Flood Potential Outlook
Issued by NWS Greer, SC

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FGUS72 KGSP 180249
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GAC105-147-119-257-137-241-NCC075-173-113-099-087-175-
115-021-089-149-161-111-199-121-011-023-045-071-109-
035-003-097-119-097-179-025-159-059-SCC001-047-007-
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087-089-115-159-173-175-SCC007-021-045-077-091-
191958-

SPRING FLOOD POTENTIAL OUTLOOK
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
1030 PM EST THU MAR 17 2016

...The latest Spring Flood Potential Outlook downgrades the
risk for flooding region-wide as soils continue to dry and
streamflows continue to decrease during a long-term period
of below-normal precipitation...

...The latest Spring Flood Potential Outlook for the
Western Carolinas and Extreme Northeast Georgia calls for a
BELOW NORMAL to SLIGHTLY ABOVE NORMAL risk for small-stream
flooding and a BELOW NORMAL to NORMAL risk for mainstem river
flooding across the region through early spring 2016...

HISTORICALLY...

The mainstem river flood season typically begins in late December.
The quantity...frequency...magnitude...and significance of river
flood events often increases through late winter with a peak in
early to mid-March. The river flood season typically ends by late
April for the region. While this flood season began early...in
October...and stayed active through early January...flood
occurrences have decreased significantly through mid-March. Above-
normal precipitation observed during past El-Nino winters has not
materialized in 2016. The below-normal rainfall across the entire
region is allowing streamflows to decrease from much-above normal
peaks and is reducing the overall risk for above-normal flooding
through the middle of spring.

14-DAY OBSERVED PRECIPITATION and FLOODING...

Region        Observed    % of      Mainstem    Small Stream
              Precip      Normal    Flooding    Flooding
              (in)

NC Piedmont   0.01-1.10 |   1- 80 | None      | None
NC Foothills  0.10-0.60 |   5- 35 | None      | None
NC Nrn Mnts   0.25-0.90 |  10- 60 | NA        | None
NC Cntl Mnts  0.10-1.50 |  10- 50 | None      | None
NC Srn Mnts   0.40-1.50 |  25- 50 | None      | None

SC Mnts       1.00-2.00 |  40- 80 | NA        | None
SC Foothills  0.50-2.50 |  25-125 | None      | None
SC Piedmont   0.40-2.50 |  20-125 | None      | None

GA NE Mnts/   0.50-1.75 |  15- 75 | None      | None
   Foothills
GA Piedmont   0.25-1.25 |  10- 60 | None      | None


CURRENT STREAMFLOWS...

14-DAY AVERAGE STREAMFLOW STATISTICS BY REGION

Region        % of      % of      %ile    Classification
              Normal    Normal
              (3/4)     (3/17)    (3/17)  (3/17)

NC Piedmont    80-130 |  15-100 |  5-50 | Below Normal
NC Foothills  170-190 |  70-110 | 40-80 | Normal
NC Nrn Mnts   175-200 |  75- 85 | 35-45 | Slightly Below Normal
NC Cntl Mnts  160-225 |  80-100 | 40-60 | Normal
NC Srn Mnts   160-200 |  90-125 | 45-75 | Normal

SC Mnts            NA |      NA |    NA | NA
SC Foothills   65-120 |  75-100 | 35-65 | Normal
SC Piedmont   120-150 |  40- 80 | 30-40 | Slightly Below Normal

GA NE Mnts/   150-175 |  85-125 | 45-80 | Slightly Above Normal
   Foothills
GA Piedmont   100-130 |  75-110 | 45-70 | Normal

14-DAY AVERAGE STREAMFLOW STATISTICS BY PRIMARY RIVER SYSTEM/BASIN

Stream/Basin        % of      % of      %ile    Classification
                    Normal    Normal
                    (3/4)     (3/17)    (3/17)

Broad (GA)          100-130 |  75-110 | 45-70 | Normal
Broad (NC/SC)       120-160 |  75-100 | 30-60 | Slight Below Nrml
Catawba             120-150 |  15-100 |  5-60 | Below Normal
Enoree/Tyger        100-160 |  60-125 | 30-80 | Normal
French Broad        160-210 |  70-110 | 40-70 | Normal
Little Tennessee-   160-225 |  80-140 | 40-80 | Slight Abv Normal
Tuckasegee
Piegon              180-225 |  75- 90 | 40-50 | Normal
Rocky (NC)           90-125 |  20- 75 |  5-40 | Below Normal
Saluda              120-150 |  60-110 | 30-70 | Normal
Tallulah-Chattooga  140-175 | 100-125 | 60-80 | Slight Abv Normal
Toxaway-Keowee-     100-125 |  75-120 | 45-60 | Normal
Savannah


RESERVOIRS...

Most reservoirs across the region are at or slighly above their
target pools for this time of year.


SNOW DEPTH and FORECAST...

Region        Snow   Snow Water  7-Day Snow
              Depth  Equivalent  Forecast
              (in)   (in)        (in)

NC Piedmont   None | None      | None
NC Foothills  None | None      | None
NC Nrn Mnts   None | None      | 0-2
NC Cntl Mnts  None | None      | 0-1
NC Srn Mnts   None | None      | 0-0.5

SC Mnts       None | None      | None
SC Foothills  None | None      | None
SC Piedmont   None | None      | None

GA NE Mnts/   None | None      | None
   Foothills
GA Piedmont   None | None      | None


1-7 DAY FUTURE PRECIPITATION FORECAST and FLOOD POTENTIAL...

Region        7-Day       % of      Mainstem     Small Stream
              Precip      Normal    Flood Ptntl  Flood Ptntl
              (in)

NC Piedmont   0.25-0.50 | 20-66   | Zero       | Zero
NC Foothills  0.25-0.50 | 20-60   | Zero       | Zero
NC Nrn Mnts   0.25-0.75 | 20-100  | NA         | Zero
NC Cntl Mnts  0.25-0.75 | 20-115  | Zero       | Zero
NC Srn Mnts   0.25-0.60 | 15-66   | Zero       | Zero

SC Mnts       0.25-0.50 | 15-40   | NA         | Zero
SC Foothills  0.25-0.50 | 20-40   | Zero       | Zero
SC Piedmont   0.25-0.50 | 20-66   | Zero       | Zero

GA NE Mnts/   0.25-0.50 | 15-40   | Zero       | Zero
   Foothills
GA Piedmont   0.25-0.50 | 20-40   | Zero       | Zero


8-90 DAY PRECIPITATION OUTLOOKS...

Region        8-14 Day          15-30 Day         30-90 Day
              Precip            Precip            Precip
              Outlook           Outlook           Outlook

NC Piedmont   Above Normal    | Slight Abv Nrml | Slight Abv Nrml
NC Foothills  Above Normal    | Slight Abv Nrml | Slight Abv Nrml
NC Nrn Mnts   Above Normal    | Slight Abv Nrml | Slight Abv Nrml
NC Cntl Mnts  Above Normal    | Slight Abv Nrml | Slight Abv Nrml
NC Srn Mnts   Above Normal    | Slight Abv Nrml | Slight Abv Nrml

SC Mnts       Above Normal    | Slight Abv Nrml | Slight Abv Nrml
SC Foothills  Above Normal    | Slight Abv Nrml | Slight Abv Nrml
SC Piedmont   Above Normal    | Slight Abv Nrml | Slight Abv Nrml

GA NE Mnts/   Above Normal    | Slight Abv Nrml | Slight Abv Nrml
   Foothills
GA Piedmont   Above Normal    | Slight Abv Nrml | Slight Abv Nrml

Note that Equal-Chances means there are equal chances for
above-normal...normal...and below-normal precipitation during
the given period.  In other words, there is no clear signal for
precipitation during the given period.


LONG-TERM FLOOD OUTLOOK...

Therefore...given current antecedent conditions and long-range
precipitation guidance...the long-term flood outlook through the
end of April 2016 is as follows...

Region        Runoff            Mainstem          Small
              Potential         Rivers            Streams

NC Piedmont   Below Normal    | Below Normal    | Below Normal
NC Foothills  Normal          | Slight Blw Nrml | Normal
NC Nrn Mnts   Slight Blw Nrml | NA              | Slight Blw Nrml
NC Cntl Mnts  Slight Abv Nrml | Normal          | Slight Abv Nrml
NC Srn Mnts   Slight Abv Nrml | Normal          | Slight Abv Nrml

SC Mnts       NA              | NA              | Normal
SC Foothills  Normal          | Slight Blw Nrml | Normal
SC Piedmont   Slight Blw Nrml | Below Normal    | Slight Blw Nrml

GA NE Mnts/   Slight Abv Nrml | Normal          | Slight Abv Nrml
   Foothills
GA Piedmont   Normal          | Slight Blw Nrml | Normal

ACKNOWLEDGEMENTS...

The precipitation analysis is derived from quality-controlled
gridded precipitation estimates produced at the Lower Mississippi
River Forecast Center /LMRFC/ and the Southeast River Forecast
Center /SERFC/.

The 1-7 day future precipitation is derived from guidance produced
at the Weather Prediction Center /WPC/.

The long-term precipitation outlooks are derived from guidance
produced at the Climate Prediction Center /CPC/.

Streamflow imformation is courtesy of the United States Geological
Survey /USGS/.

Reservoir information is courtesy of Duke Energy...Georgia Power...
and the US Army Corps of Engineers /USACE/.

The general outlook is produced in collaboration with the LMRFC and
the SERFC.


NEXT ISSUANCE DATE...

The next flood outlook will be issued by Friday...April 1st...2016.


LATEST INFORMATION...

For the latest status of streams and mainstem rivers across the region
please visit:

http://water.weather.gov/ahps2/area.php?wfo=gsp&hydro_type=0&hsa_type=1


QUESTIONS or COMMENTS...

This product has undergone several revisions and enhancements during the
most recent flood outlook period.  Additional enhancements are planned
for future flood outlooks. Your feedback and recommendations are
encouraged in order to ensure this product meets user needs.  Please
direct feedback...recommendations...questions...and comments to:

National Weather Service
Weather Forecast Office - Greenville-Spartanburg
1549 GSP Drive
Greer SC 29651
Phone 864-848-9970
joshua.palmer@noaa.gov

$$

JMP



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