps and sharp
:03:30. > :03:35.corners, and with everyone so close together you can have some nasty
:03:36. > :03:38.crashes. Team GB's Zoe Gillings did make the semi-finals this morning
:03:39. > :03:41.and came within just a few centimetres of making the final -
:03:42. > :03:49.but unfortunately she just missed out. She did finish in the top ten
:03:50. > :03:52.overall, though. Well, you've been telling us about
:03:53. > :03:57.your Sochi highlights over on the Newsround website. Ashleigh from
:03:58. > :04:00.Boston in Lincolnshire says, my highlight has been the speed
:04:01. > :04:08.skating, it's amazing how fast they go without falling over! Farsya in
:04:09. > :04:10.Birmingham said, I never knew what curling was before, but now I want
:04:11. > :04:26.to try it Thanks so much for all those
:04:27. > :04:28.comments, keep them coming in. Speaking of the curling then,
:04:29. > :04:32.Britain's men's curling team were beaten 7-6 in their second to last
:04:33. > :04:35.round robin match with Norway this morning, so they're not guaranteed a
:04:36. > :04:39.semifinal place yet. The match went down to the final end of the game
:04:40. > :04:43.with the scores level at 6-all, but the Norwegians won with the final
:04:44. > :04:46.stone. Team GB can still make the semis if they beat China tomorrow
:04:47. > :04:51.afternoon. Britain's women play their last two matches tomorrow as
:04:52. > :04:54.well. In today's matches, Arsenal will be
:04:55. > :04:58.hoping to avoid another scoreline like this when they face Liverpool
:04:59. > :05:01.again in the big four o'clock showdown. In the afternoon's other
:05:02. > :05:03.games Everton face Swansea in the early kick off at 1.30PM and
:05:04. > :05:12.Sheffield United play Nottingham Forest at 3PM.
:05:13. > :05:16.Next up, what are all these people up to behind me? Well it's a world
:05:17. > :05:19.record attempt of course! Thousands of young Pakistanis braved heavy
:05:20. > :05:25.rainfall in the city of Lahore yesterday trying to break the world
:05:26. > :05:28.record for the largest human flag. More than 29,000 students made a
:05:29. > :05:33.giant version of their national flag out of pieces of card - and they
:05:34. > :05:37.think they've set a new record! Top work, guys!
:05:38. > :05:40.Last up, a curly tale of a surfing pig. No, I'm not telling porkies.
:05:41. > :05:44.This water-loving piglet called Kama loves to go swimming with his owner
:05:45. > :05:49.in America. Is Here he is catching the waves at Hawaii's Sandy beach.
:05:50. > :05:53.The pigs love of surfing started when he used to swim with his owner
:05:54. > :05:58.in a pool in the back garden, and look at him now.
:05:59. > :06:02.I'll be back with your last bulletin of the day before 2PM.