Flood Potential Outlook
Issued by NWS Greer, SC
FGUS72 KGSP 062117
WINTER/SPRING FLOOD POTENTIAL OUTLOOK
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
415 PM EST SAT FEB 6 2016
...The latest Winter/Spring Flood Potential Outlook for the
Western Carolinas and Extreme Northeast Georgia calls for a
MUCH ABOVE NORMAL risk for small-stream flooding and an
ABOVE NORMAL risk for mainstem river flooding across the entire
region through early spring 2016...
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. However...this flood season began in early
October and the region has remained wet through the fall and
mid-winter...which means a heightened risk for additional and
more significant flooding on both mainstem rivers and smaller
streams through early spring.
14-DAY OBSERVED PRECIPITATION...
Across the North Carolina foothills and Blue Ridge Escarpment...
precipitation that fell over the past 14-days was 125-200 percent
of normal. This caused widespread minor flooding of small streams
and scattered minor flooding of mainstem rivers.
Across the interior North Carolina Mountains...precipitation was
50-110 percent of normal. This caused scattered minor flooding
of small streams.
Across the Carolina Piedmont...precipitation was 25-90 percent of
normal and no flooding occurred.
Across the Northeast Georgia and extreme Upstate South
Carolina...precipitation was 75-150 percent of normal and only
isolated flooding of small streams occurred.
Across the Northeast Georgia and the South Carolina Upstate...14-day
average streamflows are running ABOVE NORMAL or in the 76-90th
Across the North Carolina Mountains and Foothills...14-day average
streamflows are running MUCH ABOVE NORMAL or above the 90th
percentile along the Blue Ridge Escarpment...French Broad River
Valley...and the Foothill region and ABOVE NORMAL or in the
76-90th percentile elsewhere.
Across the North Carolina Piedmont...14-day average streamflows are
running NEAR NORMAL or in the 50-75th percentile.
Most reservoirs across the region are above their target pools for
this time of year. The high pool levels are generating minor flooding
of some boat ramps...docks...shorelines...and other nearby areas.
A signficant winter storm on January 22 resulted in a deep snowfall
across the North Carolina mountain...foothill...and Piedmont regions.
While that snow has melted...it has helped to keep soil moisture
contents very high. This means that as additional precipitation
occurs...precipitation results in more runoff than normal...generating
more flooding with less precipitation than normal. While not nearly as
substantial...additional snowpack will be produced especially across
the North Carolina mountains over the next 7 days.
1-7 DAY FUTURE PRECIPITATION OUTLOOK and FORECAST...
BELOW-NORMAL precipitation is expected over the next 7 days.
Across the North Carolina foothills and mountain regions...0.25 to
0.50 inches of precipitation is forecasted. Across the Carolina
Piedmont and northeast Georgia...less than 0.25 inches of
precipitation is forecasted. However...much of the precipitation
across North Carolina over the next week will be frozen preventing
runoff from occurring until temperatures start to moderate later
in the period.
8-14 DAY PRECIPITATION OUTLOOK...
NEAR-NORMAL precipitation is expected over the 8-14 day period.
14-30 DAY PRECIPITATION OUTLOOK...
SLIGHTLY ABOVE-NORMAL precipitation is expected over the 14-30 day
90-DAY PRECIPITATION OUTLOOK...
SLIGHTLY ABOVE-NORMAL precipitation is expected over the 90-day period
beginning on February 1.
SHORT-TERM FLOOD FORECAST...
No flooding is occurring at this time and small streams and mainstem
rivers are expected to remain well below Minor Flood stage over the
next 7 days. Reservoir levels will remain near or slightly above
full pool through the period.
LONG-TERM FLOOD OUTLOOK...
Given current antecedent conditions and long-range precipitation
guidance...the potential for excessive runoff is VERY HIGH.
Therefore...the relative flooding risk for small streams is MUCH
ABOVE NORMAL and for mainstem rivers the relative flooding risk is
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
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
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 next outlook will be issued on or by February 19...2016.
For the latest status of streams and mainstem rivers across the region