Flood Potential Outlook Issued by NWS Duluth, MN
000
FGUS73 KDLH 141603
ESFDLH
MNC001-017-021-031-035-061-071-075-115-137-WIC003-007-013-031-
051-099-113-129-281700-
PROBABILISTIC HYDROLOGIC OUTLOOK
NATIONAL WEATHER SERVICE Duluth MN
1100 AM CDT Thu Mar 14 2024
...Spring Flood and Water Resources Outlook...
This outlook covers NE Minnesota and NW Wisconsin for river forecast
points on the headwaters of the Mississippi, Chippewa, St. Croix,
and Rainy Rivers.
...Changes Since Previous Issuance February 29th...
Precipitation over the past two weeks across the region was generally
0.5 to 1 inches below normal. Temperatures were well above normal.
Dry conditions have pushed chances for spring flooding lower than the
previous issuance.
...Current Conditions...
Precipitation since October has been near normal across the region
except north central Wisconsin and Lake and Cook counties where it
has been below normal. Much of the precipitation fell as rain and
runoff was observed over the last week of December. No frost was
present after the late December rains thus in addition to the
rainfall runoff some rainfall percolated into the soil which soon re-
froze.
A widening area of moderate drought conditions continue expanding
across the entire area. Severe drought exists in northern Wisconsin.
If dry conditions continue further drought development is likely.
The lack of snowpack is the main driver of the spring river
forecasts. Record low snowpack is occurring across NE Minnesota and
NW Wisconsin. Without an insulating snowpack the frost has
reestablished to a depth of 22 inches. Frost depth is important
because any heavy rainfall on frozen ground could generate
efficient and rapid runoff. Rain on frozen ground is not well
accounted for in the model solutions below.
Rivers in the area are mainly ice free due to the recent warm weather
and are displaying normal to below normal flow. However without well
above normal precipitation river levels will remain steady or
decrease then fall below normal as we will not see rise from
snowmelt.
...Climate Outlook...
Looking ahead at precipitation chances we see a signal for above
normal precipitation for the period March 21 to 27. Temperature
outlooks for the next two weeks indicate below normal temperatures.
The Climate Prediction Center will publish the April outlook on March
25th.
...Below Normal Chances of Spring Flooding Across the Area...
In Table 1 below...the current (CS) and historical (HS) or normal
probabilities of exceeding minor...moderate...and major flood stages
are listed for the valid time period.
CS values indicate the probability of reaching a flood category
based on current conditions.
HS values indicate the probability of reaching a flood category
based on historical or normal conditions.
When the value of CS is more than HS...the probability of
exceeding that level is higher than normal. When the value of CS is
less than HS...the probability of exceeding that level is lower
than normal.
...Table 1--Probabilities for minor...moderate and major flooding...
Valid Period: 03/18/2024 - 06/16/2024
: Current and Historical
: Chances of Exceeding
: Flood Categories
: as a Percentage (%)
Categorical :
Flood Stages (FT) : Minor Moderate Major
Location Minor Mod Major : CS HS CS HS CS HS
-------- ----- ----- ----- : --- --- --- --- --- ---
:Prairie River
Taconite 10.0 12.0 13.0 : <5 <5 <5 <5 <5 <5
:Mississippi River
Aitkin 13.0 15.0 18.0 : 11 54 <5 33 <5 7
Fort Ripley 10.5 12.5 26.0 : 11 43 <5 20 <5 <5
:St. Croix River
Danbury 7.0 8.5 10.0 : <5 8 <5 <5 <5 <5
:Snake River
Pine City 9.0 10.0 11.0 : <5 10 <5 5 <5 <5
:St. Louis River
Scanlon 10.5 11.0 13.0 : <5 5 <5 <5 <5 <5
:Nemadji River
Nemadji R nr Supe 24.0 26.0 28.0 : <5 <5 <5 <5 <5 <5
:Tyler Forks
Mellen 9.0 10.0 12.0 : 12 35 5 25 <5 5
:Bad River
Odanah 16.0 18.0 20.0 : <5 <5 <5 <5 <5 <5
Odanah 8.5 9.5 10.5 : <5 6 <5 <5 <5 <5
:South Kawishiwi River
Ely 6.5 7.5 8.5 : <5 25 <5 12 <5 <5
:Little Fork River
Little Fork 22.0 24.0 26.0 : <5 <5 <5 <5 <5 <5
:Vermilion River
Crane Lake 14.0 16.0 18.0 : <5 14 <5 <5 <5 <5
Legend
CS = Conditional Simulation (Current Outlook)
HS = Historical Simulation
FT = Feet
In Table 2 below...the 95 through 5 percent columns indicate the
probability of exceeding the listed stage levels (FT) for the valid
time period.
...Table 2--Exceedance Probabilities...
Chance of Exceeding Stages
at Specific Locations
Valid Period: 03/18/2024 - 06/16/2024
Location 95% 90% 75% 50% 25% 10% 5%
-------- ------ ------ ------ ------ ------ ------ ------
:Prairie River
Taconite 3.3 3.5 4.2 5.1 6.0 7.5 8.2
:Mississippi River
Aitkin 5.2 5.7 7.7 9.3 11.7 13.5 14.5
Fort Ripley 4.6 5.1 6.5 7.5 9.2 10.7 12.3
:St. Croix River
Danbury 1.3 1.6 2.2 3.0 4.0 5.0 5.5
:Snake River
Pine City 3.7 4.2 4.8 5.5 6.5 7.8 8.1
:St. Louis River
Scanlon 4.4 4.7 5.2 5.8 6.7 7.7 8.9
:Nemadji River
Nemadji R nr Supe 8.0 9.8 11.6 14.4 18.5 21.9 22.7
:Tyler Forks
Mellen 4.8 5.1 5.7 6.7 7.5 9.3 10.2
:Bad River
Odanah 4.1 4.7 5.4 6.6 7.9 10.9 12.3
Odanah 2.9 3.1 3.5 3.9 4.7 6.4 7.0
:South Kawishiwi River
Ely 3.1 3.5 3.9 4.4 4.9 5.5 5.8
:Little Fork River
Little Fork 3.9 4.1 5.3 6.2 7.3 9.5 12.0
:Vermilion River
Crane Lake 7.3 7.3 8.3 9.7 10.7 11.9 12.5
In Table 3 below...the 95 through 5 percent columns indicate the
probability of falling below the listed stage levels (FT) for the
valid time period.
...Table 3--Nonexceedance Probabilities...
Chance of Falling Below Stages
at Specific Locations
Valid Period: 03/18/2024 - 06/16/2024
Location 95% 90% 75% 50% 25% 10% 5%
-------- ------ ------ ------ ------ ------ ------ ------
:Prairie River
Taconite 3.2 3.1 3.0 2.9 2.7 2.4 2.3
:Mississippi River
Aitkin 5.1 5.0 4.5 3.6 2.6 2.0 1.7
Fort Ripley 4.6 4.6 4.5 4.2 3.8 3.5 3.4
:St. Croix River
Danbury 0.9 0.9 0.9 0.9 0.8 0.8 0.8
:Snake River
Pine City 3.0 3.0 3.0 2.9 2.8 2.8 2.8
:St. Louis River
Scanlon 3.9 3.8 3.6 3.5 3.4 3.3 3.2
:Nemadji River
Nemadji R nr Supe 4.1 4.0 3.9 3.9 3.8 3.7 3.6
:Tyler Forks
Mellen 3.5 3.5 3.4 3.3 3.2 3.1 3.1
:Bad River
Odanah 2.7 2.6 2.6 2.4 2.4 2.3 2.2
Odanah 2.3 2.2 2.2 2.1 2.1 2.0 2.0
:South Kawishiwi River
Ely 2.3 2.3 2.3 2.2 2.2 2.2 2.1
:Little Fork River
Little Fork 3.7 3.6 3.5 3.2 2.9 2.1 1.7
:Vermilion River
Crane Lake 7.0 6.9 6.7 6.4 6.0 5.4 5.2
These long-range probabilistic outlooks contain forecast values that
are calculated using multiple season scenarios from 30 or more years
of climatological data...including current conditions of the
river...soil moisture...snow cover...and 30 to 90 day long-range
outlooks of temperature and precipitation. By providing a range of
probabilities...the level of risk associated with long-range planning
decisions can be determined. These probabilistic forecasts are part
of the National Weather Service`s advanced hydrologic prediction
service.
Visit our web site weather.gov/dlh for more weather and water
information.
For additional information on stream flow conditions for USGS
locations please reference https://dashboard.waterdata.usgs.gov
For additional information on stream flow conditions at MNDNR sites
www.dnr.state.mn.us/waters/csg/index.html
or
www.climate.umn.edu/dow/weekly_stream_flow/stream_flow_weekly.asp
For more information on climate outlooks reference
www.cpc.ncep.noaa.gov
The is the final Spring Flood Outlook of 2024.
$$