Below are the optimal routing results in Table form. The inputs to this routing would include GFS wind, Wave, pressure, and rain information as well as RTOFS Ocean Current (direction, speed, sea temp). Expedition combines that with performance data for the boat in the form of a polar diagram as well as some factors that reduce the predicted speed of the boat based on significant wave height to try to seek lower wave heights.
The output shows as series of waypoints (route) that it suggest the boat go along with the predicted time the boat will be at that location, the forecast True Wind Direction (TWD) and True Wind Speed (TWS) along with the True Wind Angle (TWA - that is the angle between the bow and the True Wind). It calculates the expected Boat Speed (Bsp) that the boat will go in those conditions and the headsail that it presumes you would be using to make that speed. J1 is the Jib, Code0 is the Reacher, and Engine is output when it predicts that you would be best served to run the engine in those conditions to keep speed up, either because the wind is too light, or too close to the bow to make good progress at sail alone. It then gives your Heading to the next waypoint (Brg) and the Distance to the next calculation point. Shorter routes get waypoints closer together and longer routes space the waypoints out to simplify the calculation a bit. It also lists the forecast atmospheric pressure (MSLP) Rain, and Significant Wave Height, and finally the Lat/Lon of the calculation waypoint.
| Atlantic Daylight Time | Twd°M | Tws | Twa | Bsp | Sail | Brg°M | Dist nm | MSLP | Rain | SigWave H | Latitude | Longitude |
| 5/28/2016 9:30 | 124° | 8 | 85° | 5.8 | J1 | 039° | 36.29 | 1025.2 | 0 | 0.9 | 32 22.854n | 064 38.112w |
| 5/28/2016 15:28 | 134° | 6.3 | 88° | 6.3 | Code0 | 046° | 36.31 | 1026 | 0 | 0.9 | 32 55.940n | 064 20.411w |
| 5/28/2016 21:07 | 146° | 5.3 | 100° | 6.5 | Code0 | 046° | 36.27 | 1025.7 | 0 | 0.8 | 33 27.016n | 063 57.972w |
| 5/29/2016 2:43 | 163° | 2.4 | 117° | 6.4 | Engine | 046° | 36.31 | 1025.6 | 0 | 0.8 | 33 58.138n | 063 35.587w |
| 5/29/2016 8:23 | 279° | 3 | -133° | 6.4 | Engine | 052° | 36.42 | 1025.8 | 0 | 0.7 | 34 29.230n | 063 12.905w |
| 5/29/2016 14:09 | 303° | 6.6 | -105° | 6.1 | Code0 | 048° | 36.39 | 1025 | 0 | 0.7 | 34 58.255n | 062 46.146w |
| 5/29/2016 20:13 | 320° | 7.8 | -90° | 5.9 | J1 | 050° | 36.47 | 1024 | 0 | 0.9 | 35 28.952n | 062 22.232w |
| 5/30/2016 2:32 | 331° | 8 | -84° | 5.8 | J1 | 055° | 36.57 | 1022.7 | 0.02 | 1 | 35 59.161n | 061 57.070w |
| 5/30/2016 8:32 | 090° | 4.7 | 35° | 6.4 | Engine | 055° | 36.67 | 1022.9 | 0.05 | 1.1 | 36 27.668n | 061 28.672w |
| 5/30/2016 13:55 | 160° | 9.8 | 95° | 7.2 | Code0 | 065° | 37.28 | 1022.5 | 0.01 | 1.1 | 36 56.314n | 061 00.120w |
| 5/30/2016 19:16 | 177° | 9.9 | 101° | 7.4 | Code0 | 077° | 38.77 | 1022.4 | 0 | 1.2 | 37 20.704n | 060 24.749w |
| 5/31/2016 0:29 | 195° | 11.9 | 107° | 8.3 | Code0 | 087° | 40.69 | 1021.6 | 0 | 1.4 | 37 39.653n | 059 42.114w |
| 5/31/2016 5:21 | 208° | 14.4 | 111° | 8.9 | Code0 | 096° | 42.71 | 1021.1 | 0 | 1.5 | 37 52.690n | 058 53.351w |
| 5/31/2016 10:12 | 220° | 15.8 | 121° | 8.9 | Code0 | 098° | 44.21 | 1021.1 | 0 | 1.6 | 38 00.000n | 058 00.000w |
| 5/31/2016 15:27 | 231° | 17.6 | 149° | 7.7 | Code0 | 082° | 45.15 | 1020.5 | 0 | 1.9 | 38 06.013n | 057 04.384w |
| 5/31/2016 21:26 | 246° | 18 | 160° | 7.5 | Code0 | 086° | 44.35 | 1020.1 | 0.03 | 2 | 38 24.658n | 056 12.022w |
| 6/1/2016 3:32 | 257° | 20.9 | -156° | 7.4 | Code0 | 053° | 51.69 | 1017.8 | 0.03 | 2.2 | 38 40.240n | 055 18.939w |
| 6/1/2016 10:34 | 270° | 22.2 | -145° | 7.3 | Code0 | 055° | 48.76 | 1016.6 | 0.3 | 2.7 | 39 21.654n | 054 39.128w |
| 6/1/2016 16:18 | 297° | 19.7 | -148° | 8 | Code0 | 086° | 48.45 | 1014.8 | 2.02 | 2.9 | 40 00.000n | 054 00.000w |
| 6/1/2016 22:00 | 325° | 16 | -125° | 8.4 | Code0 | 091° | 47.99 | 1015.5 | 0.5 | 2.5 | 40 17.039n | 053 00.669w |
| 6/2/2016 3:25 | 352° | 16.1 | -121° | 9 | Code0 | 114° | 43.31 | 1017.3 | 0.18 | 2.4 | 40 30.000n | 052 00.000w |
| 6/2/2016 8:04 | 011° | 20 | -117° | 9.8 | Code0 | 129° | 52.99 | 1018.4 | 0.1 | 2.3 | 40 24.456n | 051 03.557w |
| 6/2/2016 13:29 | 012° | 20 | -111° | 9.8 | J1 | 123° | 47.75 | 1019 | 0.09 | 2.3 | 40 03.848n | 049 59.605w |
| 6/2/2016 18:24 | 005° | 18.5 | -113° | 9.7 | Code0 | 119° | 47.38 | 1019.9 | 0.07 | 2.4 | 39 50.000n | 049 00.000w |
| 6/2/2016 23:23 | 356° | 18.7 | -117° | 9.7 | Code0 | 114° | 47.09 | 1019.5 | 0.06 | 2.5 | 39 39.274n | 047 59.979w |
| 6/3/2016 4:35 | 343° | 19.3 | -126° | 9 | Code0 | 109° | 46.9 | 1017.9 | 0.07 | 2.7 | 39 32.602n | 046 59.484w |
| 6/3/2016 10:05 | 326° | 19.2 | -158° | 7.7 | Code0 | 125° | 49.18 | 1016.2 | 0.09 | 2.8 | 39 29.845n | 045 58.795w |
| 6/3/2016 16:43 | 311° | 20.5 | -162° | 7.4 | Code0 | 113° | 47.52 | 1013.8 | 0.09 | 3.2 | 39 13.163n | 044 58.955w |
| 6/3/2016 23:31 | 303° | 22 | -100° | 9.1 | J1 | 043° | 84.97 | 1011.6 | 0.11 | 3.5 | 39 06.568n | 043 58.265w |
| 6/4/2016 9:16 | 323° | 21.3 | -114° | 9.5 | J1 | 076° | 46.65 | 1006.8 | 0.23 | 40 21.263n | 043 05.588w | |
| 6/4/2016 14:08 | 325° | 18.6 | -110° | 9.7 | Code0 | 075° | 46.07 | 1006.8 | 0.2 | 40 43.168n | 042 11.398w | |
| 6/4/2016 18:55 | 325° | 17.8 | -110° | 9.6 | Code0 | 076° | 45.46 | 1006.6 | 0.2 | 41 05.474n | 041 18.063w | |
| 6/4/2016 23:43 | 321° | 16.4 | -111° | 9.4 | Code0 | 073° | 45.45 | 1006.6 | 0.16 | 41 26.999n | 040 24.788w | |
| 6/5/2016 4:37 | 325° | 14.7 | -111° | 9.1 | Code0 | 075° | 44.82 | 1006.3 | 0.19 | 41 50.477n | 039 32.703w | |
| 6/5/2016 9:28 | 331° | 16.1 | -102° | 9.3 | Code0 | 073° | 44.81 | 1005.9 | 0.26 | 42 11.714n | 038 39.584w | |
| 6/5/2016 14:18 | 319° | 15.7 | -107° | 9.4 | Code0 | 065° | 45.53 | 1006.5 | 0.14 | 42 34.111n | 037 47.047w | |
| 6/5/2016 19:17 | 308° | 15.3 | -115° | 9.1 | Code0 | 063° | 45.44 | 1007.1 | 0.04 | 43 01.879n | 036 57.864w | |
| 6/6/2016 0:16 | 303° | 16.5 | -118° | 9.3 | Code0 | 061° | 45.32 | 1006.8 | 0.03 | 43 30.847n | 036 09.771w | |
| 6/6/2016 5:18 | 294° | 18.9 | -119° | 9.6 | Code0 | 053° | 46.72 | 1005.7 | 0.03 | 44 00.830n | 035 22.709w | |
| 6/6/2016 10:20 | 286° | 19.9 | -153° | 7.9 | Code0 | 079° | 43.66 | 1004.3 | 0.11 | 44 36.351n | 034 40.299w | |
| 6/6/2016 15:58 | 278° | 19.3 | -161° | 7.6 | Code0 | 079° | 43.67 | 1003.4 | 0.13 | 44 53.440n | 033 43.728w | |
| 6/6/2016 21:45 | 270° | 19.2 | -162° | 7.6 | Code0 | 071° | 43.41 | 1002.7 | 0.21 | 45 10.400n | 032 46.779w | |
| 6/7/2016 3:27 | 271° | 18.6 | -160° | 7.6 | Code0 | 071° | 43.36 | 1001.9 | 0.27 | 45 32.351n | 031 53.479w | |
| 6/7/2016 9:11 | 266° | 18.7 | -173° | 7.3 | Code0 | 079° | 43.57 | 1000.5 | 45 54.379n | 030 59.976w | ||
| 6/7/2016 15:11 | 260° | 17.9 | -179° | 7.2 | Code0 | 079° | 43.58 | 1001.3 | 46 11.098n | 030 02.007w | ||
| 6/7/2016 21:13 | 251° | 18 | -171° | 7.3 | Code0 | 062° | 43.67 | 1001.6 | 46 27.627n | 029 03.611w | ||
| 6/8/2016 2:58 | 276° | 18.7 | -131° | 8.4 | Code0 | 047° | 46.77 | 1003.2 | 46 54.762n | 028 13.732w | ||
| 6/8/2016 8:10 | 287° | 20.2 | -127° | 8.8 | Code0 | 054° | 44.06 | 1003 | 47 32.557n | 027 33.152w | ||
| 6/8/2016 13:08 | 289° | 17.4 | -124° | 8.9 | Code0 | 053° | 43.53 | 1003.8 | 48 04.683n | 026 48.254w | ||
| 6/8/2016 17:59 | 298° | 15.1 | -118° | 8.8 | Code0 | 056° | 42.01 | 1005.4 | 48 36.406n | 026 03.408w | ||
| 6/8/2016 22:39 | 306° | 15.1 | -116° | 8.9 | Code0 | 062° | 41.75 | 1006.5 | 49 05.395n | 025 17.208w | ||
| 6/9/2016 3:23 | 306° | 14.7 | -114° | 8.9 | Code0 | 060° | 41.74 | 1007.2 | 49 30.844n | 024 26.442w | ||
| 6/9/2016 8:02 | 304° | 15.3 | -111° | 9.2 | Code0 | 055° | 41.4 | 1008.1 | 49 57.705n | 023 37.001w | ||
| 6/9/2016 12:32 | 300° | 15.6 | -115° | 9.1 | Code0 | 056° | 40.74 | 1007.2 | 50 26.724n | 022 50.878w | ||
| 6/9/2016 17:11 | 290° | 15.9 | -144° | 7.5 | Code0 | 074° | 40.6 | 1006 | 50 54.733n | 022 04.200w | ||
| 6/9/2016 22:43 | 277° | 16.1 | -165° | 7 | Code0 | 083° | 42.09 | 1005.4 | 51 11.964n | 021 05.705w | ||
| 6/10/2016 4:56 | 272° | 12.7 | 171° | 6.5 | Code0 | 102° | 50.81 | 1005.2 | 51 23.580n | 020 01.002w | ||
| 6/10/2016 12:46 | 266° | 7.8 | 176° | 6.5 | Engine | 090° | 44.53 | 1005.5 | 51 20.350n | 018 39.788w | ||
| 6/10/2016 19:42 | 277° | 5.2 | -173° | 6.3 | Engine | 090° | 44.59 | 1005.5 | 51 26.194n | 017 29.048w | ||
| 6/11/2016 2:41 | 050° | 4 | -40° | 6.4 | Engine | 090° | 44.62 | 1005.8 | 51 31.591n | 016 17.980w | ||
| 6/11/2016 9:44 | 068° | 9.5 | -28° | 6.3 | Engine | 096° | 47.46 | 1006.4 | 51 36.565n | 015 06.644w | ||
| 6/11/2016 17:16 | 065° | 8.8 | -24° | 6.3 | Engine | 089° | 44.61 | 1007.3 | 51 36.955n | 013 50.224w | ||
| 6/12/2016 0:19 | 045° | 8 | -39° | 6.4 | Engine | 084° | 42.55 | 1008.4 | 51 41.870n | 012 38.750w | ||
| 6/12/2016 7:01 | 025° | 6.6 | -54° | 6.4 | Engine | 079° | 40.58 | 1009.9 | 51 49.760n | 011 31.187w | ||
| 6/12/2016 13:19 | 017° | 5.6 | -40° | 6.4 | Engine | 057° | 4.71 | 1010.5 | 52 00.647n | 010 27.809w | ||
| 6/12/2016 14:04 | 018° | 5.5 | -39° | 6.4 | Engine | 057° | 4.71 | 1010.6 | 52 03.517n | 010 21.742w | ||
| 6/12/2016 14:48 | 019° | 5.5 | 6° | 6.4 | Engine | 013° | 0.39 | 1010.6 | 52 06.381n | 010 15.662w | ||
| 6/12/2016 14:51 | 019° | 5.5 | 6° | 6.4 | Engine | 013° | 0.39 | 1010.6 | 52 06.771n | 010 15.571w | ||
| 6/12/2016 14:55 | 019° | 5.5 | 6° | Engine | 013° | 1010.6 | 52 07.161n | 010 15.480w | ||||
| Route distance | 2680.26nm | |||||||||||
| Optimal distance | 2840.64nm | |||||||||||
| Optimal route time | 15d 05h 25m |
It is of course a lot of data to try to digest, but you can see that there will be a bit of motor sailing at the beginning, then a few days of motoring at the end as the wind is predicted to drop. Of course forecasts 12+ days in advance so you can't read too much into the last 4-5 days of the prediction. The notes at the end show the route distance (following ken's waypoint) of 2480nm but is suggesting the boat travel 2840nm to get to the destination fastest. Finally is predicts the passage will take just over 15 days. As looking at tables of data is not that helfpul in terms of understanding what the program is telling you, it plots your route graphically including the predicted conditions (wind barbs) along your way. Below is the predicted route:
The Black line with white dots is the route given by Ken (discussed yesterday) and the Red line is the route Expedition suggests. As you can see the Expedition route goes through each white dot as we have told the program to follow that route to make sure it keeps the boat out of the ice zone. They are a little small, but you can see the red wind barbs along the route. Each one shows what the wind is predicted to do when the boat is at that location (long barbs are 10kts, short barbs are 5 kts, so a long barb with a short barb predicts about 15 kts and the direction of the barbs shows predicted wind direction.
Here is a zoomed in view which has also been "advanced" in time to show the overall weather prediction for Saturday June 4th. It is a little hard to see, but the predicted position of the boat at this time is shown with a red triangle along the red route line. Yoy can see the fairly large low pressure system (black lines are isobar lines, showing the low with a pressure of 996 milibars. The low is positioned North-East of the boats position at that time and you can see the boat will stay on the southern side of the low as it moves north east. This will keep the wind coming from the West as the boat travels East-North-East.
You may be able to now pick out the fact that the wind barbs swing around to the East along the route as the boat approaches Ireland but it should be less than about 10 kts. This is why the program suggests it may be neccesary to motor sail the last few days if the weather forecast doesn't change.
Bill will download new weather files each day and re-run the prediction based on the actual position of the boat and updated weather data. If the boat goes faster or slower than expected, or the weather forecast changes, then the program will adjust it's prediction accordingly. We don't blindly follow the suggestion of the algorithm, but have learned to let it help you process all the weather data and combine that with suggestions and information provided by Locus Weather to try to find the best, fastest, and/or most comfortable route along a passage.
It takes a little time to become proficient with Expedition and taking the time to refine the polar performance data was a big step in making the optimal routing more effective and helpful, but we find the software extremely valuable in improving passage speed and comfort and reducing the time it takes to process the trove of weather data that is available today.
If I have a few minutes tomorrow or in a few days, I will discuss a little bit about how it is we get that weather data when offshore, and I am sure we will hear from Bill in the morning as well, so stay tuned.
-- Gram
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