A New Generation Takes Flight
Note the Weather Station reporting below from the Hood Tech Aero Operations Hangar indicates rooftop wind speed and direction, unobstructed by trees. It typically reports significantly stronger wind than the K4S2 AWOS.
SOARING FORECAST TUTORIAL
There are many websites to help you forecast a good soaring day. The goal of this tutorial is to offer a set of tools to forecast soaring conditions for our local Hood River Valley and mid-Columbia region.
A good starting point is the the National Weather Service (NOAA) 7 day forecast for Hood River as shown in the example below. Soaring conditions are often best the day or two before a weather system and a day or two after, so look for that pattern in the forecast. Check the cloudiness indicator: 65% or less is good. In the drier months the clouds usually stay clear of the ridge. Check the wind: a west wind of 10-15 knots is a good sign. The snow level tells you how to prepare for temps aloft.
The image below is a sample forecast shown for illustration purposes. The highlighted sections all have good soaring potential, especially Saturday, Monday, and Friday because of weather system changes. Click anywhere on the image to open the live NOAA site and see an up-to-date forecast for today.
To find out how well the east ridge is working, use the site below. The surface winds for today are shown. Use the forecast slider at the bottom to look up to 10 days ahead. Click on the wind symbol at top/right, and then use the altitude slider to see how wind prediction varies by altitude. A 10 knot westerly flow at 3000 ft means the ridge will probably be working. Click on the low, med, and high cloud views to see how you might exploit the winds aloft. The height of the thermal boundary layer will determine how high you can climb. If the jet stream is overhead you may find wave. For more features, click here: Windyty Map & Weather Forecast to open the full site.
Click on the image below to see an animated 5 day jet stream forecast. If the jet stream is directly overhead and the air is fairly stable, say cloudiness forecast is 65% or under, there may be wave. If the jet stream is too strong the wave does not work well.
The site embedded below is a sounding plot for this region and is the current forecast. It is best viewed on a desktop computer. Mobile viewers, click WxLoop Hood River to open the plot in a new window. The sounding plot provides a wealth of information about thermal activity, cloud development, winds aloft, how high you can expect to climb, and the potential for wave. Learning how to interpret the sounding plot is a challenging but very worthwhile commitment for glider pilots. While a comprehensive tutorial is beyond the scope of this page, here is a brief guide to reading the chart:
The background graph is formed of static lines, black, green, red, and purple. The horizontal black lines representing different atmospheric pressure levels measured in millibars (mb). Pressure altitude varies but can be roughly viewed as 900MB ~ 2,500', 800MB ~ 5,000', 700MB ~ 10,000', and 500MB ~ 18,000'. The vertical black lines represent temperature gradients in centigrade ranging from -50 to 40 degrees.
Solid green lines are lines of constant potential temperature defined as dry adiabats. Dashed red lines are saturated adiabats. Solid purple lines represent the saturation mixing ratio of the air.
Animated on the background graph are two bold lines, one red and one blue. The blue line represents the dew point of the atmosphere at different levels. The red line represents the environmental air temperature. Both the red and blue lines originate at ground level. Ascending into the atmosphere, if the angle of the environmental air temperature (red line) parallels or leans left of the dry adiabatic lapse rate (green line), that indicates good to better thermal lift. When it angles to the right, that indicates an inversion layer.
Wind barbs in the far right column show speed and direction.