January deceivingly rates as 50th coolest on record

Certainly 2018 began on a bitterly cold note, highlighted by the second coldest New Year’s Day on record at Indianapolis and the coldest start to a year for the region in 90 years, the National Weather Service office at Indianapolis reports.

Highs struggled to rise into the single digits after starting the year well below zero. Lows the first week were often below zero.

The average temperature for the first six days of the month at Indianapolis was a brutally cold 3.2 degrees, marking the coldest start to a year through the first six days on record.

Warmer temperatures on Jan. 7 ended a 12-day stretch dating back to Dec. 26 in which temperatures failed to rise above 20 degrees, a record period.

Temperatures Jan. 10-11 rose into the upper 50s and largely removed the snowpack that had been built up in late December and the first week of January. Much colder air once again returned in the wake of a winter storm that brought a mixture of wintry precipitation to the area beginning late on the 11th and continuing into the 12th.

High temperatures dropped back below freezing once again from Jan. 13-18, with the coldest air coming on Jan. 16 in the wake of a fresh snow cover as a renewed surge of Arctic air overspread the Ohio Valley.

Beginning Jan. 19, the dominant upper level trough which had enabled repeated shots of bitterly cold air to overspread the eastern U.S. since late December finally relaxed and would not return for the rest of the month. The result was above-normal temperatures through the end of January with highs largely above freezing. Highs flirted with 60 degrees on Jan. 26 as southwest winds brought much warmer air into central Indiana.

Arguably, the best weather day of the entire month came just two days later on the 28th as temperatures rose into the 50s during the afternoon under bright, sunny skies and with little wind.

Indianapolis endured subzero lows on eight nights in January, matching 1994 and 2014 for the most subzero January nights over the last 35 years.

So far, Indianapolis has now had 11 subzero nights in the 2017-18 winter.

In central Indiana, 17 days had above normal-average temperatures and 14 days had below-normal average temperatures as January 2018 was tied for the 50th coolest in the Indianapolis area since weather records began in 1871.

Meanwhile, January 2018 was tied for the 57th driest ever in the Indianapolis area.

Monthly snowfall for January measured from two inches in portions of west-central Indiana to more than 30 inches in LaPorte County in northwest Indiana. Snowfall was below normal for most of central Indiana, normal to above normal in northern Indiana and above normal in southern Indiana.

Much of the snow in northern Indiana was lake effect snow and fell Jan. 1-8. Winter disturbances from Jan. 12-16 brought much of January’s snow to central and southern Indiana. A combination of freezing rain and snow caused significant impacts for much of central Indiana throughout Jan. 12.

A disruptive icy event occurred late on the evening of Jan. 23 into the morning of the 24th as freezing mist and drizzle combined to create a thin layer of black ice on numerous untreated roads with ground temperatures below freezing. Interestingly, precipitation amounts were a trace to a hundredth of an inch

Looking ahead, the official outlook for February 2018 from the Climate Prediction Center indicates a greater chance of below-normal temperatures across much of central Indiana. At Indianapolis, the average temperature for the month is 32.1 degrees.

There is a slightly greater chance for near to above-normal precipitation for central Indiana as well. The average precipitation for February at Indianapolis is 2.32 inches, with 6.5 inches of snowfall.