Extended Streamflow Guidance
Issued by NWS Missouri Basin, Pleasant Hill
Issued by NWS Missouri Basin, Pleasant Hill
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SPRING FLOOD OUTLOOK
NATIONAL WEATHER SERVICE
MISSOURI BASIN RIVER FORECAST CENTER
PLEASANT HILL, MO
MARCH 12, 2025
NARRATIVE PART 1 OF 1
ATTN WFO`S SERVED BY MBRFC.
This Spring Flood Outlook is not for public release until
Thursday, 13 March 2025.
This Spring Outlook is for the Missouri River drainage which
includes rivers in Montana, Wyoming, Colorado, North and South
Dakota, Nebraska, Kansas, Iowa, Minnesota, and Missouri.
SPRING FLOOD OUTLOOK
Overall Flood Risk and Conditions ...
Flood risk this spring within the Missouri River Basin is generally
below normal. While some locations have a near-normal flood risk
and one or two river locations have an increased flood risk, the
overall basin-wide risk remains lower than historical flood risk.
To provide context:
- A normal flood risk means that locations that typically
experience springtime flooding are likely to flood again this
year. However, this does not guarantee that flooding will occur.
- For locations that do not typically flood, a normal risk
indicates that flooding is again not expected.
- A reduced flood risk does not necessarily mean flooding will
not occur, nor does an increased flood risk guarantee that
flooding will happen.
In spring 2024, the Missouri River Basin made substantial progress
toward recovering from a three-year drought. Following above-normal
precipitation, the June 11, 2024, U.S. Drought Monitor categorized
less than 10% of the basin in droughtthe lowest percentage since
June 2020.
However, since June 2024, soil moisture conditions have steadily
declined, and today, 62% of the basin is classified in some level
of drought. This indicates that, for all practical purposes, the
basin is now in its fifth consecutive year of drought.
Recent Flooding ...
Unseasonably warm temperatures beginning mid-February resulted in
the loss of one to two inches of snow water equivalent from lower
elevations across eastern Montana. This rapid runoff, coupled with
the presence of river ice, led to significant rises along
many eastern Montana rivers. Several reports of flooding in
low-lying areas were reported.
Meanwhile, in the lower one-third of the basin (eastern Kansas and
Missouri), spring flooding is typically driven by thunderstorm
activity. Around February 1, several lower basin tributaries
exceeded flood stage following a couple inches of rain on soils
moistened by January snowmelt. Additionally, snows and gradual melt
throughout February kept soils moist prior to an early March
rainfall event which yielded flooding again for the lower basin
tributaries.
Mountains & Plains Snowpack (and Frost Depths) ...
Over the past couple of weeks, the Missouri River Basin has
continually lost most of its widespread but shallow Plains snowpack,
even with successive snow storms. At this time, any Plains
snowpack, past or future, is not expected to enhance flood risk.
However, in the absence of an insulating snowpack, soils have been
allowed to develop a fairly deep frost depth in some areas,
especially across the Dakotas.
Over the past couple of weeks, the top layers of soil have begun
to thaw in areas where frost depths were deep. Soils, while cold in
the northern plains, are also extremely dry, and therefore there is
the presumption that northern soils may still be able to accept
some runoff when plains snow melts, or when Spring rains fall.
In the mountainous west, snowpack is near average. We are
approximately 80% of the way through the normal peak snow water
equivalent accumulating period for the mountain snow, so there is
still time for conditions to change.
Water Supply ...
Water supply forecasts issued in early March by the National
Weather Service project lower than average April-September runoff
volumes for all of the mountainous west. Most locations are
expected to receive 50-75% of normal mountain runoff this year.
More information regarding current Water Supply Forecasts can be
accessed at: https://weather.gov/mbrfc/water
Ice Jam Flooding ...
River ice action has posed some problems already this winter. One
notable case being the series of ice jams which formed along the
lower Missouri River north of Omaha, Nebraska due to anomalously
cold early January temperatures. These ice jams did not raise
flooding concerns, but rather resulted in a precipitous drop in
river stage creating low flows though the system. Another ice jam
formed north of Omaha again in early February, but with less
impacts than the January event.
Weve also had ice jam flooding along the Madison,
Jefferson, and Tongue Rivers in the plains of Montana due to
unseasonably warm temperatures in late February. This resulted in
the melting of 1 to 2 inches of snow water equivalent from
lower-elevation areas. The runoff, combined with river ice, caused
rivers to rise significantly in eastern Montana. Additional ice jam
flooding has occurred along the Loup and North Platte Rivers in
Nebraska and the Shoshone River in Wyoming.
While ice jam break-up flooding risk is considered low this year,
wherever river ice remains, so does the risk for ice jam flooding.
Please note, the probabilistic quantifications that form the
basis for this Spring Flood Outlook do not take into account the
presence of river ice.
Flood Potential ...
Springtime flooding in the lower one-third of the basin, including
eastern Kansas and the state of Missouri, is typically driven by
thunderstorm activity. Flooding is projected to occur again this
spring in this region of the basin. As mentioned above, we have
already experienced flooding in this area as recently as early
March, where several locations along the Kansas-Missouri border.
The following state by state flood potential discussions are based
on long-range probabilistic river outlooks developed this week.
Again, it must be stressed, these outlooks do not take into account
the presence of river ice.
Kansas:
- Moderate flooding is expected on Stranger Creek and Little
Osage River.
- Minor flooding is projected for the Big Blue, Black Vermillion,
and Marais des Cygnes Rivers.
Missouri:
- Moderate flooding is expected on the Grand, Crooked, and
Blackwater Rivers, as well as Big Creek.
- Minor flooding is expected on the Missouri River, Chariton
River, Hinkson Creek, Tarkio and Platte Rivers, Petite Saline,
Moreau and Wakenda Creeks as well as Big Piney River, Little
Osage, Marmaton, Sac, and South Grand Rivers.
These projections of river stages are based on current observed
states of streamflow, soil moisture, and snowpack, coupled with
future precipitation and temperature patterns and anticipated
operational hydrologic changes such as reservoir releases and canal
diversions. "Outlooks" are provided for long-range (weeks to
months) projections based on climatological patterns of
precipitation and temperature. "Forecasts" are provided for
short-term (days) projections based on forecast patterns of
precipitation and temperature. The uncertainty of these products
varies from season to season and location to location. The
uncertainty of forecasts tend be less than the uncertainty of
outlooks due to their shorter lead time.
Users of these products are encouraged to contact their nearest
National Weather Service Forecast Office for continued updates of
meteorological conditions which can have significant impacts on
flood preparedness planning and flood fighting activities.
For additional quantitative information please refer to NWPS
products for probabilistic outlooks of potential flooding. Refer
to short-term flood forecasts and products, if any are currently
issued, for information about ongoing or near-term anticipated
flooding.
This is the last scheduled Spring Outlook of the 2025 season.
Should significant changes occur subsequent to this Outlook,
additional Outlooks can be released to update expected conditions.
Additional river information, including the monthly Water Supply
Outlook, can be accessed at the following URL:
https://weather.gov/mbrfc
Current Snow Conditions
The conditions listed below are based on observations and model
data as of Wednesday morning, March 12th.
Montana, Wyoming, and Colorado Plains
Little to no snow is being reported across the plains of Montana,
Wyoming, and Colorado.
Mountainous West
Snowpack conditions in the mountainous areas of the basin are
generally near to below normal. In Montana, the Jefferson,
Musselshell, Missouri headwaters, Sun, Teton, and Marais River
basins are reporting a below to near normal snowpack (70-100%). The
St. Mary and Milk basins are reporting a near to below normal snowpack
(70-100%). In Wyoming, the Tongue, Bighorn, Powder, Wind, and
Yellowstone River basins are reporting a near to below normal
snowpack (85-100%). The higher elevations of the North Platte
River basin are reporting a near normal snowpack (99%). In
Colorado, the higher elevations of the South Platte River basin
are reporting a near normal snowpack (103%).
North Dakota
Snow depths across northwestern North Dakota are generally less
than 1.0 inch, with water equivalents less than 0.5 inches.
Elsewhere across North Dakota, little or no snow is being reported.
South Dakota
The Black Hills in South Dakota are reporting 10-15 inches of snow depth
with water equivalents in the 1-4 inch range. Elsewhere across
South Dakota, little or no snow is being reported.
Iowa, Nebraska, Missouri, and Kansas
No snow is being reported across Iowa, Nebraska, Missouri, and Kansas.
Current Soil Moisture Conditions
The US Drought Monitor indicates that portions of the Missouri
River basin are experiencing below normal soil moisture
conditions. Extreme drought is indicated across portions of
western North Dakota, northern and southeastern Wyoming, northwestern
Nebraska, and southwestern South Dakota. Moderate to severe drought
is indicated across eastern Montana, southern North Dakota, much
of South Dakota, Wyoming, and Nebraska, northern Kansas, western
Iowa, and southwestern Missouri.
Isolated frost depth reports suggest that soils across Montana,
Wyoming, South Dakota, and North Dakota have frost penetration
ranging from 0.5-4 feet. Frost depths of less than 0.5 feet
are being reported across Colorado, Kansas, Nebraska, Iowa,
and Missouri.
Current River Conditions
Generally, river levels across the basin are currently running near
to below normal, or estimated to be so if the rivers are frozen.
A summary of river flow conditions at selected river stations for
March 12th follows:
Long Term Current
Mean (CFS) (CFS)
James River - Huron, SD 292 146 (EST)
Big Sioux River - Akron, IA 1980 390 (EST)
Platte River - Louisville, NE 11800 5280
Kansas River - Desoto, KS 6020 1630
Gasconade River - Jerome, MO 5070 1790
Missouri River - Omaha, NE 24600 19000
Missouri River - Rulo, NE 38500 25500
Missouri River - St. Joseph, MO 42400 27800
Missouri River - Waverly, MO 50100 34700
Missouri River - Hermann, MO 90500 59200
END MBRFC
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