Crying, yelling - or simply asking for summer in them middle of May, is a bit bit premature, given that the normal MAX temperatures in Stockholm this time of the year are around 17°C. However, I consider 20°C and more, already a more "summer like" - at least for us Scandinavians.

For the time being, we have rather unstable and chilly weather. With rain - which is very good for nature - but dampening daytime temperature, being quite a bit below average.

GFS vs ECMWF

are not in agreement when it comes to the upcoming weather development in Stockholm, and Middle/North Europe in general.

GFS calls for unstable weather, with low pressure areas and brief high pressure ridges. While the European weather service, calls for the creation of a high pressure area over middle Europe, which would lead into summer temperatures. Albeit now, with a twist; that the high pressure ridge may not stay stable over Scandinavia (only over middle Europe). Plus that they also think, that towards the end of May, that a strong inflow of cold air could happen over Scandinavia.

Oh well...

It seems like the various weather centers; their calculation for 10-14 days, seem to divert pretty much. Overall they indicate now more unstable weather.

Summer still seem to wait a while.

GFS Prognosis
(Stockholm)

ECMWF Prognosis
(Stockholm)