* Southern Europe hit by heatwave, crops suffer
* Analysts cut crop estimates, notably top producer France
* European wheat futures surge to near 1-year highs
* Germany, Poland, UK heading for higher crops after rain
PARIS, June 20 (Reuters) - A heatwave hitting France and southern Europe will damage this year's wheat crops, mainly in top EU producer France and in Spain, while rainfall benefited crops in Germany, Poland and Britain where they are expected to be higher, analysts said.
Mounting concerns about the impact on crops of a heatwave in France, the European Union's biggest wheat grower and exporter, sent Euronext wheat futures rocketing to near one-year highs on Tuesday.
"It's clear that the very hot temperatures are degrading crop potential in Europe but it is too early to say by how much," the head of French consultancy Agritel Michel Portier said.
Analysts have lowered grain crop estimates in recent weeks, with Strategie Grains cutting its EU soft wheat crop estimate by 1.1 million tonnes last week to 141.6 million.
Agritel lowered its French soft wheat crop forecast to 36-37 million tonnes from 37.1 million seen last week, because of scalding damage, Portier said, adding that the forecast would need to be fine-tuned, depending partly on next week's weather.
Forecaster Meteo France currently sees temperatures falling back to average levels from the end of this week.
France last year harvested its lowest crop in decades at 28 million tonnes after poor spring weather, tumbling from a record 41 million in 2015.
In Spain, this year's extreme weather – from the frosts over the winter to recent record high temperatures – will mean a soft wheat crop of 3.7 million tonnes, down from 7.2 million last year, farmers association Cooperativas Agro-alimentarias said.
In the EU's second largest producer Germany, wheat is developing well after a rainy June helped crop development after an unusually dry start to the spring.
"Overall the picture is satisfactory and Germany is on course for a good, average crop this summer as we have not had the weather extremes seen in other parts of Europe," one German grains analyst said.
"The next 2-3 weeks will be critical for yields and a mix of sunshine and rain is needed."
Germany's 2017 wheat crop will increase 3 percent on the year to 25.20 million tonnes, the country's cooperatives association estimated on June 14. This was up from 24.98 million tonnes the association had estimated in May.
In the fourth largest producer Poland, crops also benefited from recent rain, said Wojtek Sabaranski of analysts Sparks Polska, which estimates the country will harvest 11.3 million tonnes in 2017, up 1 percent on the year.
Britain's wheat crop appears in good condition with scope for a modest increase in production this year.
Trade estimates for this year's UK wheat crop range from around 14.5 million to 15.0 million tonnes, up slightly from last season's 14.38 million.
"Over the last two or three weeks, estimates have gradually begun to creep upwards," analyst Jack Watts of the Agriculture and Horticulture Development Board <AHDB) said. (Reporting by Sybille de La Hamaide, additional reporting by Clement Rouget in Paris, Paul Day in Madrid, Micheale Hogan in Hamburg and Nigel Hunt in London, editing by David Evans)