...February 16-17 Winter Storm Summary...


Yet another very strong winter storm system raced through the lower Missouri River Valley this weekend.  This storm produced a combination of heavy rain, ice, sleet, and snow over much of the region.  This storm actually developed much earlier in the week across portions of California, bringing Valentines Day snow to unusually low elevation areas of California and Arizona.  This storm continued to deepen and slowly crawl east, finally reaching the western portions of Texas by Saturday night.  However, as a slightly weaker upper level storm dropped into the United States from the northwest on Saturday, enough of a push was given to dislodge this storm system and quickly race it towards the Great Lakes.  Below you will find both a still image of this storm track as well as a loop of water vapor (or moisture content in the atmosphere) as this storm raced to the northeast this weekend.


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Click on Image for  Larger Animation


Due to the slow moving nature of this storm system, a large volume of moisture was able to advect northward into the Southern and Central Plains priming much of the area for a significant amount of rainfall.  Rain initially developed over Oklahoma, Arkansas, and southern Missouri Saturday morning, quickly streaming northward through the day.  It wasn't until the mid afternoon hours when precipitation blossomed over central and northern Missouri.  Rain, sometimes heavy at times, continued through much of the overnight hours and into early portions of Sunday morning, leaving many locations with rainfall totals in excess of 1.5 inches with widespread rainfall totals between 0.5 and 1.0 inches common.  In addition, portions of extreme northern Missouri also received a glaze of ice as surface temperatures remained slightly below the freezing mark.  This heavy rain when combined with partially frozen and saturated soil created numerous flooding issues.  Particularly hard hit were areas of southern Missouri, where many secondary and main roadways were closed due to rising waters.  Further north, while the heavy rain did cause a few issues with ground flooding, the highest impacts were to rivers in areas south and east of Kansas City.  Many rivers and their tributaries continue to run at high levels, with several rivers going into flooding conditions.  The image below depicts some of the rainfall totals as provided by our cooperative observers and automated equipment.

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However, the impacts from this storm continued to increase as colder air above the ground slowly poured into the region from the northwest.  This colder air, along with a very strong low pressure area at the surface (see animated map below) allowed rainfall to transition to snow over portions of Nebraska, Kansas, and Oklahoma.  This transition to snow rapidly progressed eastward and by daybreak encompassed the entire state of Kansas and much of western Missouri.  Snow was very heavy at times, with accumulation rates of 2.0 in/hr in the city of Topeka and lightning strikes just to the northwest of the city.  In fact, due to the very heavy snow and very wet, slushy nature of the snow, Kansas City International Airport closed for over 5 hours Sunday morning as planes struggled to take off and land.  This was the longest stretch of time that Kansas City International Airport has ever been closed in its current location!!


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Snow continued to fall across the state of Missouri and then further north into Iowa, Illinois, Minnesota, and Wisconsin, with widespread snowfall totals of 3-5 inches in many locations.  Closer to home, the hardest hit locations ranged from near Easton to Amity and Spickard with as much as 6 to 7 inches of snow reported!   However, as temperatures began to warm into the lower to middle 30s, snow quickly started to melt, creating a mess on the roads and reducing the newly fallen snowfall in half.  If you look closely at the animation above, you will also note the very tight surface pressure gradient which caused winds to rapidly increase through the day.  In fact, portions of Nebraska and Iowa received wind gusts in excess of 40 mph, yet another major impact of this winter storm!

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