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Post by desiccatedi85 on May 14, 2024 16:40:20 GMT -5
I was looking at random Japanese climates on the climateatlas.org site and noticed that Japan's meteorological service provides data for most stations with thunder days per month which tommyFL was smart to include in these clickable weatherboxes. Everyone on here likely knows about Western Japan's extreme snowfall and rainfall amounts especially relative to the temps, but what caught my attention was the high amounts of thunder days in these cold, stable winter climates along the Sea of Japan. January is usually the 2nd or 3rd most thundery month in these places, with only December and sometimes November being marginally more thundery. Places with milder winters further southwest along the Sea of Japan coast (south and west of Tsuruga) don't get such high averages for winter thunder days, there is a drop-off, with temps increasing a bit.
Average high/low figures and thunder days at stations near the Sea of Japan in January, the coldest month (1991-2020 data)
Sakata = 40ºF/31ºF with 4.5 thunder days
Takada = 43ºF/31ºF with 6.5 thunder days Niigata = 42ºF/32ºF with 4.5 thunder days Kanzawa = 45ºF/34ºF with 7.9 thunder days Wajima = 44ºF/33ºF with 4.7 thunder days Akita = 38ºF/28ºF with 3.4 thunder days Fukui = 44ºF/33ºF with 6.0 thunder days Tsuruga = 46ºF/35ºF with 5.7 thunder days
These numbers are impressive, as is the fact that thunder is most common in winter in these places despite them having plentiful summer rain as well. In the notoriously thundery US Midwest, these averages would be found in spring/summer months with far warmer temps. Even the US South and West, much milder during winter, cannot compare in terms of thunder days. I know thunder days averages are not widespread, but are there other places that get so many cold thunderstorms?
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Post by srfoskey on May 14, 2024 19:48:18 GMT -5
My impression of lake effect precipitation is that it is enhanced by convective instability. Thus, the fact that coastal Japan gets a lot of thunder days in winter seems physically reasonable. I have not checked atmospheric soundings near the Sea of Japan, but that would be my guess for that effect.
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Post by desiccatedi85 on May 14, 2024 20:29:17 GMT -5
My impression of lake effect precipitation is that it is enhanced by convective instability. Thus, the fact that coastal Japan gets a lot of thunder days in winter seems physically reasonable. I have not checked atmospheric soundings near the Sea of Japan, but that would be my guess for that effect. Do the Great Lakes lake-effect belts in the US and Canada get similar amounts of thunder during the late fall and winter? I knew that lake-effect is convective driven but it seems this is even more pronounced in western Japan. |
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Post by srfoskey on May 15, 2024 0:58:17 GMT -5
My impression of lake effect precipitation is that it is enhanced by convective instability. Thus, the fact that coastal Japan gets a lot of thunder days in winter seems physically reasonable. I have not checked atmospheric soundings near the Sea of Japan, but that would be my guess for that effect. Do the Great Lakes lake-effect belts in the US and Canada get similar amounts of thunder during the late fall and winter? I knew that lake-effect is convective driven but it seems this is even more pronounced in western Japan. Good question, I don't think to the same extent. I'd have to look into what the causes of the differences would be, but maybe it's just that the water-effect precipitation is more extreme off the coast of Japan. |
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Post by MET on May 15, 2024 6:50:13 GMT -5
Japan gets very humid, warm SE winds in summer, and then as the Siberian high forms towards winter, it sends very cold air down over the Sea of Japan, producing instability from the relatively warm sea as the cold air moves atop of it. This produces low top cumulonimbus with low freezing levels that can support lightning in the late autumn/winter months. It is quite an extreme temp contrast as the siberian high develops hence the high number of winter season thunder days. Some other areas can experience this phenomenon, I've seen evidence of Bergen, Norway and other places on the Norway coast getting thundersnow and "lake/ocean effect" type convection from cold airmasses travelling across the relatively warm Atlantic at the same time of year producing "off season" thunderstorm activity.
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Post by Steelernation on May 15, 2024 9:01:08 GMT -5
Do the Great Lakes lake-effect belts in the US and Canada get similar amounts of thunder during the late fall and winter? I knew that lake-effect is convective driven but it seems this is even more pronounced in western Japan. Lmao no |
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Post by massiveshibe on May 15, 2024 10:53:09 GMT -5
Andean highlands get plenty of cold thunderstorms.
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Post by desiccatedi85 on May 15, 2024 17:13:44 GMT -5
Do the Great Lakes lake-effect belts in the US and Canada get similar amounts of thunder during the late fall and winter? I knew that lake-effect is convective driven but it seems this is even more pronounced in western Japan. Lmao no Yeah I didn't think so, but thought it was worth an ask. How common is thunder during winter in these Great Lakes belts? |
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Post by Steelernation on May 15, 2024 20:43:58 GMT -5
Yeah I didn't think so, but thought it was worth an ask. How common is thunder during winter in these Great Lakes belts? Quite rare. Buffalo averages 0.2 thunder dats in January. So maybe one thunderstorm every other year in the absolute most thunder-prone spots. |
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