![\"Fig.](\"http:\/\/www.essl.org\/\/testbed\/blog\/wp-content\/uploads\/2013\/07\/2013070812_06610_skewt.gif\")
<\/a>Fig. 1a.<\/p><\/div>\n
<\/a>Fig. 1b.<\/p><\/div>\n
However, the Serbian wind events were impressive enough, given that the Belgrade proximity sounding looked equally inconspicuous (Fig. 1b). Additionally, reports of marginally severe hail events arrived from Serbia, the Swiss and French Alps and the Italian West coast, and reports of excessive rainfall from Serbia, Bosnia-Hercegovina and Croatia (Fig. 2).<\/p>\n
<\/a>Fig. 2: ESWD reports (yellow: severe wind, green: large hail, blue: excessive rain) between 06 UTC Mon 8 July and 06 UTC Tue 9 July 2013.<\/p><\/div>\n
Altogether, the number of severe weather events was higher than we expected on such a seemingly quiescent day. It was a gentle reminder that even though heavy rain is the dominant and obvious risk with storms on such days, at least localized events of marginally large hail and severe downbursts should not be left unconsidered. Maybe a level 1 is appropriate for regions with a more robust instability release even in the absence of noteworthy vertical wind shear.<\/p>\n
<\/a>Fig. 4: Verification of the nowcast issued at 14 UTC Mon 8 July 2013, valid for the 14 to 16 UTC period.<\/p><\/div>\n
It is needles to say that forecasting, and even more nowcasting, of such storms is particularly difficult. Fig.\u00a03 shows yesterday’s 14 UTC nowcast (valid for 14 to 16 UTC) for the Munich domain, which did not verify positively at all.\u00a0Three different areas were covered with rain watches, where either young and healthy-looking storms were already present or new daughter cells seemed about to initiate. The storm over the Italian Alps was the only one\u00a0for which\u00a0an additional hail threat was mentioned, since it seemed to be close enough to ingest the best low-level moisture over the Po Valley, allowing the strongest instability release. However, within the following two hours hail was reported from the French and Swiss Alps instead, while the “shadowed” storms started to decay rather soon. Fig. 4 tries to illustrate how difficult it is to do nowcasting for such a mosaic of “popcorn storms”: which of the dozens of unorganized storms will be the next\u00a0big thing?<\/p>\n
<\/a>Fig. 4: Nowcast display at 1530 UTC 8 July 2013: Meteosat E-view satellite image and EuRadCom radar composite.<\/p><\/div>\n
A more thorough weather discussion will follow in a separate post by\u00a0this week’s\u00a0newly acquired guest writer. \ud83d\ude09<\/p>\n","protected":false},"excerpt":{"rendered":"
By the time of writing, 21 severe weather reports have arrived for yesterday’s\u00a0(Mon 8 July 2013) pulse storm activity over the mountain areas across the Southern half of Europe.\u00a0Our Bosnian Testbed participant Milica deserves special credits for retrieving and entering … Continue reading