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A Mild, Tranquil Election Day on Tap

By: Bob Henson 5:22 PM GMT on November 07, 2016

The weather will be doing its part to keep the mood positive when Americans go to the polls on U.S. Election Day, Tuesday, November 8. Temperatures should be near or above normal over nearly all of the contiguous 48 U.S. states, continuing a string of mildness that’s lasted for weeks in many locations. Freezing temperatures will be largely absent on Tuesday morning outside of the higher terrain of the Rockies and New England (plus most of Alaska, of course). Afternoon readings from the 40s to 60s Fahrenheit will prevail over most of the nation, quite reasonable for early November. The only precipitation of note will be some mostly light rains ahead of a fairly weak upper-level trough extending from Michigan to the Gulf Coast.

It doesn’t look like Tuesday’s weather will have a major impact on the national-level outcome. However, there are cases where inclement weather may have actually swung U.S. presidential races, according to a WU news article by freelance contributor Sami Grover. The rapid spread of early voting in many U.S. states is likely blunting the effect of weather on Election Day turnout, noted Grover.

Figure 1. Precipitation forecast for the six hours from 7:00 am to 1:00 pm EST Tuesday, November 8, 2016, as projected by the 12Z Monday run of the GFS model. Image credit: tropicaltidbits.com.

Warmth by the numbers
As detailed by weather.com, a number of Midwestern locations could experience their latest first freeze of any year on record this year, including Minneapolis (Nov. 7), Des Moines (Nov. 13), and Detroit (Nov. 15). Here’s another telling illustration of how consistently mild the nation has been over the past several weeks: The preliminary total of U.S. daily record highs either tied or broken for the one-week period ending on November 4 was 887, while the corresponding number of daily record lows was a mere 1. Referring to the 887-to-1 ratio, independent meteorologist Guy Walton said: “Since cataloging record counts starting on 1/1/2000, this is the highest weekly ratio of daily highs to daily lows I have ever seen!” The numbers were almost as lopsided for the week ending November 7 (see Figure 2). Preliminary numbers typically grow a bit larger as late-reporting stations come in.

Figure 2. Preliminary data on U.S. records for the week ending November 7, 2016. The month to date has seen 1324 daily record highs set or tied, but only 7 daily record lows set or tied. Image credit: NOAA/NCEI.

As we discussed in a post last week, the biggest story of U.S. temperatures in 2016 is not the large number of daily record highs but the phenomenally small number of daily record lows--less than half as many as for any year on record since the 1920s, when enough data had accumulated to make such comparisons.

The absurdly consistent warmth has been especially evident across the South. As noted by weather.com’s Jonathan Erdman (@wxjerdman), a remarkable eight-day string of consecutive daily record highs began in Meridian, Mississippi, on October 28 and ended on November 4. The streak included a new all-time November high of 89°F on the 1st. Records in Meridian began in 1889. At the opposite end of the United States--Alaska--you’ll also find incredible mildness (relatively speaking). Readings on the Arctic Ocean coast at Barrow have been above average every day since September 15. The typical high and low in Barrow on November 7 are 9°F and -2°F, but as of Monday morning, Barrow had yet to dip below 13°F this entire autumn. We’ll have more on this fall’s amazing Arctic mildness later in the week.

Nationwide, at least 272 U.S. stations set or tied all-time monthly highs for November during the first seven days of the month. That’s a large chunk of the 860 monthly highs set or tied during the entire year up to November 7.

Will autumn arrive before winter?
Over the last several days, long-range computer model guidance has become increasingly insistent that a switch to much chillier weather could occur over the bulk of North America in about 10 to 15 days, perhaps kicked off with a very blustery Midwestern storm. This is at the outer edge of confidence in major pattern shifts, so we’ll have to see if the apparent trend holds water over the next few days. I wouldn’t hold my breath waiting for widespread record lows, but at this point even a shift toward near-normal temperatures would feel bracing.

Two killed as large tornado strikes near Rome, Italy
A massive, highly visible tornado injured dozens of people and startled many more in central Italy on Sunday evening (see embedded photo below). The twister struck around 6 pm local time near the coastal town of Ladispoli, about 20 miles west of central Rome and only about 10 miles northwest of the city’s international airport. Weather.com reported that one man was killed in Ladispoli by a cornice falling from a building, while another in Cesano, about 10 miles northeast of Ladispoli, was crushed by a falling tree. Dramatic video of the tornado can be found on the Facebook page Severe Weather Europe. Weaker tornadoes were reported on Sunday on the Canary Islands and the island of Sardinia.

Figure 3. Severe weather outlook for Monday, November 7, 2016. Image credit: European Storm Forecast Experiment (ESTOFEX).

The ESTOFEX project (European Storm Forecast Experiment) warned that more severe weather was possible Monday afternoon and evening across southern Italy east to Albania ahead of a strong, slow-moving upper-level trough. Ahead of the trough, jet-stream level winds of more than 100 mph were juxtaposed above relatively warm, moist air over the Tyrrhenian Sea. ESTOFEX noted the presence of very strong vertical wind shear resulting in storm-relative helicity (rotation) values of 400 to 1000 m2/s2, “which favors strong mesocyclones that can easily produce a (violent) tornado as well as large hail.” The juxtaposition of moist air from the Mediterranean and dry air from Africa is also a key factor in producing severe weather over the region, according to The Weather Guys (CIMMS/SSEC/University of Wisconsin-Madison). “Because these circumstances are most likely to get organized in the late fall, the limited tornado season that does occur in Italy occurs in October and November,” they write. “It would be interesting to know how many merchant vessels in the long history of Venice have gone down in such autumn storms.”

Tornadoes and other localized forms of wild weather are the focus of the American Meteorological Society’s 28th biennial Conference on Severe Local Storms, which kicked off Monday in Portland, OR. You can follow news from the meeting at the Twitter hashtags #SLS2016 and #SLS16. The agenda is online, with links to abstracts.

We’ll be back with a new post by Tuesday afternoon.

Bob Henson

From the windy top of the Grandfather Mountain
From the windy top of the Grandfather Mountain
Rainy Autumn Ride
Rainy Autumn Ride

Heat Tornado

The views of the author are his/her own and do not necessarily represent the position of The Weather Company or its parent, IBM.