SPRING FLOOD OUTLOOK
NATIONAL WEATHER SERVICE
MISSOURI BASIN RIVER FORECAST CENTER
PLEASANT HILL, MO
MARCH 13, 2024
NARRATIVE PART 1 OF 1
ATTN WFO'S SERVED BY MBRFC.
This Spring Flood Outlook is not for public release until Thursday,
14 March 2024.
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
Flood risk this Spring within the Missouri River basin continues to
vary from near-normal to below-normal. No areas have an above-normal
risk for flooding this Spring.
To provide context, a normal risk indicates that a location that
typically experiences Spring time flooding is likely to see
flooding again this year. However, a normal risk for flooding does
not necessarily mean that a location is expected to flood. For those
locations which do not typically experience flooding, a normal risk
simply indicates that flooding is again not expected this year. By
the same token, a reduced risk of flooding does not necessarily
mean that flooding is not expected. On the other hand, an
increased risk does not necessarily indicate flooding is likely.
While soil moisture conditions have improved over the past year,
the US Drought Monitor valid 05 March 2024 still shows 65% of the
Missouri River basin as being abnormally dry. This drier than
normal soil moisture condition plays a key role in the reduced flood
risk found in many areas of the basin.
Mountain snowpack is well below average in the Milk, upper Missouri,
and Yellowstone River basins. The headwaters of the Platte River
system are faring much better, with a near-average snowpack.
Flooding in the mountainous areas due to snowmelt alone is not
likely this year.
Water supply forecasts issued in early March by the National
Weather Service project lower than average April-September runoff
volumes for most of the mountainous west. More information regarding
current Water Supply Forecasts can be accessed at
weather.gov/mbrfc/water
There is almost a complete absence of plains snow in the Missouri
River basin at this time. While the absence of plains snow figures
into the reduction of Spring flood risk, it has allowed a decent
frost depth to develop in some areas. Frozen ground could play a
significant role in enhancing runoff across portions of North Dakota
and Montana.
With the warmer-than-normal temperatures experienced across the basin
over the past couple of months, river ice along many of the rivers in
the northern plains is either rotting in place, or has moved out
altogether. Although the risk for future ice jam break-up flooding
is now considered low, 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.
Springtime flooding in the lower one-third of the basin, including
eastern Kansas and the state of Missouri, is driven by the
thunderstorm activity typically seen in this area this time of year.
Late last week, one tributary located in southern Missouri
experienced minor flooding due to receiving about an inch of rain.
And so it comes as no surprise that the NWS is projecting continued,
on-again, off-again, episodic flooding in the lower basin as we close
out the Spring and enter into early Summer.
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.
In Kansas, Stranger Creek is expected to have moderate level
flooding, while the Little Osage, Big Blue, and Marias des Cygnes
Rivers are projected to have minor flooding.
In the state of Missouri, the Grand, Crooked, and Blackwater Rivers
are outlooked to experience moderate flooding, as do Hinkson and Big
Creeks. The Chariton, Tarkio, Platte, Little Blue, Lamine, Moreau,
Big Piney, Little Osage, Marmaton, and Sac Rivers are projected to
see minor flooding, as does Wakenda, Moniteau and Petite Saline
Creeks. The Missouri River downstream of Kansas City to the mouth
is also likely to experience minor flooding between now and mid-June.
Looking just beyond the 90-day typical outlook window, minor
flooding is possible along the Nebraska City through Atchison reach
of the lower Missouri River.
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 AHPS 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 2024 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:
http://weather.gov/mbrfc
Current Snow Conditions
The conditions listed below are based on observations and model
data as of Wednesday morning, March 13th.
Montana, Wyoming, and Colorado Plains
Snow depths are generally less than 2 inches with water
equivalents less than 0.5 inches across the plains of Montana,
Wyoming, and Colorado.
Mountainous West
Snowpack conditions in the mountainous areas of the basin (as of
12z on March 13th) are generally below normal. In Montana, the
Jefferson, Musselshell, Missouri headwaters, Sun, Teton, and Marais
River basins are reporting a below normal snowpack (60-80%).
The St. Mary and Milk basins are reporting a below normal
snowpack (65-75%). In Wyoming, the Tongue, Bighorn, Powder,
Wind, and Yellowstone River basins are reporting a below normal
snowpack (60-90%). The higher elevations of the North
Platte River basin are reporting a below to near normal
snowpack (80-100%). In Colorado, the higher elevations of the
South Platte River basin are reporting a near normal
snowpack (90-100%). An incoming major winter storm could dump
1 to 3 feet of snow over the high elevations of Colorado and
Wyoming beginning tonight.
North Dakota
No snow is being reported across the state of North Dakota.
South Dakota
The Black Hills in South Dakota have 10-16 inches of snow depth
with water equivalents in the 1-3 inch range. Less than one inch
of snow depth is being reported across the remainder of the state.
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.
Moderate to severe drought is indicated across portions of Montana,
northern Wyoming, northern Kansas, southeastern Nebraska, and western
Iowa. Abnormally dry to moderate drought is indicated across southern
Wyoming, North Dakota, South Dakota, and Missouri.
Isolated frost depth reports suggest that soils across Montana,
Wyoming, northern South Dakota, and North Dakota have frost penetration
ranging from 0.5-3 feet. Frost depths of less than 0.5 feet are
being reported across southern South Dakota, Colorado, Kansas, Nebraska,
Iowa, and Missouri.
Current River Conditions
Generally, river levels across the basin are currently running
below normal, or estimated to be so if the rivers are
frozen. The exception is across southwestern Missouri where
rivers are flowing near to slightly above normal due to recent
rain.
A summary of river flow conditions at selected river stations for
March 13th follows:
Long Term Current
Mean (CFS) (CFS)
James River - Huron, SD 411 548
Big Sioux River - Akron, IA 2250 440
Platte River - Louisville, NE 10000 6280
Kansas River - Desoto, KS 3460 1140
Gasconade River - Jerome, MO 2750 2900
Missouri River - Omaha, NE 22400 16100
Missouri River - Rulo, NE 37500 21900
Missouri River - St. Joseph, MO 40000 24300
Missouri River - Waverly, MO 46500 26100
Missouri River - Hermann, MO 72700 39700
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