...Spring Flood and Water Resources Outlook Number 2...
This outlook is for the NWS Paducah service area. It covers the time
period for mid-February through mid-May. It includes the mid-
Mississippi and lower Ohio Rivers and their tributaries for
southwest Indiana, southern Illinois, west Kentucky and southeast
Missouri.
...Flood Outlook Highlights...
Flood potential is above average or above normal for much of the
Ohio and Mississippi basins and their tributaries across southern
Illinois, southwest Indiana, southeast Missouri and west Kentucky.
Flooding in this region occurs mainly due to conditions of ground
moisture, river flows, and expected precipitation. Ice jams are
rarely a factor in flooding for this part of the country.
...Current Conditions...
Snow...Frost and Soil Conditions...Precipitation since last fall has
been above normal. 125% to 150% of normal rain has fallen over the
last year. Periodic rounds of heavy rain have fallen since December 1
producing rivers that are continuing to run above normal across the
region. Minor to moderate flooding has already occurred across the
region in January and February of this year. Parts of the Ohio River
remain above flood stage.
Snow is confined to only the extreme northern parts of the
Mississippi and Ohio River Basins where liquid water equivalents are
running from 3 to 6 inches. Frost depths are near normal for this
time of year with no frost depth reported in the service area. Soil
moisture is much above normal and conditions are nearly saturated
across the region.
Given all these factors, flood risk remains above normal across the
region. Additional flooding through the spring will be dependent on
how the snow melts in the upper parts of the Mississippi and Ohio
basins as well as the track of spring storm systems. Elevated river
levels can be expected into at least the first part of spring.
...Probabilistic Outlooks...
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: 03/03/2020 - 06/01/2020
: 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
-------- ----- ----- ----- : --- --- --- --- --- ---
:Green River
Calhoun 23.0 26.0 32.0 : 51 41 39 28 <5 7
Paradise 380.0 386.0 400.0 : 79 71 35 36 <5 <5
:Little Wabash River
Carmi 27.0 32.0 35.0 : 76 68 52 39 29 21
:Ohio River
Evansville 42.0 48.0 52.0 : 27 30 <5 <5 <5 <5
Golconda 40.0 49.0 55.0 : 47 48 6 7 <5 <5
Mount Vernon 35.0 45.0 52.0 : 73 70 <5 8 <5 <5
Newburgh Dam 38.0 48.0 56.0 : 84 81 <5 5 <5 <5
Owensboro 40.0 44.0 49.0 : 35 37 <5 9 <5 <5
Shawneetown 33.0 43.0 53.0 : 81 84 35 38 <5 <5
J.T. Myers Dam 37.0 49.0 60.0 : 77 77 7 8 <5 <5
:Patoka River
Princeton 18.0 20.0 23.0 : 77 62 56 48 21 19
:Skillet Fork River
Wayne City 15.0 17.0 20.0 : 49 43 42 36 32 25
:Wabash River
New Harmony 15.0 20.0 23.0 : 87 84 37 26 <5 <5
:Black River
Poplar Bluff 16.0 19.0 21.0 : 38 22 <5 <5 <5 <5
:Current River
Doniphan 13.0 18.0 22.0 : 33 18 8 <5 <5 <5
Van Buren 20.0 23.0 27.0 : 9 13 <5 <5 <5 <5
:St. Francis River
Fisk 20.0 22.0 26.0 : 23 22 18 19 9 9
Patterson 16.0 25.0 32.0 : 62 60 12 12 <5 <5
:Big Muddy River
Plumfield 20.0 27.0 34.0 : 56 59 20 17 6 <5
Murphysboro 22.0 28.0 36.0 : 84 72 47 39 18 16
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: 03/03/2020 - 06/01/2020
Location 95% 90% 75% 50% 25% 10% 5%
-------- ------ ------ ------ ------ ------ ------ ------
:Green River
Calhoun 16.0 16.5 17.5 23.2 29.8 30.9 31.9
Paradise 377.0 378.5 380.5 383.4 387.8 392.6 395.5
:Little Wabash River
Carmi 19.0 22.1 27.4 32.3 35.4 36.4 37.4
:Ohio River
Evansville 30.3 33.6 36.0 40.2 42.1 43.1 44.3
Golconda 34.4 35.2 36.8 39.5 43.4 46.4 49.5
Mount Vernon 29.4 32.2 34.6 38.9 41.1 42.6 44.9
Newburgh Dam 32.4 36.7 39.7 42.5 44.3 45.2 46.0
Owensboro 29.5 32.8 35.5 38.3 41.2 42.5 43.7
Shawneetown 29.5 31.2 34.2 39.4 45.2 47.0 50.3
J.T. Myers Dam 32.9 34.8 37.4 41.5 45.3 47.1 50.0
:Patoka River
Princeton 15.3 15.9 18.3 20.5 22.3 25.1 25.5
:Skillet Fork River
Wayne City 9.3 10.3 11.7 14.7 22.0 23.8 24.9
:Wabash River
New Harmony 13.9 14.5 17.5 19.2 20.7 21.8 22.6
:Black River
Poplar Bluff 8.8 9.6 10.3 10.7 11.2 17.5 18.7
:Current River
Doniphan 5.0 5.2 7.2 10.0 13.2 17.3 20.7
Van Buren 5.2 5.6 6.4 7.5 10.7 14.3 18.5
:St. Francis River
Fisk 12.1 12.3 12.7 15.4 18.1 25.7 27.0
Patterson 7.2 7.9 12.6 17.2 21.0 26.2 28.2
:Big Muddy River
Plumfield 15.7 17.1 18.7 21.3 23.9 30.5 34.7
Murphysboro 19.2 21.5 23.5 27.3 34.8 39.8 42.3
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: 03/03/2020 - 06/01/2020
Location 95% 90% 75% 50% 25% 10% 5%
-------- ------ ------ ------ ------ ------ ------ ------
:Green River
Calhoun 12.6 12.3 11.8 11.2 10.5 10.2 10.1
Paradise 368.3 368.1 366.8 365.9 364.6 364.3 364.2
:Little Wabash River
Carmi 8.5 7.5 4.8 4.0 3.5 3.3 3.3
:Ohio River
Evansville 17.0 16.2 15.5 14.8 14.3 14.0 13.9
Golconda 29.9 29.7 29.6 29.6 29.6 29.6 29.6
Mount Vernon 24.0 23.9 23.7 23.6 23.5 23.4 23.4
Newburgh Dam 17.1 16.8 16.0 15.1 14.4 13.9 13.6
Owensboro 19.0 19.0 19.0 19.0 19.0 19.0 19.0
Shawneetown 18.9 17.9 17.2 16.2 15.9 15.6 15.4
J.T. Myers Dam 19.9 18.4 17.2 15.6 15.0 14.2 13.7
:Patoka River
Princeton 9.8 8.9 7.4 6.2 4.2 3.4 3.2
:Skillet Fork River
Wayne City 5.6 5.5 5.4 5.4 5.3 5.3 5.3
:Wabash River
New Harmony 7.2 6.3 4.9 3.7 3.2 2.5 2.3
:Big Muddy River
Plumfield 11.6 11.2 10.0 8.9 7.7 6.8 6.4
Murphysboro 13.9 12.8 11.6 10.0 7.1 4.9 4.5
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.
...Weather Outlooks...
A warm up will take place this weekend in advance of the next storm
system. Warm southerly winds will bring abundant moisture back into
the region. Current models indicated a broad swath of 2 to 4 inches
across the entire area falling in a time period between Sunday night
and Wednesday. South of the Ohio River, 3 to 6 inches of rain may
fall.
The 8 to 14 day outlook for March 6 through 12 calls for above
normal temperatures and normal to above normal precipitation. During
this time, normal average temperatures are in the mid 40s and
rainfall during this period is a little over three-quarters of an
inch.
The Outlook for March calls for below normal chances for
precipitation across the region. Normal precipitation for March is
between and 4 and 4 1/2 inches. The outlook for March through May
calls for above normal precipitation.
Visit our web site weather.gov/pah for more weather and water
information.
The next outlook will be issued on March 12 2020.
$$
Lamm
Follow us on Twitter
Follow us on Facebook
Follow us on YouTube
PAH RSS Feed