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We arrived by train at Grünau im Almtal where we waited a few minutes for the bus.
Bild 1: Altocumulus castellanus (lower part of the photograph)
I just talked to the other participants about preceding clouds before thunderstorm events during the train ride. And then I could actually show them textbook mid-level clouds with several little towering updrafts, indicating the aforementioned mid-level instability.
Bild 2: After a few minutes ride with the bus, we eventually arrived at our starting point.
While the bus continued on to the Almsee, we headed into a side valley called Hetzau. Motorized hikers could drive up the valley as far as the Almtaler Haus, so for the first kilometres we followed an asphalt road where cars were speeding around the bends - making it a rather hazardous and annoying stretch. Still it was an ideal part to get to know eachother and to warm up before the more serious part of the hike began.
Bild 3: Mücken-Händelwurz (Gymnadenia conopsea)
The Hetzau valley is filled with gravel banks formed by a post-glacial rockslide. The 12km tongue of detritus is one of the longest of its kind in the Eastern Alps. It creates ideal conditions for a wide variety of Orchis species to thrive. I also spotted dozens of Neottia ovata (Großes Zweiblatt) but it's difficult to photograph well.
Bild 4: Probably Geflecktes Knabenkraut (Dactylorhiza maculata), could also be fuchsii.
Bild 5: Crossing the Straneggbach, with crystal clear water.
Zwillingkogel (2184m) in the background.
After we arrived at Almtaler Haus, we had a nice lunch break with Kaspressknödelsuppe, big salad and other good-looking meals. In fact, some cumulus clouds gathered over the Welser Hütte and beyond, partially obscuring the nearby mountains. I even observed a well-developed cumulus congestus cloud, though it never managed to evolve into a cumulonimbus cloud, the type associated with showers and thunderstorms.
Weather Balloon Ascent Graz, 05 lct.
The graph shows the temperature (x-axis) and height (y-axis, in km and hPa) of measured temperatur (red) and dewpoint (green) in Graz, Styria. The vertical profile is supposed to be representative of the prevailing air mass over Central Austria. The marked area shows sufficient mid-level instability (read area) to sustain a convective updraft, like in form of a cumulus cloud. The updraft is limited to 5km altitude, with very dry air aloft (distance of red and green line is very big, meaning very dry air). The cloud base started at about 2km altitude, i.e. elevated convection, with a distinct temperature inversion between the surface and the cloud base. In simplified terms: The surface layer was stable, and mid-levels unstable, with stable upper-levels again. For that reason, the cumulus cloud couldn't develop into a thunderstorm.
On the right, wind direction and speed is displayed with wind barbs. Here strong northwesterly winds prevailed in the layer where convective clouds have formed.
Satellite Image at 11.40 lct:
This relatively new satellite product, thanks to the next satellite generation being active since this year, shows visible clouds and their phase, i.e. whether they contain liquid (supercooled) water, mixed phase (liquid water and ice crystals, graupel) or only ice crystals (like high clouds or thunderstorm clouds). Ochre color means liquid water particles while pink color indicates the mixed phase and deeper clouds (i.e. reaching greater vertical length).
At the time as we arrived at Almtaler Haus, a few pink spots moved just south of the Tote Gebirge southeastward (northwesterly flow), indicating weak mid-level convection. None of these clouds managed to evolve into a thunderstorm and convective activity later decreased during the day.
To sum up: Mid-level clouds may serve as a sign for deep-moist convection but they are not always a sign for upcoming thunderstorms. It strongly depends on the depth of the unstable layer (here: only between 2 and 5km) as well as a necessary trigger like increasing low pressure influence (here: the opposite took place as a high pressure system approached from the west).
Bild 6: Center: Schermberg (2396m), left (in clouds): Brotfall (2380m), right: Pfaffenschneid (2222m) and Hetzaugraben
The Welser Höhenweg (Ausseer Weg) tangents at the upper part of the Hetzaugraben between Welser Hütte and Pühringer Hütte. The Welser Hütte is situated to the left of the Schermberg.
Bild 7: Dry creek.
Bild 8: Approaching the steep slope where the hiking trail leads to the Welser Hütte.
The cumulus clouds started to break up and decrease in the next two hours. Nevertheless I was rather happy about the shadow during noon.
Bild 9: Rock gorge originating from Zwillingkogel (2184m).
The trail takes a turn to the right here.
Bild 10: While waiting for all participants to catch up, we were impressed by the surrounding landscape.
Bild 11: Like the mountain ridge stretching from Hochplattenkogel to Fäustling.
Bild 12: Fixed cable for a safe pass of this exposed part of the trail at the beginning.
Bild 13: So-called Hans-Pumberger Band, a metal ladder with fixed cable overcoming the slope.
Bild 14: Hetzau valley, with Kasberg (1747m) in the center, and Traunstein (1691m) to the left far beyond.
Actually the rockslide causing the tongue of debris alongside the Hetzau valley is quite interesting. Its origin is still not entirely explained. A 2003 publication hypothesized the origin in the area of Kreuz (2174m) and Zwillingkogel. The event created so-called Toma hills, isolated hilly-like and symmetric accumulation of rock debris in a plain. Another interesting feature of the valley are the Ödseen, small-scale lakes remaining from the Würm-Kaltzeit after the glaciers retreated.
Bild 15: Nice bench with a view in front of a big rock, with Kreuz (2174m) behind.
Bild 16: Impressive northern wall of Kreuz, also called Rasengipfel in older maps.
Bild 17: The trail crossed a rockfall area with big stones.
Bild 18: Typical bands of limestone for the Totes Gebirge.
Bild 19: Likely the crux of the entire trail: a vertical and somewhat bended old ladder.
The ladder rungs waggled during the climb but were still fixed. So the main difficulty here was to have enough faith that the rungs didn't unscrew during the climb. I would classify this part as A/B therefore.
Bild 20: Looking down the ladder after I had a fixed stance again.
- Track: Habernau Hst. (577m, 10.20) - Almtaler Haus (714m, 11.40-12.20) - Steig-Beginn (13.30) - Welser Hütte (1726m, 15.45).
- Distance: 12,5 km
- Height Metres (upward): 1160 hm
- Net Walking Time: 4 hrs 15 min (estimated)
We arrived by train at Grünau im Almtal where we waited a few minutes for the bus.
Bild 1: Altocumulus castellanus (lower part of the photograph)
I just talked to the other participants about preceding clouds before thunderstorm events during the train ride. And then I could actually show them textbook mid-level clouds with several little towering updrafts, indicating the aforementioned mid-level instability.
Bild 2: After a few minutes ride with the bus, we eventually arrived at our starting point.
While the bus continued on to the Almsee, we headed into a side valley called Hetzau. Motorized hikers could drive up the valley as far as the Almtaler Haus, so for the first kilometres we followed an asphalt road where cars were speeding around the bends - making it a rather hazardous and annoying stretch. Still it was an ideal part to get to know eachother and to warm up before the more serious part of the hike began.
Bild 3: Mücken-Händelwurz (Gymnadenia conopsea)
The Hetzau valley is filled with gravel banks formed by a post-glacial rockslide. The 12km tongue of detritus is one of the longest of its kind in the Eastern Alps. It creates ideal conditions for a wide variety of Orchis species to thrive. I also spotted dozens of Neottia ovata (Großes Zweiblatt) but it's difficult to photograph well.
Bild 4: Probably Geflecktes Knabenkraut (Dactylorhiza maculata), could also be fuchsii.
Bild 5: Crossing the Straneggbach, with crystal clear water.
Zwillingkogel (2184m) in the background.
After we arrived at Almtaler Haus, we had a nice lunch break with Kaspressknödelsuppe, big salad and other good-looking meals. In fact, some cumulus clouds gathered over the Welser Hütte and beyond, partially obscuring the nearby mountains. I even observed a well-developed cumulus congestus cloud, though it never managed to evolve into a cumulonimbus cloud, the type associated with showers and thunderstorms.
Weather Balloon Ascent Graz, 05 lct.
The graph shows the temperature (x-axis) and height (y-axis, in km and hPa) of measured temperatur (red) and dewpoint (green) in Graz, Styria. The vertical profile is supposed to be representative of the prevailing air mass over Central Austria. The marked area shows sufficient mid-level instability (read area) to sustain a convective updraft, like in form of a cumulus cloud. The updraft is limited to 5km altitude, with very dry air aloft (distance of red and green line is very big, meaning very dry air). The cloud base started at about 2km altitude, i.e. elevated convection, with a distinct temperature inversion between the surface and the cloud base. In simplified terms: The surface layer was stable, and mid-levels unstable, with stable upper-levels again. For that reason, the cumulus cloud couldn't develop into a thunderstorm.
On the right, wind direction and speed is displayed with wind barbs. Here strong northwesterly winds prevailed in the layer where convective clouds have formed.
Satellite Image at 11.40 lct:
This relatively new satellite product, thanks to the next satellite generation being active since this year, shows visible clouds and their phase, i.e. whether they contain liquid (supercooled) water, mixed phase (liquid water and ice crystals, graupel) or only ice crystals (like high clouds or thunderstorm clouds). Ochre color means liquid water particles while pink color indicates the mixed phase and deeper clouds (i.e. reaching greater vertical length).
At the time as we arrived at Almtaler Haus, a few pink spots moved just south of the Tote Gebirge southeastward (northwesterly flow), indicating weak mid-level convection. None of these clouds managed to evolve into a thunderstorm and convective activity later decreased during the day.
To sum up: Mid-level clouds may serve as a sign for deep-moist convection but they are not always a sign for upcoming thunderstorms. It strongly depends on the depth of the unstable layer (here: only between 2 and 5km) as well as a necessary trigger like increasing low pressure influence (here: the opposite took place as a high pressure system approached from the west).
Bild 6: Center: Schermberg (2396m), left (in clouds): Brotfall (2380m), right: Pfaffenschneid (2222m) and Hetzaugraben
The Welser Höhenweg (Ausseer Weg) tangents at the upper part of the Hetzaugraben between Welser Hütte and Pühringer Hütte. The Welser Hütte is situated to the left of the Schermberg.
Bild 7: Dry creek.
Bild 8: Approaching the steep slope where the hiking trail leads to the Welser Hütte.
The cumulus clouds started to break up and decrease in the next two hours. Nevertheless I was rather happy about the shadow during noon.
Bild 9: Rock gorge originating from Zwillingkogel (2184m).
The trail takes a turn to the right here.
Bild 10: While waiting for all participants to catch up, we were impressed by the surrounding landscape.
Bild 11: Like the mountain ridge stretching from Hochplattenkogel to Fäustling.
Bild 12: Fixed cable for a safe pass of this exposed part of the trail at the beginning.
Bild 13: So-called Hans-Pumberger Band, a metal ladder with fixed cable overcoming the slope.
Bild 14: Hetzau valley, with Kasberg (1747m) in the center, and Traunstein (1691m) to the left far beyond.
Actually the rockslide causing the tongue of debris alongside the Hetzau valley is quite interesting. Its origin is still not entirely explained. A 2003 publication hypothesized the origin in the area of Kreuz (2174m) and Zwillingkogel. The event created so-called Toma hills, isolated hilly-like and symmetric accumulation of rock debris in a plain. Another interesting feature of the valley are the Ödseen, small-scale lakes remaining from the Würm-Kaltzeit after the glaciers retreated.
Bild 15: Nice bench with a view in front of a big rock, with Kreuz (2174m) behind.
Bild 16: Impressive northern wall of Kreuz, also called Rasengipfel in older maps.
Bild 17: The trail crossed a rockfall area with big stones.
Bild 18: Typical bands of limestone for the Totes Gebirge.
Bild 19: Likely the crux of the entire trail: a vertical and somewhat bended old ladder.
The ladder rungs waggled during the climb but were still fixed. So the main difficulty here was to have enough faith that the rungs didn't unscrew during the climb. I would classify this part as A/B therefore.
Bild 20: Looking down the ladder after I had a fixed stance again.
Aber gut, in der Gruppe und gut gelaunt ist es vielleicht wirklich halb so wild.
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