Flood Potential Outlook
Issued by NWS Hastings, NE

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Probabilistic Hydrologic Outlook
National Weather Service Hastings NE
310 PM CST Thu Feb 15 2018

...Spring Flood and Water Resources Outlook Number 1...

This outlook is for the Hastings Hydrologic Service Area (HSA). In
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 potential for ice jam flooding in the Loup and Platte River
Basins is above normal this spring, while the overall threat for
spring flooding after the ice is out (and across the other river
basins of south central Nebraska and north central Kansas) will be
near normal...

...Short Term Hydrologic Outlook...February 15th - March 1st...

Temperature and Precipitation Outlook: Temperatures will be on a bit
of a roller coaster ride as we end February with certainly some
milder days, but we also expect a few strong cold fronts that at
times will take us back down to well-below freezing. When we average
the temperatures out, the latter half of February will probably
average near-normal. Precipitation-wise, the weather pattern through
the second half of February appears to be somewhat active with a
general trough pattern across the western United States that
supports a greater likelihood of near to above normal precipitation
for the Plains states. The combination of near normal temperatures
and near to above normal precipitation this time of year would favor
snow over rain as the more likely precipitation type.

Ice jam potential on the Platte and Loup Basins: We`ve been colder
than in recent winters (and colder than normal), and thus our river
ice is currently thicker than normal and thicker than in recent
years. Accumulated freezing degree days is one indicator that can be
used to gauge potential ice thickness. So far this winter in Grand
Island we are at around 800 freezing degree days. The normal value
of freezing degree days for mid-February in Grand Island is just
over 600 and we were somewhere between 425 and 550 freezing degree
days at this point during the past two winters. We`ve received
reports of river ice thickness to around 1 foot in some locations,
which leads to an elevated risk for ice jam flooding once this river
ice begins to break up. Thus far we`ve had sporadic ice jams this
winter, and this threat will continue through the short term as the
thaw and re-freeze cycle continues. We likely will not see a full
fledged river ice break up until sometime in March, which is when our
threat for ice jam flooding will be the greatest. Historically we
typically only see a threat of ice jam flooding within the Loup and
Platte River Basins.

Flooding potential from rain and snow melt: The weather pattern
appears to turn more active as we head into late February, but
precipitation would likely favor snow versus rain. However, if we
were to see any appreciable rainfall on our currently-frozen ground
we could expect most of the rain to run off, leading to an enhanced
flood threat. As of February 15th the frost depth has been running
around 16 inches in thickness. The snow cover we currently have on
the ground across portions of the forecast area has a low enough
liquid content, and will melt slow enough, that it is not expected
to pose a flooding threat.

...Long Term Hydrologic Outlook...March 1st - May 18th...

The latest Drought Monitor indicates that most of our forecast area
generally south of Highway 92 has been abnormally dry. Our soil
moisture for this time of year ranges from a little above normal
north of Highway 92, to near normal for the rest of south central
Nebraska, to slightly below normal across northern Kansas. We expect
late February to be cool enough that the we will still be dealing
with river ice and frozen ground conditions as we head into early
March, which will be a later ice-out than in the past few years.
There are not many good long range forecasting clues this spring and
thus the 3-month precipitation outlook is mainly indicating equal
chances of above, below or near normal precipitation. The Platte
River basin over the Rocky Mountains has experienced a near normal
snow year thus far. The reservoirs on the Platte River are a little
fuller than average, but have plenty of space to handle the expected
spring runoff. Therefore, runoff from spring snowmelt is not
expected to result in flooding concerns this year.

The threat of ice jam flooding will continue to be above normal in
the Loup and Platte River Basins in early March due to our thick
river ice and a later ice-out than in recent years. Ice jam prone
areas will want to closely monitor river ice conditions for possible
ice jams as the ice begins to break up and flow downstream in March.
Any moderate to heavy rainfall events of over 1 inch in early March
prior to ground thaw would also be potentially problematic and
enhance our early March flood potential should they occur. However,
it needs to be noted that heavy rains in early March tend to be
rather rare, but the later we get into March with the frozen ground,
the better the chance climatologically for rain events.

After we thaw the ground and clear the river of ice we should more
or less expect a fairly normal chance for spring flooding through
May. The river flow models indicate some of our rivers may be a hair
above normal and some a bit below, but if you average everything out
across our forecast area, it appears like we are heading towards a
fairly normal spring flood threat.


...Climatological Review (Annual 2017 and More Recent
Winter 2017-18 Precipitation Trends)...

Let`s start with a look back at precipitation totals for the year
2017 across the 30 county NWS Hastings coverage area (24 counties in
Nebraska and 6 in Kansas):

In the most basic sense, 2017 precipitation across the 30-county
area as a whole was not all that different than 2016, meaning that
it was relatively "near-normal". More specifically, the majority of
locations observed annual totals between 85-115 percent of 30-year
normals. In other words, for most places, 2017 as a whole was not
overly-dry or overly-wet. That being said, of course there were some
localized drier and wetter exceptions, and for most all areas, the
last two-and-a-half months from mid-October onward were very dry.

Now here is a closer look at 2017 precipitation totals/trends within
both Nebraska/Kansas portions of the local area (including a
precipitation table below):

Central/South Central Nebraska (24 counties):
Most of the local area measured annual precipitation totals between
85-115 percent of the 30-year normal...meaning generally "near
normal". However, there were of course some drier and wetter
exceptions. On the drier side of things, one of the main areas that
stood out was Fillmore/Thayer counties. In contrast, the overall-
wettest places generally concentrated in two areas: 1) Within a
roughly 20-40 mile wide corridor extending from Franklin/Webster
counties in the south, then northeastward through the Hastings-Grand
Island-Aurora-Osceola-Genoa areas...2) Within the Valley/Sherman
County area. Based on data from around 40 NWS Cooperative Observer
stations, along with a few automated airport sites, a few of the
driest locations (versus normal) included Hebron with 24.54" (6.85
below normal) and Geneva at 27.33 (-1.94). On the opposite side of
the rain gauge, some of the wettest totals (versus normal) included
36.19" at Osceola (7.30 above normal), 31.43" at Loup City (+4.34)
and 30.39" at Grand Island airport (+3.73"). Two of the overall-
wettest months of the year for most areas were May and October (most
of which fell early in the month).

North Central Kansas (6 Counties):
Compared to Nebraska portions of the area, things were overall-drier
here, with at least 70 percent of the area measuring at least
slightly below normal precipitation (the area as a whole generally
ranged from 80-105 percent of normal). The overall-driest conditions
focused within Jewell, Osborne, southeastern Smith and northwestern
Mitchell counties. In contrast, at least slightly above normal
precipitation concentrated within Phillips, northwestern Smith and
northwestern Rooks counties. Based on data from 18 official NWS
Cooperative Observer stations, a few of the wettest sites included
Phillipsburg with 28.59" (3.17 above normal) and Logan with 23.34"
(+0.61). In contrast, a few of the driest stations included Alton (2
miles southwest) with 21.32" (4.81" below normal) and Natoma with
22.06" (-4.23").

2017 Drought recap (entire NWS Hastings coverage area):
According to weekly drought updates by the U.S. Drought Monitor, the
year started out with most of the area in Abnormally Dry (category
D0) conditions, with limited areas of Moderate drought (D1). Thanks
to a fairly wet spring, the entire area became void of all drought
categories by late May, but this only persisted for about one month,
as a somewhat dry June and July (in many areas) brought back a
fairly widespread coverage of Abnormally Dry (D0) that persisted
into early fall. Thanks to widespread early-October rains, the vast
majority of counties again became free of all drought categories for
1-2 months. However, a very dry period from mid-October through the
end of the year brought a return of widespread Abnormally Dry (D0)
in December. Overall though, 2017 featured enough precipitation to
keep Severe Drought (D2) or worse at bay.

The first table below features precipitation totals and departures
from normal/percent of normal for the entire year 2017, with data
depicted for 30 locations scattered throughout the local area. Most
of these stations are NWS Cooperative Observers, along with a few
primary airport sites:


  Location          Precip                            Percent of
North Central KS  All of 2017     Normal   Departure    Normal
--------           --------       ------   ---------  --------
Alton 2SW           21.32         26.13      -4.81        82
Beloit              26.67         27.92      -1.25        96
Burr Oak            23.62         27.06      -3.44        87
Logan               23.34         22.73      +0.61       103
Natoma              22.06         26.29      -4.23        84
Phillipsburg        28.59         25.42      +3.17       112
Smith Center        24.19         25.71      -1.52        94


  Location          Precip                            Percent of
South Central NE  All of 2017     Normal   Departure    Normal
--------           --------       ------   ---------  --------
Aurora 4N           32.63         30.96      +1.67       105
Cambridge           23.63         22.49      +1.14       105
Clay Center         28.49         28.78      -0.29        99
Elwood 8S           25.08         23.43      +1.65       107
Franklin            29.39         26.23      +3.16       112
Genoa 2W            32.43         28.82      +3.61       113
Geneva              27.33         29.27      -1.94        93
Gothenburg          27.02         23.71      +3.31       114
Grand Island Arpt   30.39         26.66      +3.73       114
Greeley             26.57         26.91      -0.34        99
Harlan County Lake  26.91         24.49      +2.42       110
Hastings Airport    30.67         27.11      +3.56       113
Hebron              24.54         31.39      -6.85        78
Kearney Airport     25.54         25.23      +0.31       101
Loup City           31.43         27.09      +4.34       116
Minden              25.37         26.22      -0.85        97
Ord Airport         29.07         24.94      +4.13       117
Osceola             36.19         28.89      +7.30       125
Ravenna             27.69         26.54      +1.15       104
Red Cloud           28.20         30.23      -2.03        93
Shelby 3NE          32.03         26.86      +5.17       119
St. Paul            27.58         26.21      +1.37       105
York 3N             30.23         30.23       0.00       100


Now that we`ve examined precipitation trends/totals for the entire
year 2017, it`s time to take a closer look at more recent
precipitation trends over the past few months, specifically what has
transpired since the start of "meteorological winter" back on Dec.
1st (meteorological winter is defined as the three calendar months
of Dec-Jan-Feb).

As evidenced in the data presented in the table below (and supported
by NWS AHPS precipitation analysis), this winter-so-far has featured
a fair amount of variability in precipitation across the
local 30-county area, but as a whole, roughly two-thirds of the area
has been below normal. The farthest-below-normal locations have
concentrated within southern and southeastern counties, especially
north central Kansas, along with south central Nebraska areas near
the state line and also extending north up Highway 81 into Fillmore
and York counties. In contrast, several Nebraska counties mainly
along/north of Interstate 80 have received at least slightly above-
normal precipitation, largely due to the significant snow
storm/blizzard of Jan. 21-22. For parts of the area, this was the
overall-biggest snow storm in nearly two years, with most counties
north of Interstate 80 seeing 10-14 inches. However, snow amounts
with this storm tapered off sharply south of there, with most places
south of I-80 only averaging 1-4" (with a notable exception of
southern Rooks County KS which saw around 6"). In terms of winter-to-
date extremes, one of the overall driest NWS stations since Dec. 1
has been Beloit KS with merely 0.56" (1.34" below normal). On the
wetter side of the spectrum is Grand Island airport with 2.18"
(0.72" above normal).

Winter drought trends:
According to weekly updates by the U.S. Drought Monitor, much of the
30-county area has remained "stuck" in Abnormally Dry (D0)
conditions since early-mid December. However, several Nebraska
counties mainly northwest of a line from Elwood-Central City have
seen recent improvement to no drought categories whatsoever, while
in the far southeast corner of the coverage area, roughly the
southeast half of Mitchell County KS has been degraded to Moderate
Drought (D1). Keeping things in perspective though, one must keep in
mind that no matter how much precipitation falls during the winter,
it usually only accounts for a small percentage of total annual
precipitation, the vast majority of which falls during the spring
and summer.

This next table below highlights precipitation totals and departures
from normal/percent of normal for meteorological winter thus far,
covering Dec. 1 - Feb. 14. This table features data for 25 locations
scattered throughout the local area, many of which are the same as
found in the 2017 annual table above. Most of these stations are
official NWS Cooperative Observers, along with a few primary airport
sites:

  Location          Precip                            Percent of
North Central KS  Dec 1-Feb 14    Normal   Departure    Normal
--------           --------       ------   ---------  --------
Alton 2SW            0.79          1.78      -0.99        44
Beloit               0.56          1.90      -1.34        29
Burr Oak             1.05          1.77      -0.72        59
Logan                0.98          1.41      -0.43        70
Plainville 4WNW      1.49          1.75      -0.26        85
Smith Center         0.74          1.44      -0.70        51


  Location          Precip                            Percent of
South Central NE  Dec 1-Feb 14    Normal   Departure     Normal
--------           --------       ------   ---------  --------
Cambridge            1.34          1.31      +0.03       102
Clay Center          1.08          1.63      -0.55        66
Elwood 8S            1.05          1.40      -0.35        75
Franklin             0.87          1.55      -0.68        56
Geneva               0.76          1.61      -0.85        47
Grand Island Arpt    2.18          1.46      +0.72       149
Greeley              1.47          1.55      -0.08        94
Hastings Airport     1.21          1.25      -0.04        97
Hebron               1.38          2.05      -0.67        67
Holdrege             1.35          1.36      -0.01        99
Kearney Airport      1.85          1.33      +0.52       139
Loup City            1.55          1.59      -0.04        97
Minden               1.05          1.23      -0.18        85
Ord Airport          1.65          1.21      +0.44       136
Osceola              2.09          1.89      +0.20       111
Ravenna              1.61          1.37      +0.24       118
Shelby 3NE           1.94          1.68      +0.26       115
St. Paul             2.59          1.31      +1.28       198
York 3N              1.31          2.31      -1.00        57


...Weather/Climatological Outlook For The Next Week Through The Next
Three Months...

It`s now time to switch gears and look ahead to expected weather
conditions over the next several days and expected climate trends
over the next several months:

Starting with the most immediate local weather expectations over the
next week (through Feb. 22): According to the latest NWS Hastings 7-
day forecast, the upcoming week looks to feature mostly dry
conditions, along with temperatures fluctuating several degrees
either side of mid-February normals. Precipitation-wise, the only
chances for measurable precipitation appear to focus between Monday
the 19th and Tuesday the 20th, but amounts currently appear quite
meager. Temperature-wise, daily highs will run a wide spectrum
during the next week, ranging from as cold as the 20s (such as
Tuesday the 20th) to as warm as the 50s and 60s (on Sunday the
18th). Putting this in perspective, 30-year normal highs during the
latter part of February typically average somewhere in the low-mid
40s across most of south central Nebraska/north central Kansas.

Looking out a bit farther into the final week of February, the
latest 8-14 day outlook from the Climate Prediction Center (valid
Feb. 22-28) slightly favors an above-normal temperature regime (33-
50 percent chance) and also favors near-normal precipitation.

Looking ahead to the upcoming month of March as a whole, the latest
one-month outlook from the Climate Prediction Center (CPC) released
Feb. 15 favors "equal chances" of seeing above, near or below normal
precipitation during the month, but at least slightly favors below
normal temperatures (33-50 percent chance). However, this still
means there is one-in-three chance (33 percent) that temperatures
could average near normal (within the middle one-third of
climatology), and a lesser (17-33 percent chance) that temperatures
could actually average above normal, or opposite of current
expectations. The "equal chances" forecast for precipitation means
there is no clear signal in current longer-term forecasts to support
one outcomes over another (above normal, near normal, below normal).
However, as a point of reference, normal March precipitation across
the local area ranges from around 1.40" in the western-most counties
(such as Dawson/Furnas), up to around 2.10" in far eastern counties
along and near Highway 81 (such as York/Thayer). Temperature-wise,
long-term 30-year normals (based on 1981-2010 data) indicate that
March high temperatures across South Central Nebraska and North
Central Kansas gradually climb from averages in the mid-40s/near-50
early in the month to the upper 50s/low 60s by month`s end. Average
daily low temperatures gradually increase from around 20 to around
30 degrees.

Turning to the meteorological spring months of March-April-May as a
whole, the latest three-month outlook valid for March-May (released
Feb. 15) shows no truly strong climate signals, with much of the
local area assigned "equal chances" for both temperatures and
precipitation. However, roughly the southwestern one-third to one-
half of the local area very slightly favors (33-40 percent chance)
above normal temperatures and below normal precipitation. Again,
"equal chances" means that long range forecast tools just do not
present enough of a signal to support one of these possible outcomes
over another. Although there are no truly strong signals regarding
upcoming spring precipitation trends, one can keep in mind that 30-
year normal precipitation from March-May 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.

Finally, the latest U.S. Seasonal Drought Outlook (issued by CPC on
Feb. 15 and valid through the end of May) indicates that there are
no strong indications to suggest drought conditions will
degrade/worsen over south central Nebraska and north central Kansas.

(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: http://www.cpc.noaa.gov)


...Long Range 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:  02/17/2018  - 05/18/2018

                                       :    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
--------           -----  -----  ----- : ---  ---  ---  ---  ---  ---
:Little Blue River
Deweese             10.0   16.0   17.0 :   9   14   <5   <5   <5   <5
:North Fork Solomon
Glade               11.0   16.0   18.0 :   7    5   <5   <5   <5   <5
:Bow Creek
Stockton             9.0   12.0   13.6 :   5   <5   <5   <5   <5   <5
:Platte River
Cozad                6.5    8.0   10.0 :  17   19    6    8   <5   <5
Overton              7.5   12.0   14.0 :   8   12   <5   <5   <5   <5
Kearney              7.0    8.0    9.0 :  <5    9   <5    6   <5   <5
Grand Island         6.5    7.0    7.5 :  11   13    7   10    6    7
:Wood River
Gibbon              15.0   16.0   16.5 :  17   18    9   12    8   10
Alda                10.0   11.0   12.2 :  24   25   19   20    9   12
:South Loup River
Ravenna              5.0    8.0   10.0 :  19   22   <5   <5   <5   <5
:Mud Creek
Sweetwater          16.5   18.0   21.0 :  11    8   <5   <5   <5   <5
:South Loup River
Saint Michael        7.5   12.0   15.0 :  11   11   <5   <5   <5   <5
:Middle Loup River
Saint Paul           8.0   10.0   12.0 :  <5   <5   <5   <5   <5   <5
:North Loup River
Saint Paul           7.0   10.0   12.0 :  <5   <5   <5   <5   <5   <5
:Cedar River
Fullerton            9.0   17.0   18.0 :  <5   <5   <5   <5   <5   <5
:Loup River
Genoa               10.5   12.0   13.0 :   6    7   <5   <5   <5   <5
:Beaver Creek
Genoa               15.0   17.0   19.0 :   5    7   <5   <5   <5   <5
:Republican River
Riverton             9.0   10.5   13.5 :  <5   <5   <5   <5   <5   <5
Guide Rock          12.5   15.0   17.0 :  <5   <5   <5   <5   <5   <5
Hardy               11.0   14.0   15.5 :  <5    6   <5   <5   <5   <5
:South Fork Solomon River
Woodston            12.0   16.0   27.0 :  11   20    6   10   <5   <5
:South Fork Solomon
Osborne             14.0   20.0   27.0 :  12   25    5   10   <5   <5
:North Fork Solomon
Portis              15.0   20.0   25.0 :  24   17   14    9   <5   <5
:Solomon River
Beloit              20.0   25.0   30.0 :  18   27   11   10   <5   <5
:Republican River
Cambridge            9.0   10.0   16.0 :  <5   <5   <5   <5   <5   <5
Orleans              9.0   11.0   13.0 :  <5   <5   <5   <5   <5   <5
:Beaver Creek
Beaver City         11.0   13.0   15.0 :  <5   <5   <5   <5   <5   <5
:Sappa Creek
Beaver City         16.0   18.0   20.0 :  <5   <5   <5   <5   <5   <5
Stamford            19.0   22.0   26.0 :  <5   <5   <5   <5   <5   <5
:Prairie Dog Creek
Woodruff            21.0   24.0   30.0 :  <5   <5   <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: 02/17/2018  - 05/18/2018
Location              95%    90%    75%    50%    25%    10%     5%
--------            ------ ------ ------ ------ ------ ------ ------
:Little Blue River
Deweese               4.0    4.2    5.1    7.5    9.1    9.9   13.7
:North Fork Solomon
Glade                 2.9    2.9    2.9    4.5    8.7   10.7   11.3
:Bow Creek
Stockton              3.7    3.7    3.7    3.7    7.0    8.2    8.8
:Platte River
Cozad                 1.8    1.9    3.4    4.5    5.6    7.3    8.1
Overton               3.9    3.9    4.0    4.7    5.4    7.1    8.8
Kearney               2.9    2.9    3.0    3.6    4.7    5.7    6.2
Grand Island          4.3    4.3    4.5    4.7    5.3    6.7    7.7
:Wood River
Gibbon                4.1    4.1    5.8    9.3   11.8   15.8   17.4
Alda                  4.5    4.5    5.6    7.7    9.8   12.0   13.0
:South Loup River
Ravenna               3.0    3.1    3.6    4.2    4.7    5.7    6.2
:Mud Creek
Sweetwater            7.6    8.6    9.6   11.9   13.5   16.7   17.5
:South Loup River
Saint Michael         3.1    3.4    3.9    4.9    5.8    7.7    8.6
:Middle Loup River
Saint Paul            2.6    2.7    3.1    3.4    4.1    4.7    5.7
:North Loup River
Saint Paul            3.3    3.4    3.8    4.3    4.6    5.1    5.2
:Cedar River
Fullerton             4.2    4.4    5.0    5.7    6.3    7.1    7.8
:Loup River
Genoa                 5.3    6.1    7.0    8.0    8.7   10.0   10.9
:Beaver Creek
Genoa                 5.1    5.6    7.2    8.9   10.2   12.2   15.6
:Republican River
Riverton              1.6    1.6    1.8    2.7    3.8    5.1    7.3
Guide Rock            3.5    3.5    3.9    6.2    7.8    9.9   12.0
Hardy                 2.2    2.2    3.5    4.8    6.4    7.7   10.4
:South Fork Solomon River
Woodston              4.3    4.3    4.6    6.1    8.3   12.8   17.6
:South Fork Solomon
Osborne               3.8    3.8    5.0    6.8    8.7   16.3   20.2
:North Fork Solomon
Portis                4.1    4.1    5.8    7.8   14.4   21.5   22.9
:Solomon River
Beloit                3.5    3.5    4.3    7.9   18.1   25.9   29.4
:Republican River
Cambridge             3.4    3.4    3.5    3.6    4.2    6.1    6.4
Orleans               3.2    3.3    3.3    4.0    5.1    7.4    7.7
:Beaver Creek
Beaver City           2.7    2.7    2.7    2.8    4.5    7.7   10.4
:Sappa Creek
Beaver City           2.8    2.8    2.8    2.9    4.1    7.9   11.4
Stamford              6.8    6.8    6.8    7.2    9.7   11.8   13.3
:Prairie Dog Creek
Woodruff              1.2    1.2    1.2    3.5    6.8    8.7   11.8

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: 02/17/2018  - 05/18/2018
Location              95%    90%    75%    50%    25%    10%     5%
--------            ------ ------ ------ ------ ------ ------ ------
:Little Blue River
Deweese               2.4    2.4    2.4    2.2    1.8    1.8    1.8
:North Fork Solomon
Glade                 2.9    2.8    2.7    2.5    2.4    2.3    2.3
:Bow Creek
Stockton              3.6    3.6    3.6    3.5    3.5    3.4    2.9
:Platte River
Cozad                 1.7    1.3    0.5    0.5    0.5    0.5    0.5
Overton               3.6    3.6    3.5    3.0    2.6    2.6    2.6
Kearney               2.6    2.6    2.5    2.0    1.3    1.2    1.2
Grand Island          4.1    4.1    4.0    3.8    3.2    3.1    3.1
:Wood River
Gibbon                4.0    4.0    4.0    4.0    4.0    4.0    4.0
Alda                  4.3    4.3    4.3    4.3    4.3    4.3    4.3
:South Loup River
Ravenna               2.6    2.6    2.6    2.6    2.5    2.5    2.5
:Mud Creek
Sweetwater            6.7    6.7    6.6    6.5    6.4    6.4    6.4
:South Loup River
Saint Michael         2.5    2.5    2.5    2.4    2.3    2.3    2.3
:Middle Loup River
Saint Paul            2.4    2.3    2.3    2.2    2.2    2.1    2.1
:North Loup River
Saint Paul            3.2    3.2    3.1    3.0    2.9    2.8    2.8
:Cedar River
Fullerton             3.1    3.1    3.1    3.0    2.8    2.7    2.6
:Loup River
Genoa                 3.6    3.6    3.6    3.6    3.6    3.6    3.6
:Beaver Creek
Genoa                 3.7    3.7    3.7    3.6    3.5    3.5    3.4
:Republican River
Riverton              1.6    1.6    1.6    1.5    1.5    1.5    1.5
Guide Rock            2.6    2.3    2.3    2.3    2.3    2.3    2.3
Hardy                 1.9    1.8    1.0    1.0    1.0    1.0    1.0
:South Fork Solomon River
Woodston              4.3    4.3    4.2    4.2    4.2    4.2    4.2
:South Fork Solomon
Osborne               3.8    3.8    3.8    3.8    3.8    3.8    3.8
:North Fork Solomon
Portis                4.1    4.0    4.0    4.0    4.0    4.0    4.0
:Solomon River
Beloit                3.4    3.4    3.2    3.1    2.9    2.8    2.8
:Republican River
Cambridge             1.9    1.9    1.7    1.4    1.4    1.4    1.4
Orleans               1.8    1.8    1.6    1.2    1.1    1.0    1.0
:Beaver Creek
Beaver City           2.7    2.6    2.5    2.2    2.2    2.2    2.2
:Sappa Creek
Beaver City           2.8    2.8    2.8    2.8    2.8    2.8    2.8
Stamford              6.5    6.4    6.3    5.8    5.8    5.8    5.8
:Prairie Dog Creek
Woodruff              1.2    1.2    1.2    1.2    1.2    1.2    1.2

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.


...Future Outlooks...

An updated spring flood outlook will be issued Thursday, March 1st.

&&

Visit our local NWS office website for current weather/hydrological
and climate information for South Central Nebraska and North Central
Kansas at: www.weather.gov/hastings

Additional climate information for the region can be obtained at:
www.hprcc.unl.edu

Additional information on climatological outlooks can be found at:
www.cpc.ncep.noaa.gov

Further information on drought conditions can be obtained at:
www.drought.gov www.drought.unl.edu www.droughtmonitor.unl.edu

Information on mountain snowpack can be found at:
www.wcc.nrcs.usda.gov/ftpref/downloads/wsf/201802wsfwww.pdf
www.wcc.nrcs.usda.gov

NWS AHPS precipitation analysis maps can be found at:
http://water.weather.gov

National snow analysis page can be found at: www.nohrsc.noaa.gov/nsa

Soil Moisture:
www.cpc.ncep.noaa.gov/products/Soilmst_Monitoring/US/Soilmst/Soilmst.
shtml

Reservoir Levels: www.usbr.gov/gp/hydromet/curres_google.htm

For training on NWS probabilistic graphics:
www.youtube.com/watch?v=pSoEgvsnpv4

For training on NWS river forecast graphics:
www.youtube.com/watch?v=psIByj8EZY0

$$

Wesely/Pfannkuch




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