Ask a Climatologist: An Alaska-sized storm sets record
By Casey Grove, Alaska Public Media - Anchorage
-January 13, 2021
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The Dec. 31, 2020 “bomb” cyclone over Shemya Island. (Earth.nullschool.net)
At the end of 2020, a massive Aleutian storm set a record for the lowest atmospheric pressure ever recorded in the North Pacific … but you may not have heard about it.
Thankfully, the 60-foot seas and 80 mph winds were hundreds of miles from most Alaskans. But what does it actually mean for there to be an area of extreme low pressure?
National Weather Service climate researcher Brian Brettschneider spoke with Alaska Public Media’s Casey Grove to explain.
We have seen the year 2020 was, weatherwise, a remarkable and deadly year by various extreme weather events. Including the record-breaking Atlantic hurricane season, wildfires in Siberia, and winter storms in both Europe and the United States. And the year ended with a bang, setting a new North Pacific low-pressure record of 921 mbar as a powerful extratropical storm hit Alaska on the last day of 2020. While just a day earlier, a new world record for high-pressure has been set in Mongolia, 1094 mbar!
As we have been writing about in our initial Wednesday’s discussion regarding the potential record-breaking evolution of this storm, the North Pacific, Alaska, and the Bering Sea have set a new record for the lowest central pressure of an extratropical storm. The lowest central pressure with this storm was 921 mbar over the North Pacific on the last day of 2020, Dec 31st.
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While the center of the low crossed the Aleutian Islands, the nearest weather station Shemya island of the Alaska weather station network recorded 924.8 mbar, breaking the previous record of 926 mbar set at Dutch Harbor on October 25th, 1977.
When the system moved into the Bering Sea, it also set a new minimum central pressure of 921 mbar, becoming the deepest storm in the Bering Sea on record. The last storm with so deep pressure were remnants of Super Typhoon Nuri.
The North Pacific hardly sees any rest this winter and this storm was no exception for the region. A combination of the deep Arctic cold over Siberia, the advection of a warm Pacific tropical air mass, and the extremely powerful 250 mph jet stream between these two air masses have resulted in a very *explosive* development of an extratropical storm and bottom out at 921 mbar, right in the time the storm was about to cross the Aleutian Islands.
By Casey Grove, Alaska Public Media - Anchorage
-January 13, 2021
The Dec. 31, 2020 “bomb” cyclone over Shemya Island. (Earth.nullschool.net)At the end of 2020, a massive Aleutian storm set a record for the lowest atmospheric pressure ever recorded in the North Pacific … but you may not have heard about it.
Thankfully, the 60-foot seas and 80 mph winds were hundreds of miles from most Alaskans. But what does it actually mean for there to be an area of extreme low pressure?
National Weather Service climate researcher Brian Brettschneider spoke with Alaska Public Media’s Casey Grove to explain.
We have seen the year 2020 was, weatherwise, a remarkable and deadly year by various extreme weather events. Including the record-breaking Atlantic hurricane season, wildfires in Siberia, and winter storms in both Europe and the United States. And the year ended with a bang, setting a new North Pacific low-pressure record of 921 mbar as a powerful extratropical storm hit Alaska on the last day of 2020. While just a day earlier, a new world record for high-pressure has been set in Mongolia, 1094 mbar!
As we have been writing about in our initial Wednesday’s discussion regarding the potential record-breaking evolution of this storm, the North Pacific, Alaska, and the Bering Sea have set a new record for the lowest central pressure of an extratropical storm. The lowest central pressure with this storm was 921 mbar over the North Pacific on the last day of 2020, Dec 31st.
While the center of the low crossed the Aleutian Islands, the nearest weather station Shemya island of the Alaska weather station network recorded 924.8 mbar, breaking the previous record of 926 mbar set at Dutch Harbor on October 25th, 1977.
When the system moved into the Bering Sea, it also set a new minimum central pressure of 921 mbar, becoming the deepest storm in the Bering Sea on record. The last storm with so deep pressure were remnants of Super Typhoon Nuri.
The North Pacific hardly sees any rest this winter and this storm was no exception for the region. A combination of the deep Arctic cold over Siberia, the advection of a warm Pacific tropical air mass, and the extremely powerful 250 mph jet stream between these two air masses have resulted in a very *explosive* development of an extratropical storm and bottom out at 921 mbar, right in the time the storm was about to cross the Aleutian Islands.