When a weather system comes over, it normally follows a standard pattern. Wind is from a certain direction which then shifts the moment the front passes. Normally that front looks a bit like an R. As you can see from the cut out of the weather chart from yesterday, that weather front laid over Nova Scotia but its tail came halfway down the North Atlantic. Red indicates a warm front and blue a cold front and they form the boundary between two separate regions of weather. The difference between cold and warm does not need to be that great. 10oF or so if often enough, especially in regions where there is the influence from the Gulf Stream.
When we left the shelter of the Bahamas a cold front had just passed by and then the wind changes as the High pressure – low pressure locations are different on each side of the front itself. Thus for us the wind shifted to the South West while we sailed north east towards Bermuda. And because we had a high pressure system in the back and a low pressure system ahead of us the wind blew the clouds away and smoothed the waves and thus we had beautiful day at sea and later in Bermuda. There the wind started to increase, indicating a new front coming over, which did so during the night. Now we are in that frontal system, right between the two legs and so we get a lot of rain as the warmer air condensates all the moisture once it gets hit by colder air. If this weather front keeps doing what it is doing at the moment, it will start to pass by late afternoon and then we will have a nice sunny day tomorrow. Because the winds keep opposing each other with each frontal system, the wind does not get the chance very much to push up the waves and thus we are having a steady ride.
We are not the only ship here, the Regal Princess has followed us from Bermuda as she is also going to Ponta Delgada in the Azores. At the moment she is scheduled to arrive 45 minutes behind us but the captain could always change his mind. The strange thing for everybody on board is that although the ship is supposed to arrive after us, she is overtaking us. This has to do with different engine configurations. The ss Rotterdam has five Sulzer 16 cylinder engines which can produce 25 knots if needed. For 16 knots we only need two engines and for 19 knots only three engines. As power versus speed is not linear we need a fourth and fifth engine just to deliver those last 6 knots going from 19 to 25 knots. While one engine could take us from 0 to 6 knots in the low speed range. At the moment we are making surplus speed, because we have current and wind behind us. We started out on 4 engines and we will stop an engine as soon as the remaining engines can maintain the average speed needed.
The Regal Princess has four engines (2 x 12 cylinder Wärtsilä 12V46F and two 14 cylinder Wärtsilä 14V46F) This means that when they will stop an engine it will be at a different average speed to maintain. Their four engines deliver a maximum speed of 22 knots, and will reach the “3rd engine stage” at a different time. Then we will overtake her again to be first at the pilot station, unless they change their ETA. (Estimated Time of Arrival)
We will also meet the Zenith of Pullmantur in Ponta Delgada and then the Regal Princess so will sail together with the Zenith to Lisbon while we head north towards Brest in France.
For us at the moment the question is, will the band of rain that came by this afternoon rain out, or ep a higher speed than the ship, or go slower than the ship and will we will have a nice sunny day. The weather forecast says yes; so we also hope for yes.
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