WeatherExtreme Forecast Discussion July 31, 2017 0650Z

Monday and Tuesday should be generally favorable for wave flying. There may be high overcast at FL300, but otherwise generally cloud-free at lower levels. Some waves should be present each, but vertical velocities will not be as great as previously forecast and will be in the range of 600–1200 fps below FL 200. Winds aloft will be from the west-southwest on Monday, becoming more westerly on Tuesday. It may be difficult to find vertical velocities above 800 fps on Tuesday above FL 180 as the waves propagate eastward and dissipate.

Weather Extreme Forecast Discussion #8 7/25 1520Z

A “balmy” day today in El Calafate with temperatures reaching the low 40’s. Winds generally 10 to 15 kts and variable in direction at the surface. Above FL100 expect winds to be generally 50+ kts from the northwest. The upper reaches of Lago Argentino, near 50S 72.3W should be favorable for wave, but it will be challenging to get to FL200, with a high thin overcast.Wednesday should be a down day with clouds and rain.

WeatherExtreme Forecast Discussion #7 7/23 0535Z

Forecast for Monday is for a few snow flurries in the pre-dawn hours. The afternoon will have scattered mid- to high-level clouds during the afternoon, but dry with high temperatures near or just above freezing. Winds generally northerly and light at El Calafate. More extensive clouds over the mountain ridge line with some snow or drizzle persisting through the afternoon. Winds aloft generally westerly and > 50 kts above FL90. Tuesday afternoon will bring scattered low- to mid-level clouds with high overcast and some light drizzle at El Calafate. Winds aloft from the northwest from 50-80 kts.

WRF is still down due to NCEP changes in GFS files, but a fix may be available Monday.

WeatherExtreme Forecast Discussion #5 July 19, 2017

Temperatures will struggle to get above freezing in El Calafate over the next 5 days, with some light rain falling late this afternoon and overnight, and again during the early morning hours Friday, when some of it may fall as snow flurries. Conditions are not conducive to flying today and Thursday. There is possibly an opportunity for flight testing on Friday afternoon, but it probably won’t be great. Saturday may be better, but there are fairly large model differences at the moment.