Intense central US midlatitude cycloneAn unusually deep midlatitude cyclone — which easily met the criteria of a “bomb cyclone”, with its central pressure dropping 25 hPa in only 12 hours (surface analyses) — developed over the central US on 13 March 2019 (WPC storm summary). GOES-16 (GOES-East) Air Mass RGB images from the AOS site (above) showed the large size of the cloud shield — and the deeper red hues over the High Plains indicated the presence of ozone-rich air (from the stratosphere) within the atmospheric column as the tropopause descended. A preliminary new all-time low surface pressure of 975.1 hPa occurred at Pueblo, Colorado just after 13 UTC; to the east of Pueblo, a 970.4 hPa minimum pressure recorded at Lamar (plot) possibly set a new state record for Colorado.
On a map of NWS warnings/advisories valid at 14 UTC (below), Blizzard Warnings (red) extended from Colorado to the US/Canada border. South of the Blizzard Warnings, High Wind Warnings (brown) were in effect to the US/Mexico border.GOES-16 Mid-level Water Vapor (6.9 µm) images (below) displayed a hook-like signature resembling that of a sting jet, which developed over the Texas/Oklahoma Panhandle area after 11 UTC. At 14 UTC an interesting burst of surface wind gusts occurred at 3 sites — Burlington CO, Goodland KS and Colby KS — which may have been related to the downward transfer of momentum along the leading edge of the sting jet flow. The corresponding 7.3 µm Low-level Water Vapor animations are also available: GIF | MP4. The MIMIC Total Precipitable Water product (below) showed the northward surge of moisture from the Gulf of Mexico. During the afternoon hours, the strong surface winds began to create plumes of blowing dust across parts of southeastern New Mexico and western Texas — a blowing dust signature first became apparent on GOES-16 Split Window Difference imagery as plumes of yellow, but then became more obvious on “Red” Visible (0.64 µm) images as the afternoon forward scattering angle increased (below). Blowing dust reduced the surface visibility to 1-2 miles at Snyder (KSNK) and Lubbock (KLBB). The blowing dust signature (lighter shades of brown) was also easily seen in late-afternoon GOES-16 True Color RGB images (below) — the dust plume reached southwestern Oklahoma by the end of the daytime hours, restricting the visibility to 5 miles at Frederick (KFDR). The blowing dust was also evident in True Color imagery from GOES-17, as seen here. Not long after the cyclone reached its lowest analyzed surface pressure of 968 hPa at 18 UTC, an overpass of the Suomi NPP satellite around 19 UTC provided a swath of NUCAPS soundings covering much of the storm (below). The air was very dry and stable near the near the center of the surface low in eastern Colorado (TPW=0.29″, CAPE=0 J/kg), in western Texas (TPW=0.31″, CAPE=0 J/kg) and near the frontal triple point in southeastern Nebraska (TPW=0.30″, CAPE=0 Jkg) — and out ahead of the warm front, the air was moist but stable behind a line of thunderstorms in northeastern Arkansas (TPW=1.09″, CAPE=0 J/kg) but both moist and unstable in western Mississippi (TPW=1.36″, CAPE=3506 J/kg). During the early stages of cyclone development, this system spawned severe thunderstorms that produced tornadoes, large hail and damaging winds across New Mexico and Texas (SPC storm reports) late in the day on 12 March. A GOES-17 (GOES-West) Mesoscale Domain Sector had been positioned over that region — which was helpful during a brief GOES-16 data outage — providing images at 1-minute intervals (below).
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
Powerful low in the Central Plains with widespread significant wind gusts. Over the past 24 hours, NWS offices logged about 350 wind gust reports of 50+ MPH, with a further 92 reports of damage. The most significant gusts (70+ MPH) generally in NE NM, TX Panhandle, E CO. pic.twitter.com/duCPfqdkII
— NWS WPC (@NWSWPC) March 14, 2019
===== 14 March Update =====
Farther to the east, severe thunderstorms produced large hail, damaging winds and tornadoes as far north as northern Illinois/Indiana/Ohio and southern Lower Michigan (SPC storm reports | NWS Detroit) — as shown with 1-minute Mesoscale Domain Sector GOES-16 Visible images (below). The corresponding GOES-16 Infrared image animation is available here; the coldest cloud-top infrared brightness temperatures were only in the -30 to -40ºC range