This day looked promising from days before! A deepening upper-level trough with associated short-wave trough was
moving steady towards the Low Countries. The short-wave trough was expected to
increase in activity during the day, also resulting in a dynamic
impulse for the nearby cold front. Upstream of this front there was
strong advection of moist and warm air, with highs expected up to 27-
28 degrees over The Netherlands. Near the afternoon, when instability was likely to have build to 1000-
1500 J/Kg of MLCAPE.The combination of strong wind shear and high instability generated a
moderate probability of severe TSMS over the Benelux and WRN Germany,
with a chance of (short lived) supercells during the late afternoon
Already in the morning hours a MCS formed over eastern UK and the North Sea and this system affected coastal regions of Holland. As Ben Lankamp and I still had the idea that strong convection should develop over eastern Holland later in the day, we played the waiting game. But at 14 LT storms didn't form elsewhere and we were afraid the MCS inhibited convective development in other parts of the country. So we decided to head north, towards the province of Friesland. While driving in Flevoland we noticed storms building to our west. Near Lelystad we drove in its outflow and temperature dropped significantly. We found a vantage point, but the storm wasn't photogenic at al. On I-mode radar we saw that this storm was part o the inflow towards the MCS to our north. So we drove on and near Scherpenzeel we found the southern most of this system. It showed a nice flanking line with great crisp and rock solid towers. At the base of the storm a lowering was visible for a short period of time. Unfortunately this storm moved pretty fast, so we decided not to chase it anymore. We went to Lake Tjeukermeer to relax and decide what to do next.
After hanging around a bit we drove south again as a new MCS had moved into the province of Noord Holland. We thought we could have a great view of it on the otherside of Lake IJsselmeer, so we drove towards the Noordoostpolder. While driving us noticed new convection exploding to our east, but this was too far away and we continued south. Just west of Emmeloord we noticed an omnous looking low cloud band over the horizon. A shelf cloud! We drove to a farm road near Espel and shot many photos. The shelf progressed with great speed, so we had to drive east soon. Unfortunately the storm catched up with us, so there wasn't another opportunity for photography. We had to drive in rain and high winds for quite some time. Near Zwolle we encountered some small hail as well.
We decided to head towards East-Holland as new storms were developing in De Achterhoek. Unfortunately we got stuck in traffic near Deventer and missed all the action over Twenthe. That storm must have been one of the most severe of the day. After eating a meal at a Mc Donalds we headed towards Germany. There we drove in rain almost continuously, without seeing any photogenic. The storm north of Osnabrück was quite severe though, with very heavy rainfall. When the storms had cleared, we saw multiple bright white roll clouds over the western horizon, but due to lack of rest areas and many trees we couldn't make good photos of them! We succeeded when the roll clouds nearly dissipated.
All in all a pretty good chase, although the last 500 km of the chase were a bit unnecessary.