Synopsis
An active low pressure area (RACY), called Goretti, is located above the Night of Calais and moves east. This morning it reaches the southwest, continues east across the south of the country and leaves the country tonight. Goretti fills up over Germany on Saturday. The corresponding NW-ZO oriented occluding frontal system is located above the north and draws northeast. A weak occlusion (theta-w 925 hPa = 4°C) is present. The occluding front wraps all around the layer. At the back of this layer, with a northeast current very cold air enters our country. The turned-in occlusion is still above the southeast of our country on Saturday morning and leaves Saturday afternoon in activity declining the country. An elongator of a high pressure area over Scandinavia will spread over our country during Saturday. The NO-ZW oriented backpack is located on Saturday night above the northwest of the country and is slowly moving east.

Model assessment
The low clouds at the occlusion for the heat front and at the heat front in the south are fairly well picked up by the models, although the lowest bases are more south. In the north it has been snowing for a while and the transition from rain/wet snow to snow is now on the expected border. Especially on the Wadden, Groningen, Friesland and Drenthe this can lead to significant accumulation (5-10 cm, possibly local 10-15 cm, with EC giving the most precipitation). In combination with a rather powerful (over the northern coastal area hard) wind there is a real chance of snow hunting and the formation of snow dunes. In some places we see the snow thickness now also rapidly increasing. In the Har43-export we see at the occlusion in the north in a narrow band on the transition between rain/snow also a signal for freezing rain. Since this freezing rain would occur in an area with a snow deck, the possible impact will not be great and we do not put any emphasis on this. On the south flank of Goretti there is a lot of wind (heavy wind blows), but this seems to remain quite consistent in the model output (just) above Belgium. During the afternoon and evening we see more and more places where the rain passes into snow. However, the intensity is low. The far southeast (Limburg) is the closest to the low. There it could still snow for a long time, this is a focus.Attention

Wind
Around the layer Goretti is calculated a lot of wind. EC gives a little more wind than Har43. We start with coastal signals of 7 or possibly 8 Bft in the northern coastal area. At 8 Bft we speak of a snowstorm. Especially in the Limburg hills on Friday morning there is also a chance of wind blowing above 60 km/h, but the risk of code yellow (>75 km/h) is very low. In the north there remains above land for long 4-5 Bft. Only in the course of Saturday is the wind really decreasing.

View
See model assessment.

Temperature
Previously we saw temperatures of +7°C in Zeeland and thus the maximum seems to be reached. In the snow the temperature is around the freezing point. After passage of the layer, transport cold follows from the northeast. Saturday 10 January is recorded in many places, except the Zeeland coast, an ice day, with in the evening possibly already moderate to severe frost. Sensitivity temperature goes back to values below -10 degrees on Saturday night.

Cloud
At the fronts many ST/NS, see model assessment. In the south tonight and in the morning also TCUs with peaks up to 7000 ft.

Precipitation
See model assessment of precipitation at Goretti's closed front. In the afternoon the precipitation intensity of the snow in the north is a lot less. Later in the afternoon and evening the precipitation in the rest of the country, especially where it is still more active, goes over more places in (wet) snow, where there can also be a snow cover elsewhere. However, the intensity is much lower (1-3 cm per 6 hours). In Limburg there is a chance that this is higher (3-5 cm/6 h) and the snow can continue for a long time (also on Saturday), this is a focus.

Synopsis
Very cold air is being brought from the northeast. A high-pressure area over Scandinavia has an outskirts of our country moving east. Above the Atlantic Ocean lies a number of low pressure areas that are gradually approaching. Monday morning a frontal system passes. Above the Atlantic Ocean, a high trench sinks, causing softer air to flow over Western Europe. This trench weakens and passes Wednesday. Then it's a come and go of malfunctions.

Model assessment and uncertainties
Until Monday morning we are in very cold air, with possible feeling temperatures below -15 degrees. Sunday morning in the east it can be even -20 degrees or lower. The probability is now around 30% according to ECMWF. Already on Monday there will be a successful thaw attack. EC indicates that the most likely type of precipitation is snow, but at the same time indicates a significant risk of large-scale freezing rain (25-50%). This is a critical situation to monitor. After Monday there is almost no member with persistent winter weather.

Multi-day Summary
Sunday probably dry and very cold, with in the northeast chance of persistent fog. Feeling temperature drops to -15 degrees, in the northeast possibly to -20 degrees. Monday a thaw attack that will succeed. This creates snow from the morning onwards, which may turn into freezing rain. After Monday the cold disappears, we have average temperatures and rain falls from time to time.

EPS Period Summary
Variable and average temperatures.

Valid from Sunday 11 January to Friday 23 January