La Nina and it's effect on Summer T Storms

[The PIT]

So are there any links in Thunderstorm activity and La Nina???

We got all the rain before La Nina started last year despite experts who should know better saying otherwise.

[Lettucing Gutted]

I think it depends on the synoptics that La Nina predisposes us to. In La Ninas that brings warm tropical synoptics in summer (eg summers of '75 and '89) thunderstorms are common in Spanish plume and tropical air moving over warm ground scenarios.

However in La Ninas that brings cool polar synoptics in summer (eg summers of '85 and '88) thunderstorms are common in unstable maritime polar air moving from Greenland and the North Pole over the warm North Atlantic Ocean as well as cool maritime polar air moving over warm land. In cool summers thunderstorms also occur along frontal boundaries between polar and tropical air.

[kold weather]

I think to be honest it doesn't matter so much in summer because usually by that time it weakens alot anyway generally though are expcetions, though I don't think this summer is going to be one of them even if la nina will no doubt still be present.

I'll look into it though because I dare say that because la ninas tend to favors +ve NAO and Scandinavian highs if the jet is quite far to the north however if the subtropical bet sets up quite far south then it all flattens out somewhat and you end up with a westerly dominated summer, thats probably what happened last summer though whether la nina caused that 'm not so sure as it was still only just starting to develop at that point and actually we had a very powerful -ve NAO for much of last summer which goes completly against what you tend to see in la nina patterns, esp when they do get beyond a certain point.

[damianslaw]

I just want this la nina to relent and I'd be quite happy if we don't see a strong la nina for a long time.

Don't like strong la nina it has wrecked our winter.

[Snowyowl9]

Just been looking back at the last la nina summers and those were very thundery summers better than last summer by quite a long way with many more thunder days here and it more or less came in with a bang from this with thundery showers and a loud crack of thunder under the centre of the low I can remember that day too. :wacko:

http://www.wetterzentrale.de/archive/ra/19...00119990602.gif

The previous year 1998 was a very poor summer for thunder here though.

[The PIT]

Well last summer here was poor for storms we just missed them. Bad for extreme rain though. However there wasn't a La Nina present just neutral conditions if I remember properly. So if La Nina means loads of storms I'm all for it.

[Gray-Wolf]

I'm worried that , like last year , there will be a lot of cold water flowing into the northern atlantic (around Greenland) on the arctic drift as the single year ice flushes out into the mid atlantic leading to enhanced precipitation on the atlantic coastlines.

Couple a wet depression with an African plume (with the clean stratosphere adding a little more V'V'Voom to things by the extra energy it allows in at ground level) and we will have the basics for fireworks similar to the mid west USA......

[Gavin P]

The issue about last summer, in my view, was the rapid tansition from El Nino to La Nina like conditions. That sudden switch was the fuel to give us such a horrible summer.

This summer is set to be quite differant. It may be a poor summer if La Nina remains strong, but if it weakens through spring, I could see us having a reasonable summer.

[Weather-history]

I think it depends on the synoptics that La Nina predisposes us to. In La Ninas that brings warm tropical synoptics in summer (eg summers of '75 and '89) thunderstorms are common in Spanish plume and tropical air moving over warm ground scenarios.

Its interesting you mention summer 1989 because that was the most thunderless summer for Manchester on record. There wasn't a single day of thunder recorded in any of the summer months of 1989.

Summer 1989 wasn't exactly remembered for its thunder overall.

[Nick F]

Its interesting you mention summer 1989 because that was the most thunderless summer for Manchester on record. There wasn't a single day of thunder recorded in any of the summer months of 1989.

Summer 1989 wasn't exactly remembered for its thunder overall.

One of the best overnight storms I've witnessed in the UK occured in mid-June 1989 in Kent, one of those Spanish Plume MCS storms that last for several hours in the early hours with frequent lightning and loud thunder - a rare beast in recent years.

Btw, have moved this thread into Storms and Extreme Weather ...

[PersianPaladin]

The problem with spanish-plume systems is that of late; they either venture up the maritime regions of western Britain - sustained through differential advection...or they just come in from France, decay a bit over the channel and hang around in south-east England or East Anglia before fading away.

I'd actually like to see this sort of MCS affect my region once more.

[Snowyowl9]

Actually last year was very good just looked and there was 8 or 9 days with thunder heard with this being the best spanish plume for a few years giving some spectacular thunderstorms during the evening,thunder also in the afternoon for an hour.

http://www.wetterzentrale.de/archive/ra/20...00120070619.gif

Nothing in May.

1998 only gave 1 summer day June 1st with just a few rumbles of thunder wow,May was better that year though with 4.

1999 gave 13 days.

2000 with 11 and all that including May.

[PersianPaladin]

We could end up with a weak El Nino this summer...if NOAA's forecast is accurate: -

http://www.cpc.noaa.gov/products/predictio...efing/sstaa.gif