Flood Potential Outlook
Issued by NWS Jackson, KY

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PROBABILISTIC HYDROLOGIC OUTLOOK
NATIONAL WEATHER SERVICE JACKSON KY
350 PM EST THU FEB 19 2015

This outlook covers eastern Kentucky.

...The flood risk for eastern Kentucky is normal for this time of
year, with at least a minor flooding threat due to rain and snow
melt.

This outlook is valid from February 19 through March 5, 2015.

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:  2/23/2015 - 5/24/2015

                                       :    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
--------           -----  -----  ----- : ---  ---  ---  ---  ---  ---
:Cumberland River
Barbourville        27.0   33.0   38.0 :  50   <5   24   <5   14   <5
Cumberland          12.0   14.0   16.0 :  <5   <5   <5   <5   <5   <5
Pineville         1002.0 1010.0 1019.0 :  24   <5   11   <5   <5   <5
Williamsburg        21.0   27.5   32.0 :  66   <5   33   <5   17   <5
:South Fork Kentucky River
Booneville          27.0   32.0   38.0 :  33   <5   19   <5    9   <5
Oneida              29.0   34.0   38.0 :   8   <5   <5   <5   <5   <5
:Cumberland River
Baxter              16.0   18.0   20.0 :   9   <5    6   <5   <5   <5
:Red River
Clay City           17.0   19.0   23.0 :  23   <5   16   <5   <5   <5
:Russell Fork Big Sandy River
Elkhorn City        21.0   22.0   24.0 :  <5   <5   <5   <5   <5   <5
:Kentucky River
Heidelberg          20.0   24.0   30.0 :  47   <5   11   <5   <5   <5
Ravenna             21.0   25.0   31.0 :  71   <5   47   <5   28   <5
:North Fork Kentucky River
Hazard              20.0   27.0   33.0 :  11   <5   <5   <5   <5   <5
Jackson             29.0   31.0   40.0 :  23   <5   17   <5   <5   <5
:Levisa Fork Big Sandy River
Pikeville           35.0   42.0   50.0 :   6   <5   <5   <5   <5   <5
Prestonsburg        40.0   43.0   46.0 :  <5   <5   <5   <5   <5   <5
Paintsville         35.0   38.0   42.0 :  17   <5   11   <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: 2/23/2015 - 5/24/2015
Location              95%    90%    75%    50%    25%    10%     5%
--------            ------ ------ ------ ------ ------ ------ ------
:Cumberland River
Barbourville         10.6   13.1   20.0   27.3   32.6   40.1   48.8
Cumberland            4.9    5.5    6.3    7.3    8.5    9.6   10.9
Pineville           981.7  982.4  988.2  995.6 1001.5 1010.7 1017.0
Williamsburg         12.4   14.6   19.2   24.3   29.1   35.1   37.3
:South Fork Kentucky River
Booneville           12.0   13.7   16.2   23.1   28.8   37.7   39.7
Oneida               12.7   14.3   16.2   18.8   22.9   28.5   30.2
:Cumberland River
Baxter                3.9    4.3    6.9    9.2   13.0   15.4   18.9
:Red River
Clay City             8.2    9.3   10.2   13.7   16.6   20.7   21.9
:Russell Fork Big Sandy River
Elkhorn City          8.4    9.2    9.7   10.9   12.7   15.1   17.0
:Kentucky River
Heidelberg           15.8   17.0   17.8   19.8   21.8   24.3   26.5
Ravenna              17.7   18.5   20.5   24.3   32.0   38.0   41.6
:North Fork Kentucky River
Hazard                6.4    6.5    9.1   12.4   16.5   20.3   23.0
Jackson               7.4   10.0   13.9   19.1   28.3   33.5   35.8
:Levisa Fork Big Sandy River
Pikeville            11.2   12.8   17.2   24.3   29.8   33.0   35.7
Prestonsburg          8.9   11.5   17.8   25.1   31.5   35.9   37.6
Paintsville           9.6   11.7   19.1   24.6   31.5   38.7   41.1

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.

Ice jams are usually not a factor for flooding in this part of the
country. There is a snowpack across the entire area, containing as
much as an inch and a half of liquid.

So far for the month of February, precipitation has averaged between
2 and 2.5 inches, or slightly below normal. Soil moisture is below
normal. Reservoir levels were near normal and streamflows were below
normal.

A winter storm is forecast to move through the region this weekend,
dropping on average between 2 and 4 inches of snow and sleet, and up
to one quarter inch of ice. In addition, around an inch of rainfall
will be possible through the latter half of the weekend. The
snowpack will absorb some of this liquid, but depending on the exact
temperatures much of the liquid being held in the snowpack could
also be released, leading to the possibility of significant rises on
area rivers. The basins most at risk for running high would be
portions of the Cumberland and Kentucky Rivers.

The 8 to 14 day outlook, valid February 27 through March 5 calls for
temperatures to be below normal and precipitation to be slightly
above normal. Normal highs for this time of year are around 50,
while normal lows are about 32. Normal precipitation for the period
is about 2 inches.

The next spring and water resources outlook will be issued March 5.

Additional supportive data and explanations are available for
precipitation and temperatures forecasts and current soil moisture
data at www.cpc.noaa.gov/products. Current snowpack data are
available at www.nohrsc.nws.gov/nsa. Current streamflow data are
available at waterwatch.usgs.gov/index.php?id=pamap. Visit our web
site weather.gov/jkl for more weather and water information.

$$

Ray





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