![\"View](\"https:\/\/flyfiesch.com\/wp-content\/uploads\/2014\/06\/Haslital-2.jpg\")
<\/a>View of the Haslital from the end of the Goms, looking north<\/p><\/div>\n
This wind will nearly always develop on flyable days.\u00a0\u00a0However, with south overpressure<\/a>, or a general meteo wind from between south-east and west, it may well be absent in the morning, and only blow relatively weakly in the afternoon. Conversely, with north overpressure, a general airflow from between north and east, or\u00a0in Bise<\/a> conditions, it is likely to arise early and have a significant effect on flying conditions.\u00a0 Furthermore, the same meteo situation will tend to be associated with a much stronger wind in the spring than in late summer. As you fly up the Goms, it may be associated with a drift on the thermals from the north, streams of descending flow, variations in your ground speed, or an increasing headwind. Conversely, if you can get above the spine of the main ridge, you may find buoyant conditions there as the northerly flow leads to gently rising air or even thermals coming up the north-facing aspect in combination with the anabatic flow on the sunnier south-facing side. Unless you intend to cross the Grimsel Pass, it can be simply avoided, by staying high and heading away from the valley towards the higher slopes as you get near. Otherwise, if you are too low and too far out, you may find yourself caught in a sudden rough headwind being flushed down into significant leeside turbulence behind one of the spines running up the slope. Also, once you have reached its zone of influence, you will often find a blue gap or rapidly evaporating clouds, where thermals are suppressed by the general downward airflow which it causes.<\/p>\n Grimselschlange viewed from the Belvedere hotel, beside the Rh\u00f4ne Glacier, looking west<\/p><\/div>\n As the Grimseler descends into the Goms, it swerves to the right to blow down the valley from the north-east, and often gusts around 50km\/hr in Oberwald.\u00a0 Further down the valley, e.g. at the Ritzingen landing field<\/a>, the breeze will often reach 30 km\/hr in the afternoon, but the flow is usually laminar here.\u00a0 Although generally viewed as a negative feature, it actually helps to trigger thermals by undercutting the warmer air in the valley, and towards the upper end of the Goms it\u00a0may sometimes\u00a0be used to slope soar and reconnect with thermals if you get low.\u00a0 It can also produce widespread convergence lift where it meets the southwesterly valley breeze coming up from Brig \u2013 a nightmare if you want to get down, but a delight\u00a0if you succeed in finding it when needing a low save in the afternoon.\u00a0 You can also see a short video version<\/a> of the picture above (i.e. the Grimselschlange viewed from the east).<\/p>\n When you intend to fly a triangle and start to feel the effects of this wind at the upper end of the Goms, it can be a tricky decision to decide how far to the east to persist for your turnpoint. In the example below, I pushed a bit too hard, and nearly ended up getting decked as a result.<\/p>\n Escaping from the Grimseler (click here<\/a> for 3D visualisation, here<\/a> for XContest details)<\/p><\/div>\n Note how the thermals when approaching the end of the Goms with plenty of height appear to be more or less vertical (though somewhat fragmented), but once I am lower down, my climbs show a substantial drift from the east.<\/p>\n However, the Grimseler can also become your friend, e.g. if you have failed to find lift in the Grimsel\/Furka area, enabling you to soar up from relatively low, to the south of Oberwald, and continue your flight along the north-facing side of the Goms, rather than bombing out, as in this example:<\/p>\n Soaring in the Grimseler to the south of Oberwald (click here<\/a> for 3D visualisation, here<\/a> for XContest details)<\/p><\/div>\n You can see that I reach the slope about 400m above the valley floor, and start by S turning, but am soon able to 360 in a thermal and climb out.\u00a0 Obviously this is likely to work better later in the day than earlier.<\/p>\n Very occasionally the Grimseler can trigger a substantial climb, in this case at around 4pm from below 2,000m to nearly 4,000m:<\/p>\n 2,000m climb in the Grimseler (click here<\/a> and >> to 6:06:00 for 3D visualisation, here<\/a> for XContest details)<\/p><\/div>\n","protected":false},"excerpt":{"rendered":" A very important local feature is the cold wind which pushes up the Haslital from the north-west and blows through the Grimsel Pass into the Goms.\u00a0 It’s often referred to as the \u201cGrimselschlange\u201d (\u201cSchlange\u201d meaning \u201csnake\u201d), but some say this … Continue reading <\/a><\/a><\/a><\/a>