The NWS Hastings coverage area is located within the orange outlined area labeled "GID", with the Interstate highways in red. (Click Radar Loop To Enlarge)
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Detailed Event Summary:
Leading up to this event, the preceding 8 weeks had been unseasonably warm and dry across most of South Central Nebraska and North Central Kansas, with parts of South Central Nebraska likely drawing ever-closer to receiving a Category D2 (severe) drought designation from the U.S. Drought Monitor. However, this all changed during a roughly 42-hour period centered from Thursday evening, February 2, 2012, through Saturday afternoon, Februay 4th. Within this time frame, much of the 30-county NWS Hastings coverage area experienced its biggest snowfall event of the 2011-2012 winter season so far, with many areas tallying between 6-13 inches of heavy, wet snow. In some areas, lightning occurred within the heaviest snow bands, resulting in “thundersnow.” In addition to (and prior to) the snowfall, several counties mainly east of a Plainville KS-Franklin NE-Grand Island NE line picked up rainfall ranging from 0.25 to over 1 inch. As a result, storm-total precipitation amounts from this system were quite notable for early February, and also quite welcome given the recent dry spell, with the majority of the 30-county area measuring between 1-2 inches. For parts of the area, including Hastings, these liquid-equivalent precipitation amounts were the highest on record for any two-day period during the month of February! (See climate section below for details) Focusing on storm-total snowfall, the heaviest corridor, with amounts averaging at least 7 inches, encompassed about 15 counties and was centered roughly 25 miles either side of a line extending from near Holdrege-Minden-Doniphan-Benedict. This corridor of heaviest snow included the Tri-Cities. As outlined in the tables and maps below, a few of the highest measured snowfall amounts from NWS Cooperative Observers included Bradshaw (13.3 inches), Minden (12.2), York (11.0), Hastings (11.0) and Grand Island (9.4). The combination of this heavy, wet snow, along with north winds gusting to around 30 MPH for several hours, resulted in at least minor tree damage and power outages across the area. Outside the zone of heaviest snow, the far northern, western and southern portions of the NWS Hastings coverage area saw lesser amounts mainly in the 2-6 inch range, including locations such as Ord, Cozad, Elwood, and Hebron, along with all six counties in North Central Kansas. In fact, most of North Central Kansas measured no more than 3 inches. The least snow of all within the NWS Hastings area occurred in Mitchell County KS, where Beloit only had one-half inch, but still totaled 1.68 inches of precipitation mainly in the form of rain. For some of these areas outside the primary snow zone, this was not even the biggest snow event of the winter season so far, with that distinction still belonging to early-season events in December 2011. Looking at the timeline and meteorological background of this event, the culprit was a strong mid-upper level low pressure system that strengthened as it neared the Central Plains. Early in this event, temperatures remained warm enough to support rain as the first round of precipitation lifted across North Central Kansas and mainly eastern portions of South Central Nebraska between Thursday evening, Feb. 2nd, and Friday morning the 3rd. As mentioned above, rainfall amounts from this initial overnight round were commonly between 0.25 to over 1 inch, with some of the highest rainfall totals through sunrise on the 3rd including 1.25 inches at Beloit KS, and 0.97-inch four miles south of Shickley NE. During the daylight hours on Friday the 3rd, the majority of the 30-county area experienced nothing more than off-and-on light rain or drizzle, while the initial band of heavy snow set up across western and north central Nebraska. Finally, as temperatures cooled on the evening of the 3rd, snow gradually increased in coverage and intensity across the NWS Hastings coverage area. The heaviest hourly rates of at least 1 inch per hour, along with pockets of thundersnow, focused between 8 PM on the 3rd and 6 AM on the 4th as the mid-level deformation zone pivoted across the area. During the daytime hours on Saturday the 4th, snow gradually decreased in intensity, with most additional accumulations in excess of 2 inches focused along and east of the Highway 281 corridor.
One of the few areas where snow totals fell noticeably short of forecasted values included western Dawson County. This was largely due to the fact that concentrated snow bands “jumped” over this area, focusing off to the west early in the event, and then re-forming to the east during the evening of the 3rd into the morning of the 4th.
Climate Information: For locations including Grand Island and Hastings, it had been many years since a 2-day precipitation event during the month of February featured so much precipitation and snowfall. In fact, Hastings set an all-time February record for 2-day total precipitation!
Below is a table of Storm Total snowfall, ending Sunday morning, from National Weather Service Cooperative Observers.
Below is a map showing snowfall totals from observations across the area. This snowfall map is a "best-approximation" of actual measured amounts. Some reports may not be included, and amounts reflected on the map may not match locations exactly due to the effects of interpolation and "smoothing" used to create the maps. These preliminary data may contain errors. Click on the image for a larger version.
Below is a table of liquid (melted snow and rain combined) during this event from National Weather Service Cooperative Observers.
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