The New Year's Monster Snowstorm of 1999
The northern hemispheric longwave pattern began the year in transition as a high zonal index hinted at major changes to the longwave pattern over the New Year's Day weekend. Forecasters saw the potential for a major storm and issued a Winter Storm Outlook on December 31st. Two potent shortwaves...one associated with the northern branch of the jet stream and the other associated with the southern branch...were progged to phase together over the central plains on the 2nd of January as Winter Storm Watches were hoisted across much of the midwest. Lee troughing developed during the day on the 1st with the eventual surface low developing across the Texas panhandle that afternoon. Forecasters were quick to issue Winter Storm Warnings as tremendous moisture was advected off the Gulf of Mexico during the afternoon of the 1st as the low deepened. Severe thunderstorms erupted along the advancing cold front through the deep south while moderate to heavy snow broke out across the midwest.
On the 2nd of January...intense low pressure was located over northeast Arkansas and slowly moved north-northeast into northwest Indiana by late evening. Snowfall rates of 1 to 2 inches per hour were common throughout the day with even heavier snow noted as the surface/mid and upper level systems wrapped up and became closed off over northern Illinois that evening. Nearly all the snowfall across northern Indiana...southern Michigan and northwest Ohio was due to the tremendous warm advection that occured on the nose of a 75 knot low level jet overtop the shallow cold dome that was in place. Precipitation in areas along and east of a Lafayette Indiana to Defiance Ohio line eventually changed over to freezing rain and sleet as 850 millibar temperatures warmed to above freezing. Snowfall amounts were the highest observed since the Blizzard of 1978 in many areas. Several cooperative observer stations reported all-time record 24 hour snowfalls as well. Storm snowfall totals ranged from in 18-24+ across northwest Indiana and southwest Michigan...12 to 18 across north central Indiana into south central Michigan and extreme northwest Ohio...and 6 to 8 inches from central Indiana into western Ohio, where significant sleet and freezing rain later fell on top of the heavy snow.
Impacts on the people across the area were significant. Most rural roads remained impassable for several days. Schools and some business were closed for up to two weeks after the snowstorm. Many buildings...especially manufacturing warehouses and large retail stores in the areas that received the heavier snow...reported collapsed roofs due to the enormous weight of the snow. A truely remarkable snowstorm and one for the history books.
This story written and compiled by Todd Holsten