Flood Potential Outlook
Issued by NWS Wakefield, VA
FGUS71 KAKQ 162139
WINTER/SPRING FLOOD POTENTIAL OUTLOOK
NATIONAL WEATHER SERVICE WAKEFIELD VA
439 PM EST Thu Feb 16 2017
...Fourth winter/spring flood outlook for 2017...
...River Flood Potential is near normal to below normal through
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 Thursday
February 16 2017:
Current Flooding - No rivers are currently in flood as of 2 PM
Thursday February 16 2017.
Recent precipitation - Over the last 30 days, from January 17
2016 - February 16 2017, rainfall totals across the HSA have
ranged from 1" - 2" across Southeastern VA, the Northern Neck of
VA, the Lower Maryland Eastern Shore and Northeastern North
Carolina. The precipitation in these areas is between 1" -3" below
normal. The remainder of the area saw 2" - 4" in this same time
period with these totals ranging from near normal to as much as 2"
Looking at precipitation totals at longer time steps...The 60 day
time frame from December 19 TO February 16 shows precipitation
totals ranged from 3 - 7.5 inches. These values range from near
normal to 4 inches below normal.
For the current water year from October 1 2016 to February 16
2017 the area is divided with portions of Southeast Virginia,
coastal parts of the Delmarva and Northeastern North Carolina
reporting 15 - 24 inches of rain while the remainder of the HSA
saw much less rain with only 9 - 18 inches. The totals in
Southern VA and Northeastern NC were as much as 5 - 8 inches
above normal, while the other areas was on the negative side with
totals ranging from near normal to as much as 5 inches below
Snow Conditions - There is currently no snow on the ground across
the HSA as of 2 PM Thursday February 16th.
River ice conditions - There is currently no snow on the ground
across the HSA as of 2 PM Thursday February 16th.
Stream flow conditions - The 14 day average stream flows, through
February 16th, were in the normal to much below normal range
across the entire hydrologic service area. Over the last two
weeks, the average stream flows have been steady decline as
rainfall has been limited.
When looking at the real time flows as of 2 PM February 16th, the
river levels are mainly in the below normal to much below normal
range for this time of year. Here are some real time stream flows
as of 1 PM February 16th:
Location Observed Level/Median Flow/Percentage of Median
Palmyra VA 123 CFS/ 696 CFS/ 17.7
Cartersville VA 3310 CFS/7080 CFS/ 46.8
Richmond VA 3170 CFS/7300 CFS/ 43.8
Farmville VA 153 CFS/ 283 CFS/ 54.1
Mattoax VA 309 CFS/ 775 CFS/ 39.9
Matoaca VA 579 CFS/ 1250 CFS/ 46.3
Rawlings VA 179 CFS/ 341 CFS/ 52.5
Stony Creek VA 286 CFS/ 713 CFS/ 40.1
Sebrell VA 535 CFS/ 2230 CFS/ 24.0
Lawrenceville VA 232 CFS/ 525 CFS/ 44.2
Emporia VA 298 CFS/ 775 CFS/ 38.5
Franklin VA 273 CFS/ 1020 CFS/ 26.8
Bowling Green VA 129 CFS/ 286 CFS/ 45.1
Beulahville VA 353 CFS/ 747 CFS/ 47.3
Willards MD 58 CFS/ 99 CFS/ 58.6
Union NC 68 CFS/ 318 CFS/ 21.4
Soil Moisture Conditions - NEAR NORMAL TO ABOVE NORMAL.
Soil moisture indicators including the Palmer Drought
Severity Index, which is used to infer deep soil moisture, shows
that, as of February 11th, the entire hydrologic service area,
HSA, is depicted as being near normal for deep soil moisture.
The CPC Soil Moisture Monitor, which looks more at top soil
moisture, shows a significant change from just two weeks ago.
Eastern North Carolina, Southeastern Virginia and the Delmarva
show normal conditions for top soil moisture. However, areas along
and west of Interstate 95 into the Central VA Piedmont and
Northern Neck of VA are now showing top soil moisture deficits of
-20mm - -40 mm. Each area described here is a decrease in moisture
by one category from just two week ago.
Ground Water - Normal to Below Normal Levels.
Ground water levels across the HSA are reporting water levels in
the normal to below normal range across the region. The trend in
the ground water levels has been dropping across the HSA. Normally
this is a time of the year where ground water levels are rising as
the system recharges, but with the lack of rain ground water
levels continue to fall across the HSA
Reservoirs - Normal Pool Levels
Area reservoir pool levels are in the normal range for this time
Future Precipitation...There are two chances for rain in the next
7 days. A weakening low pressure system moves into the region late
Saturday night into Sunday with a chance for some light showers,
but forecast amounts right now are generally less than a tenth of
an inch. The next chance for rain is a little more uncertain, but
would not come until the second half of next week with amount
again most likely remaining less than 0.25 inches.
The latest CPC 8 TO 14 DAY Outlook for February 24 - March 2 2017
is indicating above normal temperatures for the period with
precipitation expected to be above normal.
Lastly for the 3 month outlook for March through May, the
precipitation forecast to have an equal chance of being below
normal, near normal, or above normal and the temperatures have a
higher chance of being above normal.
The river flood potential outlook through March 2 2017 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.
The next outlook will be issued on March 2 2017, unless
conditions warrant an additional update.
For additional weather or hydrologic information, please visit our
website at WWW.WEATHER.GOV/AKQ.