Thursday, October 31, 2019

Does November Weather Deserve Its Bad Reputation?

Jonathan Erdman and Chris DolcePublished: October 30, 2019




When you think of November weather, what crosses your mind?
In 1991, the legendary rock band Guns N' Roses released a song about cold "November Rain."
John Facenda, the iconic voice of NFL Films, once uttered the following in a song simply titled "November":
November can be cold and gray. November can be surly, with bitter rain upon the world and winter coming early.
Since it's the beginning of the handoff between fall and winter, November can be a trying month. But there are also some good aspects of November weather that some can't wait for.
Let's start with November's gloomy aspects.

It Kicks Off the Cloudiest Time of Year, For Some

By November, some in the northern U.S. may have to begin taking their vitamin D supplement.
It's typically the cloudiest month of the year in parts of the northern Plains and upper Midwest, including the Twin Cities and Milwaukee, Wisconsin, according to Alaska-based climatologist Brian Brettschneider.
In other parts of the Midwest and interior Northeast, that cloudy peak arrives in December, but November kicks it off.
An average November sky is at least 70% cloud-covered around the Great Lakes, interior Northeast and Pacific Northwest.
This map shows the average November cloudiness from 1966 to 1996.

The Season's First Measurable Snow Arrives For Many

For many cities in the Northeast, Midwest and West, the average first measurable snow – defined as 0.1 inches or more – has historically arrived in November.
A few of the cities that, on average, see the first accumulating snow of the season in November are Boston (Nov. 29), Chicago (Nov. 16), Cleveland (Nov. 10), Pittsburgh (Nov. 14) and Salt Lake City (Nov. 5).
The date shown for each city is the historical average for the first date of measurable snow. Any given season can produce the season's first snowfall before or after that date, depending on weather patterns.
Month of the average first accumulating (0.1 inches or greater) snowfall of the season, according to 30-year average statistics. In parts of the South, measurable snow is most likely to occur in January or February, but not every year. Version corrected for the Oregon coast on Sept. 30, 2017.

Lake-Effect Snow Ramps Up

The potential for lake-effect snow bands to develop downwind of the Great Lakes increases significantly in November.
Cold air flowing over relatively warm Great Lakes water is the key mechanism for lake-generated precipitation. Although lake-effect snow can occur in October, the chances increase in November given that cold air is generally more abundant the later we get into fall.
Great Lakes snowbelt cities such as Buffalo, New York, and Grand Rapids, Michigan, typically pick up 6 to 8 inches of snow each November. Marquette, in Michigan's Upper Peninsula, gets about two feet of snow in an average November.
The week before Thanksgiving 2014 featured an epic lake-effect snow event in the eastern Great Lakes. Localized snowfall totals of more than 70 inches were measured in the Buffalo Southtowns; an astonishing 88-inch total was reported in Cowlesville, New York.
Cars with snow atop the roofs sit idle at this home on Broadway in Lancaster, New York, Wednesday, Nov. 19, 2014.

November 'Witch' Storms

Some November storms don't make news from wringing out snow.
As temperature contrasts increase from north to south across the country, storm systems that develop are stronger in fall. The more intense those low-pressure systems become, the stronger the winds they can produce.
GOES-16 GeoColor satellite images taken at 8 a.m. EDT, Oct. 23, 2017 (first image), then 24 hours later, showing the bombogenesis of a Great Lakes storm. (Note: City lights overlay is applied in these images.)
Early November – and late October, for that matter – has a long, notorious history of intense Midwest windstorms. If you live in that region of the country, you might have heard of the "Witches of November," used to describe these storms that often pack powerful winds.
Those low-pressure systems can have winds so strong that they cause tree damage and power outages. One such November Witch struck parts of the Midwest and Great Lakes in early November 2015, downing trees and causing power outages.
The storms are a major hazard for shipping on the Great Lakes. One of the most well-known storms sank a huge iron-ore ship called the Edmund Fitzgerald while it was on Lake Superior in November 1975.

Wettest Month in a Notoriously Wet Northwest

November also marks the intensification of the wet season along the West Coast.
For Portland, Oregon, and Seattle, November averages more precipitation than any other month during the year, although December and January aren't far behind.
From November through January, measurable precipitation typically falls 18 days per month in Seattle.
In this Jan. 18, 2017 file photo, pedestrians huddle under umbrellas as they walk past the Pike Place Market and in view of Elliot Bay, behind, in Seattle.
As Pacific storm systems plow inland, they can occasionally tap into a so-called atmospheric river, a narrow plume of moisture extending into the tropics or subtropics.
The atmospheric river provides extra juice for storm systems taking aim at the West Coast. Sometimes, the extra moisture can be overwhelming, with heavy rain causing flooding while feet of snow pile up in higher terrain.
Although these atmospheric river events can bring hazardous impacts, they are also beneficial since they help replenish the water supply in the West.

Severe Weather's Fall Peak

While severe weather can occur any time of year when favorable conditions are in play, November has often been a dangerous month for severe weather outbreaks.
The highest chance of tornadoes in November is near the Gulf Coast.
With jet stream winds becoming stronger in the fall, and lingering warm, moist air available at times, the atmosphere can become unstable. As a result, severe thunderstorms with damaging winds, large hail and occasional tornadoes can develop.
Most of the time, these fall tornado outbreaks occur in the Gulf Coast states, where warm, moist air is more common, but they can sometimes spread farther north.
One such outbreak that occurred far from the Gulf Coast was on Nov. 17, 2013. Damaging tornadoes were spawned in several Ohio Valley and Great Lakes states.
In November 2016, more than three dozen tornadoes hit the South during the final two days of the month. Three of the tornadoes were rated EF3, and two of them killed a combined six people.
The largest fall tornado outbreak struck the South Nov. 21-23, 1992. A total of 105 tornadoes touched down in three days, killing 26 people.
But November isn't all gloom and doom. Let's list some of the positives.

U.S. Hurricane Risk Winds Down

November is the last month of the Atlantic hurricane season, but both the number of named storms and risk to the U.S. is much lower than earlier in the fall.
One named storm typically forms every other November somewhere in the Atlantic Basin.
Only three hurricanes have struck the U.S. in November.
Hurricane Kate made landfall in Florida days before Thanksgiving 1985, marking the latest hurricane landfall in U.S. history.
Hurricane Kate in the Gulf of Mexico.
More recently, Ida in 2009 became the first hurricane since Kate to move into the Gulf of Mexico during the month of November. Ida became a post-tropical storm shortly before reaching the Alabama coast on Nov. 10.
By early Nov. 12, the remnants of Ida had transformed into a powerful non-tropical low-pressure center near the coast of the Carolinas. The Weather Channel dubbed this storm "Nor'Ida," given it's nor'easter-like characteristics.
Nor'Ida then lashed southeastern Virginia and the Outer Banks of North Carolina with coastal flooding, heavy rain and damaging winds as it stalled near the coast.

Florida Begins Its Dry Season

Floridians enjoy the arrival of the state's dry season by November as more northern locations are trending colder.
Dry season setup.
Florida typically dries out by late October, and it stays dry through early spring as cold fronts return to the Sunshine State.
Days could still be warm, but by November, the humidity is lower and temperatures typically cool down at night.
This can make November a delightful time of year to visit. For instance, in Orlando, average high temperatures top out from the mid-70s to low 80s.
Behind these fronts, cooler air near the surface stabilizes the atmosphere, suppressing the almost daily showers and thunderstorms seen in the summer.

Rain in California, At Last

Transplants looking to escape more miserable cold, rain or snow sent California's population skyrocketing in recent decades.
By November, however, some Californians would welcome rain, even if it messes up the daily commute.
The state has a pronounced dry season, with little rainfall from late spring through early fall. By October, vegetation dried out after months of no significant rain serves as fuel for fast-spreading wildfires fanned by Santa Ana and Diablo winds.
California's roughly six-month-long wet season usually ramps up by November, as the jet stream gradually shifts south. This directs Pacific storms not simply into Washington and Oregon, but increasingly into California as well.
California's wet season kicks into gear by November.
As mentioned earlier, some of these West Coast storms with atmospheric rivers can trigger flooding rain, and wildfire-charred land can experience debris flows even in lighter rain.
But overall, this first rain of the wet season can finally provide a break for fatigued fire crews and first responders.
Skiers and snowboarders also love these November storms in the West, as they build up snowpack for those who can't wait to hit the slopes.
The Weather Company’s primary journalistic mission is to report on breaking weather news, the environment and the importance of science to our lives. This story does not necessarily represent the position of our parent company, IBM.

The Weather Company’s primary journalistic mission is to report on breaking weather news, the environment and the importance of science to our lives. This story does not necessarily represent the position of our parent company, IBM.

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