Floodwater in Farwell in 2024, (Brian Neben, Central Nebraska Today)
HASTINGS — This outlook is for the Hastings Hydrologic Service Area (HSA). In central and south-central Nebraska this outlook includes the Platte, Loup, Little Blue and Republican Rivers and their tributaries. In north central Kansas, the Solomon River and its tributaries are included.
The window for potential early-spring flooding from ice jams is still present primarily along the Loup and Platte Rivers. This window for possible ice jam flooding is quickly closing but will continue through around Friday, Feb. 28 to Saturday March 1 when after that point we expect most ice will have cleared out and moved downstream of our forecast area.
The longer-term potential for spring flooding (not related to ice jams/snow melt) is currently considered below normal across our area.
Shorter Term Hydrologic Outlook – Feb. 27- March 13
The primary flooding concern in the short term will be the possibility for ice jam induced flooding as the river ice melts and breaks up through Friday February 28th or possibly into Saturday March 1. After March 1 any appreciable river ice is expected to have either melted or moved downstream.
Our hydrologic service area is expected to remain mostly dry until a possible storm system brings a chance for rain and snow by around Tuesday March 4. Although some frost remains in the ground as of Thursday Feb. 27, this frost is expected to have melted by our next rainfall and thus we expect good infiltration when the rain comes due to the dry soil. Therefore, flooding due to rainfall is not expected over the next two weeks.
Longer Term Hydrologic Outlook – March 13 Through May 30
The overall potential for broader-scale spring flooding is below normal across our 30-county forecast area.
Spring flood outlooks are routinely issued from February into March to give advanced notice of any signals that might favor an increased risk of mainly broader-scale flooding (beyond localized ice jam issues). These outlooks incorporate various factors including, soil moisture, snowpack magnitude, stream flow conditions, and the longer-range forecast of future precipitation.
There are several primary factors leading to our below average threat for spring flooding.
– The local snowpack has already melted.
– The mountain snowpack in the Platte River Basin is near to below normal.
– Lake McConaughy (upstream of our forecast area along the North Platte River) is at only 58 percent capacity and has plenty of storage space available.
– Soil moisture is drier than normal across our area (as evidenced by most of our area being in Moderate Drought/D1). As a result, our soils will be capable of efficiently absorbing most normally occurring spring rainfall.
– Current streamflow on our primary river systems is mainly near normal to below normal for this time of year, especially along the Platte basin southward into northern Kansas. However, parts of our Loup River system are indicated to have slightly above normal flow.
– The latest Climate Prediction Center (CPC) three-month precipitation outlook for March-May favors a slight lean towards below normal precipitation.
It is important to note that isolated/localized spring flooding is always possible from occasional bouts of heavy rain/thunderstorms, even in dry years, when the overall, larger-scale risk for
widespread flooding is considered low.
Current and Recent Hydrologic and Climatological Conditions
For an overview of annual precipitation totals/departures from normal along with drought conditions/trends across our 30-county forecast area during calendar-year 2024, please check out our web story at: https://www.weather.gov/gid/2024precip_recap
Turning to current drought conditions and recent trends (per weekly updates by the U.S. Drought Monitor/USDM), and despite the prevailing dryness, drought categories have actually
remained largely unchanged across our 30-county area so far this winter. This is due to a combination of coming into the winter months right on the heels of a notably wet November, along with the fact that winter is the climatologically driest time of the year.
As of the Feb. 4 USDM issuance, around 84% of our area was under Moderate Drought (D1), with only small slivers of Dawson, Valley, and Sherman counties assigned Severe Drought (D2). Meanwhile, the remaining 14% of our area was assigned less-serious Abnormally Dry (D0), mainly centered over some Nebraska counties west of Highway 281 and along/south of Interstate 80.
.Climatological Outlook
Meteorological Spring (March-May):
Turning to the upcoming meteorological spring months of March-April-May as a whole, the latest Climate Prediction Center (CPC) three- month outlook (issued Feb. 20) indicates “equal chances” across our area for temperatures to average above normal, below normal, or near normal.
Precipitation in/near our forecast area is primarily a slight lean toward below normal precipitation being the most likely outcome. Based on 30-year normals, total March-May precipitation across the NWS Hastings coverage area typically ranges from 7-10 inches, with the lowest amounts generally west of Highway 183 and highest amounts near the Highway 81 corridor.
U.S. Seasonal Drought Outlook (issued by CPC on Feb. 20th and valid through May 31): Going hand in hand with the slight lean toward below normal precipitation this spring, this outlook indicates that drought of at least Moderate (D1) intensity is likely to persist across most of our area.
(The longer-range forecasts issued by CPC and referenced in the preceding paragraphs are based on output from various forecast models, as well as forecaster expertise, and take into consideration
ongoing global/tropical atmospheric and oceanic states, recent trends in observed data, soil moisture conditions, etc. More information about these longer-range forecasts can be obtained from the CPC web site at: https://www.cpc.ncep.noaa.gov)
