Storm Forecast
Valid: Tue 30 Jun 2015 06:00 to Wed 01 Jul 2015 06:00 UTC
Issued: Mon 29 Jun 2015 14:40
Forecaster: DAHL / PUCIK

A level 1 was issued for Northern Iberia and the Pyrennees mainly for large hail and severe wind gusts.

SYNOPSIS

An upper ridge is amplifying over Central and Western Europe, flanked by two troughs at its eastern and western periphery. An exceptionally hot airmass at the base of an elevated mixed layer will be advected from Iberia across Western France into the Southern UK. Over Eastern Europe, rather cool mid-tropospheric temperatures will contribute to weak to moderate CAPE and an abundance of diurnally-driven thunderstorms.

DISCUSSION

... Northern Iberia / Pyrennees and surrounding area ...

Isolated, diurnally driven thunderstorms are possible especially over the mountainous areas of Northern Iberia. Steep lapse rates, a deep and dry boundary layer, as well as moderate to strong deep layer shear (15 - 25 m/s, increasing towards west) may promote large hail and severe wind gusts.

... Greece towards western Ukraine ...

Scattered to widespread DMC is forecast within a regime of weak vertical wind shear. Most likely convective mode will be poorly organised multicells. Due to the very slow storm motion and high storm coverage, a heavy rainfall event or two are not excluded. Also, hail approaching severe levels (or large quantities of small hail) are possible with stronger updrafts. Overall, the risk seems to be too small to warrant a Level 1.