Flood Potential Outlook
Issued by NWS Wakefield, VA

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FGUS71 KAKQ 151959

Winter/Spring Flood Potential Outlook
National Weather Service WAKEFIELD VA
359 PM EDT Thu Mar 15 2018

...Sixth Winter/Spring Flood Outlook for 2018...

...River Flood Potential is normal to below normal through March

Each winter and early spring, the National Weather Service office
in Wakefield, VA issues a series of flood potential outlooks.
These outlooks estimate the potential for river flooding across
the Wakefield Forecast Office`s Hydrologic Service Area (HSA).
The HSA includes Central and Eastern Virginia, the Lower Maryland
Eastern Shore, and portions of Northeast North Carolina. The
outlook is based on the current assessment of hydrometeorological
factors which contribute to river flooding. These factors
include, but are not limited too recent precipitation, soil
moisture, snow cover and snow water equivalent, stream flows,
river ice and expected future weather conditions.

In this part of the Mid-Atlantic Region, heavy rainfall is the
primary factor that leads to river flooding. Heavy rainfall can
rapidly cause river flooding at anytime of the year, even when
overall river flood potential is considered low.

The following is a summary of the current conditions as of 3 PM
Thursday March 15 2018:

Current flooding - No rivers are currently in flood as of 2 PM
Thursday March 15 2018.

Recent precipitation - Over the last 30 days from February 14
2018 to March 15 2018, the precipitation has ranged from 1.5" to
4". These totals ranged from near normal to as much as 2" below
normal. The highest totals were observed over the Virginia
Tidewater and Northeastern North Carolina while the lowest totals
were mainly north and west of Richmond including the Central
Virginia Piedmont.

Looking back to the beginning of the water year through March
15th, the rain totals generally range from 10"- 15" with a more
widespread band of 15" - 20" that stretch in an east to west band
from Louisa VA to Wallops Island VA. These totals generally range
from near normal to as much as 6" - 8" below normal. The highest
total recorded for the water year to date is from the Cooperative
observer in Salisbury MD, who recorded 19.59" through March 7 2018
and at Wallops Island, VA with 18.37" of precipitation, which is
1.35" above normal.

Snow conditions - Currently there is no snow on the ground in the
Wakefield HSA.

River ice conditions - Currently there is no ice on area rivers.

Stream Flow Conditions - The 14 day average stream flows continue
to run below to much below normal across Virginia with two sites
at low values for the 14 day period at Farmville and at the gage in
Fluvanna County on the Hardware River. Across the Lower Maryland
Eastern Shore and the Chowan Basin in NC, those gages were
reporting normal 14 day average flows.

When looking at the real time flows as of 1 PM March 15th, the
streamflows look similar to the 14 day flow with most of Virginia
with low flows and the other states gages showing flows in the
normal range.Here are some real time stream flows as of 1 PM
March 15th:

PALMYRA VA  211 CFS/ 828 CFS/ 25.5
CARTERSVILLE VA    3450 CFS/9720 CFS/ 35.5
RICHMOND VA    3960 CFS/9120 CFS/ 43.4
    FARMVILLE VA   133 CFS/ 286 CFS/    46.5
MATTOAX VA     293 CFS/ 753 CFS/ 38.9
    MATOACA VA     479 CFS/1270 CFS/ 37.7
    RAWLINGS VA     151 CFS/    312 CFS/    48.4
    STONY CREEK VA     334 CFS/    640 CFS/    52.2
    SEBRELL VA    1000 CFS/   1870 CFS/    53.5
    LAWRENCEVILLE VA      274 CFS/    495 CFS/    55.4
    EMPORIA VA      352 CFS/    737 CFS/    47.8
    FRANKLIN VA     601 CFS/    919 CFS/    65.4
    BOWLING GREEN VA      93 CFS/    302 CFS/    30.8
    BEULAHVILLE VA     321 CFS/    792 CFS/    40.5
    WILLARDS MD      83 CFS/     91 CFS/    91.2
    UNION NC     475 CFS/    302 CFS/   157.3

Soil Moisture Conditions - Normal to below normal.

Soil moisture indicators including the Palmer Drought Severity
Index, which is used to infer deep soil moisture and long term
drought, shows that as of March 10 2018 the Wakefield HSA, is
depicted as being near normal for deep soil moisture.

The CPC Soil Moisture Monitor, which looks more at top soil
moisture, is showing a very similar pattern since the last update
10 day ago. Deficits along the coast range from 20mm - 40mm below
normal to near 80mm in the South Central VA Piedmont.


Ground water levels across the HSA are in the normal range along
the coastal portions of the Wakefield HSA. However, further
inland across Virginia, including the Piedmont counties, the
ground water levels are running below normal to much below
normal. With the rainfall that fell early in February, the gauges
showed water levels on the rise and that recharged had begun.
However, looking at those gauges now it appears as if that
recharge has stalled. More rain will be needed to get the
groundwater levels back near normal levels generally west of I-95
back to west into the VA Piedmont.

Reservoirs - Normal to Below normal pool levels

Most major reservoirs water storage are near normal levels for
this time of year.

Future Precipitation...There are two opportunities for
precipitation over the next 7 days. The first system would impact
the region on Saturday as a wave of low pressure slides east from
the Western Ohio Valley across NC by Saturday night. The second
and more likely a heavier event would impact the region on Monday
night and linger through mid week as a complex low pressure system
impacts the region. Current forecast predict rainfall amounts up
to 1.25" for the next 7 days.

The latest CPC 8 to 14 day outlook for March 22 - 28 2018 is
indicating below normal temperatures and above normal
precipitation for the 7 day time period.

Lastly, for the 3 month outlook for April through June, the
precipitation forecast is for near normal to above normal while
for temperatures the forecast is for above normal conditions.


The river flood potential through March 29 2018 across the
Wakefield HSA is normal to below normal for this time of year.
Again, remember that heavy rainfall is the most common cause of
river flooding in the Mid-Atlantic States. However river flooding
can be exacerbated when heavy rain is combined with snow melt.

This will be the last flood outlook issued for this year unless
conditions warrant an additional update. The winter/spring flood
outlooks will resume in January 2019.

For additional weather or hydrologic information, please visit
our website at WWW.WEATHER.GOV/AKQ.



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