Article written for EarthSky by meteorologist Rachel Duensing.
An Alberta Clipper is a fast-moving low pressure system that moves out of west-central Canada and, typically, skirts across North America’s Great Lakes. It brings cold weather and, if conditions are right, snow. A clipper developed in central Alberta this week and quickly moved southeast toward the Great Lakes. As it’s been moving over the Great Lakes – headed toward the U.S. Northeast today (December 4, 2024) – the chances for snow have been going up.
Plus, there might be another clipper to watch in the coming week. It’s called the Panhandle Hooker, and it’s just as complex – if not more so – than its Canadian neighbor, the Alberta Clipper. Sometimes called a Texas Hooker, the Panhandle Hooker is another fast-moving low pressure system that gets its name from the region where it develops: the Panhandles of Texas and Oklahoma.
A Panhandle Hooker hasn’t yet developed. But global forecasting models are suggesting one could develop early in the week of December 9. What happens after that, if it develops, is still to be determined … as the timing of cold air is vital for snow formation with the hookers.
National Weather Service forecast
As of 2:52 a.m. EST (6:52 UTC) on December 4, the National Weather Service Prediction Center in College Park, Maryland was saying:
A strengthening clipper storm will shift across southeastern Canada Wednesday and Thursday with an arctic cold front crossing the Great Lakes and Northeast which will produce intense bursts of snow and gusty winds. Localized short-duration blizzard conditions will be possible with several feet of additional lake effect snow in the Great Lakes. Dry and warm conditions are expected in the West.
And the NWS was calling for:
…Heavy snow for the Upper Peninsula of Michigan and the northern Lower Peninsula on Wednesday…
…Heavy lake-enhanced snow downwind from Lakes Erie and Ontario on Wednesday and Thursday; Heavy snow over parts of Northern New England; light to moderate snow over parts of the Central Appalachians on Wednesday…
What is an Alberta Clipper?
A clipper on its own won’t bring snow. Several conditions have to be in place, and one of those conditions is cold air. On Sunday and Monday – December 2 and 3 – cold high pressure moved south from Canada and settled into the United States. Wind around a high pressure zone flows clockwise (or anticyclonic). So as the high pressure moved southeast, winds around the high pressure zone came out of the south. In the Northern Hemisphere, these winds can bring in just enough moisture to fuel a chance for snow.
So the ingredients are prepared: cold air, moisture, and a racing Alberta Clipper to help create the chance for wintry precipitation.
Because clippers are fast moving systems, they tend to drop some snow before quickly moving on. But in this instance, the snow from the clipper is just the beginning.
By Thursday, the Alberta Clipper will be moving through southern Ontario, northern New York and southern Quebec. As cold wind moves over the (relatively) warm waters of the Lakes, the warmer, moister air will rise, condensing into clouds in the process. Precipitation will form and fall out of the clouds, and due to the cold air in place anything that falls out of the clouds will be in the form of snow.
Lake-effect snow bands can be persistent and impactful, sometimes dropping up to 3 inches (8 centimeters) of snow per hour! With this lake-effect snow event, parts of Michigan’s Upper Peninsula are expecting 10 to 16 inches (25 to 41 centimeters) of snow through Thursday night. Other communities near the Great Lakes – like Cleveland, Ohio and Erie, Pennsylvania – expect an additional 2 to 4 inches thanks to lake-effect snow.
Another clipper system: The Panhandle Hooker
Here’s another clipper-type system to watch in the coming week. Panhandle Hookers can be complex storm systems. Despite forming in the southern United States, as the name implies, this low pressure zone doesn’t stay there. It eventually “hooks” quickly to the northeast, where impacts are felt in a variety of ways on its path.
As it develops farther south, a Panhandle Hooker has the advantage of warmer, moister air feeding into it from the Gulf of Mexico. The higher moisture content gives it a better chance to produce significant precipitation in many different forms, depending on the conditions.
During the winter, and especially when cold air has spilled south from Canada, these hookers can tap into that cold air and produce snow – sometimes heavy – on the northern side of the low pressure zone. On the southern side of the low pressure zone is where things can be more interesting, as this area is typically warmer for Panhandle Hookers. Strong, cold air crashing in when warmer air is in place is a recipe for thunderstorms, some of which can be severe! It’s not uncommon for snow to fall north of severe thunderstorms in winter, as the complex nature of low pressure systems interact with the different temperatures across the country.
As winter goes on, these systems with unique names are sure to keep us all on our toes, as we prepare for whatever the weather throws at us.
Bottom line: An Alberta Clipper developed in Canada this week and quickly moved southeast toward the Great Lakes. Meanwhile, the chances for snow have been going up.
The post Alberta Clipper, Panhandle Hooker, and snow, snow, snow first appeared on EarthSky.
from EarthSky https://ift.tt/G9huwjx
Article written for EarthSky by meteorologist Rachel Duensing.
An Alberta Clipper is a fast-moving low pressure system that moves out of west-central Canada and, typically, skirts across North America’s Great Lakes. It brings cold weather and, if conditions are right, snow. A clipper developed in central Alberta this week and quickly moved southeast toward the Great Lakes. As it’s been moving over the Great Lakes – headed toward the U.S. Northeast today (December 4, 2024) – the chances for snow have been going up.
Plus, there might be another clipper to watch in the coming week. It’s called the Panhandle Hooker, and it’s just as complex – if not more so – than its Canadian neighbor, the Alberta Clipper. Sometimes called a Texas Hooker, the Panhandle Hooker is another fast-moving low pressure system that gets its name from the region where it develops: the Panhandles of Texas and Oklahoma.
A Panhandle Hooker hasn’t yet developed. But global forecasting models are suggesting one could develop early in the week of December 9. What happens after that, if it develops, is still to be determined … as the timing of cold air is vital for snow formation with the hookers.
National Weather Service forecast
As of 2:52 a.m. EST (6:52 UTC) on December 4, the National Weather Service Prediction Center in College Park, Maryland was saying:
A strengthening clipper storm will shift across southeastern Canada Wednesday and Thursday with an arctic cold front crossing the Great Lakes and Northeast which will produce intense bursts of snow and gusty winds. Localized short-duration blizzard conditions will be possible with several feet of additional lake effect snow in the Great Lakes. Dry and warm conditions are expected in the West.
And the NWS was calling for:
…Heavy snow for the Upper Peninsula of Michigan and the northern Lower Peninsula on Wednesday…
…Heavy lake-enhanced snow downwind from Lakes Erie and Ontario on Wednesday and Thursday; Heavy snow over parts of Northern New England; light to moderate snow over parts of the Central Appalachians on Wednesday…
What is an Alberta Clipper?
A clipper on its own won’t bring snow. Several conditions have to be in place, and one of those conditions is cold air. On Sunday and Monday – December 2 and 3 – cold high pressure moved south from Canada and settled into the United States. Wind around a high pressure zone flows clockwise (or anticyclonic). So as the high pressure moved southeast, winds around the high pressure zone came out of the south. In the Northern Hemisphere, these winds can bring in just enough moisture to fuel a chance for snow.
So the ingredients are prepared: cold air, moisture, and a racing Alberta Clipper to help create the chance for wintry precipitation.
Because clippers are fast moving systems, they tend to drop some snow before quickly moving on. But in this instance, the snow from the clipper is just the beginning.
By Thursday, the Alberta Clipper will be moving through southern Ontario, northern New York and southern Quebec. As cold wind moves over the (relatively) warm waters of the Lakes, the warmer, moister air will rise, condensing into clouds in the process. Precipitation will form and fall out of the clouds, and due to the cold air in place anything that falls out of the clouds will be in the form of snow.
Lake-effect snow bands can be persistent and impactful, sometimes dropping up to 3 inches (8 centimeters) of snow per hour! With this lake-effect snow event, parts of Michigan’s Upper Peninsula are expecting 10 to 16 inches (25 to 41 centimeters) of snow through Thursday night. Other communities near the Great Lakes – like Cleveland, Ohio and Erie, Pennsylvania – expect an additional 2 to 4 inches thanks to lake-effect snow.
Another clipper system: The Panhandle Hooker
Here’s another clipper-type system to watch in the coming week. Panhandle Hookers can be complex storm systems. Despite forming in the southern United States, as the name implies, this low pressure zone doesn’t stay there. It eventually “hooks” quickly to the northeast, where impacts are felt in a variety of ways on its path.
As it develops farther south, a Panhandle Hooker has the advantage of warmer, moister air feeding into it from the Gulf of Mexico. The higher moisture content gives it a better chance to produce significant precipitation in many different forms, depending on the conditions.
During the winter, and especially when cold air has spilled south from Canada, these hookers can tap into that cold air and produce snow – sometimes heavy – on the northern side of the low pressure zone. On the southern side of the low pressure zone is where things can be more interesting, as this area is typically warmer for Panhandle Hookers. Strong, cold air crashing in when warmer air is in place is a recipe for thunderstorms, some of which can be severe! It’s not uncommon for snow to fall north of severe thunderstorms in winter, as the complex nature of low pressure systems interact with the different temperatures across the country.
As winter goes on, these systems with unique names are sure to keep us all on our toes, as we prepare for whatever the weather throws at us.
Bottom line: An Alberta Clipper developed in Canada this week and quickly moved southeast toward the Great Lakes. Meanwhile, the chances for snow have been going up.
The post Alberta Clipper, Panhandle Hooker, and snow, snow, snow first appeared on EarthSky.
from EarthSky https://ift.tt/G9huwjx
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