An intense March storm is challenging all-time low barometric pressure records and has begun to unload heavy snow and blizzard conditions in the central U.S. The National Weather Service’s Weather Prediction Center has called this storm a ‘cyclone of historic proportions.’
A Great Plains cyclone of historic proportions is now underway across the central U.S. Here’s the latest… pic.twitter.com/CLAsDmmOkZ
— NWS WPC (@NWSWPC) March 13, 2019
As of Wednesday midday, blizzard conditions have begun to spread from north-central Colorado to much of southeastern Wyoming, the northwestern corner of Nebraska and part of western South Dakota.
“We expect a major blizzard with winds likely to approach hurricane force, heavy snow and massive drifts,” according to AccuWeather Senior Meteorologist Alex Sosnowski.
“The uneven weight of the snow, due to drifting, may cause some flat roofs to fail,” Sosnowski said.
With atmospheric pressure crashing more than the 0.71 of an inch threshold in 24 hours the storm underwent bombogenesis.
According to preliminary National Weather Service (NWS) data, Colorado and New Mexico broke their all-time low barometric pressure records on Wednesday.
View of Plain’s #BombCylone from 3 PERSPECTIVES. Visible, Enhanced Infrared and Water Vapor. Barometric pressure (yellow lines) showing a 974 mb low at peak. This is the LOWEST “SLP” recorded to date in Colorado. WOW! #COwx #goes16 #USwx More from NOAA: https://t.co/zlzGtubuAR pic.twitter.com/VnEnAQ1IH8
— Jeremy Kappell (@JeremyKappell) March 13, 2019
The old records stood at 28.82 inches of Mercury (975.8 millibars) in La Junta, Colorado, in 1973, and 28.90 inches of Mercury (978.7 millibars) in Clayton, New Mexico. However, pressure records are not routinely maintained in all states and it may take some time until these levels are verified.
Using WPC’s record low pressure map, it looks like records have been set for the states of Colorado and New Mexico this morning, although state climatologists say “state record” and “pressure record” are both tough to define, so that may not be confirmed. pic.twitter.com/pDA0wOMqZI
— Jesse Ferrell (AccuWeather) (@WeatherMatrix) March 13, 2019
Kansas could see its all-time record-low barometric pressure set as the center of the storm tracks over the state. The current state record is 28.68 inches of Mercury (971.2 millibars) set at Dodge City in 1878. If the barometric pressure plummets to a record low, this will be the most intense storm to track across Kansas in state history.
…RECORD LOW PRESSURE POSSIBLE WEDNESDAY…
All-time record low pressure at Dodge City is 971.6 mb, set in 1878.
Modern-time record at Dodge City is 974.9 mb, set in 1960.
Several models are showing sea-level pressure as low as 972-974 mb Wed. afternoon. #kswx
— NWS Dodge City (@NWSDodgeCity) March 12, 2019
The snowstorm is forecast to travel northeastward to the northern Plains Wednesday night into Thursday.
The swath of heavy snow will fall from northern Colorado, including Denver, to western Nebraska, southeastern Wyoming, central South Dakota and southeastern North Dakota.
A portion of this corridor can receive 12-18 inches of snow with an AccuWeather Local StormMax™ of 26 inches.
In addition to Denver, other cities in the current path of the heaviest swath of snow include Cheyenne, Wyoming; Sidney, Nebraska; Pierre, South Dakota; and Fargo, North Dakota.
AccuWeather meteorologists will continue to monitor the exact track of the storm as any shift could cause the burying snow band to set up west or east of these cities.
“On top of the heavy snow, strong winds will lead to blizzard conditions with very low visibility and snow-packed roads,” according to AccuWeather Meteorologist Steve Travis.
Major disruptions to travel and daily routines await those in the path of this blizzard.
Travel can become extremely difficult to impossible along interstates 25, 29, 70, 76, 80 and 90. Officials may be forced to close stretches of these interstates and other highways.
“Anyone with plans to travel across these areas midweek will want to plan ahead for this disruptive storm,” added Travis.
Denver International Airport may be forced to close at the height of the storm with disruptions likely to persist in the days after the storm as crews work to clear runways, de-ice planes and get flights back on schedule. More than 1,000 flights have been cancelled at the airport. People should confirm their flight before venturing out in the conditions.
The ripple effect of disruptions at Denver can impact travelers elsewhere in the nation.
Schools not on spring break may be forced to close for one or more days.
Residents may also face power outages due to the strong winds, in addition to severe blowing and drifting snow. The greatest risk zone for regional to widespread power outages with the blizzard may lie from eastern Colorado to central South Dakota.
SNOW OR RAIN
The snow can also be heavy and wet in nature where it starts as rain, making shoveling difficult in the storm’s aftermath. The elderly and anyone with heart-issues should seek assistance in clearing sidewalks and driveways.
On the warmer side of the storm, heavy rain will trigger short-term flooding across a large swath of the Plains from Texas to southern Minnesota.
The storm may also set into motion long-term flooding for the North Central states.
Omaha, Nebraska; Sioux Falls, South Dakota; and Minneapolis are expected to be in the path of the storm’s soaking rain.
The rain may end as a little snow in all of these cities. Even if there is not a significant accumulation, any lingering wet areas can freeze on Thursday night as fresh cold air plunges in behind the storm.
Last night there were tornadoes in New Mexico and 150,000 people in Texas lost power after a line of storms came through.
Always be prepared!