Drought Information Statement
Issued by NWS Blacksburg, VA

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AXUS71 KRNK 101354

Drought Information Statement
National Weather Service Blacksburg VA
954 AM EDT Thu Oct 10 2019



Several counties in North Carolina have been added to the Severe
and Moderate drought categories this week including all or
parts of Wilkes, Yadkin and Rockingham counties. Despite some
moderate rainfall across the western mountains over the
past few days, there was no change in drought classifications
across the Blacksburg WFO County Warning Area (CWA).

The October 10th issuance (valid October 8, 2019) of the weekly
U.S. Drought Monitor shows Severe Drought (D2 on the U.S. Drought
Monitor scale) conditions in about a dozen counties in the CWA but
concentrated over southeast West Virginia (WV) and far western
Virginia (VA) and in the NC counties mentioned above. Moderate Drought
(D1 category) covers nearly every other county with a small
area of D0 or Abnormally Dry confined to portions of just a few
counties in the far north.

The fast-emerging drought developed over the past 6 to 8 weeks
and has brought Moderate to Severe drought conditions to nearly the
entire  The extremely dry and hot September and first week of
October has been responsible for this situation.

The categories of drought from the U.S. Drought Monitor are
explained below:

D0 is Abnormally Dry and is the least intense indicator of
drought on scale that ranges from D0 through D4. It indicates
that a region may be entering or emerging from an actual drought.

D1 is Moderate Drought...Conditions that may be associated with
D1 include some crop damage, increased fire risk, falling stream and
reservoir levels and some water shortages. May be thought of as
approximately the 5- to 10-year year drought or the 10 to
20 percent annual chance of occurrence.

D2 is Severe Drought...Crop or pasture damage is likely, fire
risk potentially high, along with low streamflows, water shortages
and possible restrictions. May be thought of as approximately the
10- to 20-year year drought or the 5 to 10 percent annual chance of

D3 is Extreme Drought...Major crop and pasture losses and
widespread water shortages and restrictions. May be thought of as
approximately the 20- to 50-year year drought or the 2 to 5 percent
annual chance of occurrence.

D4 is Exceptional Drought...Widespread crops and pasture losses,
water shortages and water emergencies. May be thought of as
approximately the  50- to 100-year year drought or the 1 to 2
percent annual chance of occurrence.


Impacts to date have been primarily agricultural, with some
crops, fruit and vegetable losses likely and significant loss of hay
production. In addition, fire danger will be on the increase as
the fall season progresses. Outside burn bans have been issued in
numerous counties across the region.

On October 3rd, 2019 the Governor of West Virginia proclaimed a
State of Emergency for the entire state with several water use
restrictions implemented, mostly voluntary at this point.


The past weekend Oct. 6-7, saw a widspread 0.50 to 1.50 inch rainfall
event across the mountains but with far less occurring east of the
Blue Ridge, generally less than 0.10 inches.

The early summer was fairly wet, especially June which was well
above normal at 6.52 inches average (30-year normal is
3.91 inches) across the CWA (65-station COOP network mean).
Pockets of dryness were already evident in June however,
especially across the far west. July was at least near average for
rainfall but with a more sporadic showery rainfall pattern typical of
summer. The July average rainfall across the network was 4.29 inches
versus the long-term mean of 4.41 inches, but with pockets of dryness

August saw a continued downward trend in rainfall with an average
of 2.99 inches versus the long-term normal of 3.78 inches. But there
were more dry areas than earlier in summer, most notably across
southeast West Virginia and far western Virginia where many areas
had less than 50 percent of normal rain.

The bottom fell out in September in terms of both low rainfall
and extreme heat. The network average rainfall was 0.75 inches versus
the normal of 3.82 inches or 20 percent of normal.
It was the second driest September since CWA COOP records began
in 1997 (September 2005 had 0.48 inches). Several COOP stations
measured less than 0.05 inches, including Alderson, WV and the
Danville City COOP with zero rainfall. Aggravating the dryness
was the unusual heat the entire month of September with the
monthly averages +5F to +8F above normal, at levels close to
August normals. Several climate stations had a record warm
September, including Blacksburg and several other were
in the top 2 or 3 warmest, including Lynchburg with the second
warmest September since 1893.


Very light rainfall is possible this weekend with a frontal
passage and less than a tenth of an inch of rain expected.
A modest rainfall event is possible the middle of next week but
details as to amounts remain highly uncertain.

The 6 to 10 and 8 to 14 day outlooks from the NWS Climate
Prediction Center through October 23rd show temperature probabilities
in the above normal range and rainfall probabilities also above
normal across the region.


The USDM Drought categories are based on a number of key
indicators are which are summarized below:

1) Palmer Drought Index (PDSI) 2) CPC Soil Moisture Model 3) USGS
Weekly streamflow percentiles 4) Standardized Precipitation Index
(SPI) 5) Objective Drought Indicator Blends.

Additional indices used include the USDA/NSS topsoil moisture,
the Keetch-Byram Drought Index (KBDI), and NOAA/NESDIS satellite
vegetation index and others. Also considered are various reports
from local, state and federal drought monitoring agencies and
reports from the public.


The Palmer Index is a long-standing measure of relative dryness
or wetness used to quantify drought. The table below shows the most
recent (October 5, 2019) and the one week ago PDSI (9/28) for the six
climate zones that cover all or parts of the Blacksburg CWA. Much
of the rainfall event from October 6-7 did not make it into this

STATE      CLIMATE ZONE     PDSI    Precip to        PDSI
                                    end Drought      9/28

NC          N. MOUNTAINS   -2.31     7.65           -2.08
NC          N. PIEDMONT    -2.83     8.71           -2.59
VA          W. PIEDMONT    -2.63     8.46           -2.42
VA          CENT. MTNS.    -3.05     8.11           -2.82
VA          SW MOUNTAINS   -3.47     8.13           -3.19
WV          SOUTHERN       -4.68     9.63           -4.25

The Palmer Index is calculated weekly and there are seven
categories to indicate dryness or wetness as shown below:

-4.0 or less - Extreme Drought
-3.0 to -3.9 - Severe Drought
-2.0 to -2.9 - Moderate Drought
-1.9 to +1.9 - Near Normal
+2.0 to +2.9 - Unusual Moist Spell
+3.0 to +3.9 - Very Moist Spell
+4.0 or above- Extremely Moist Spell


According the the Climate Prediction Center, soil moisture
deficits over the area range from 40 to 80 mm or 1.5 to 3 inches
and are in the 5th or less percentile in parts of WV and western VA.


The USGS maps of real-time and multi-day streamflows (out to 28-
days) are beginning to reflect the recent dryness due to record
wet conditions in 2018 and into early 2019. Record flows for the date
last week on several West Virginia rivers have seen significant
increases in flows due to the weekend rainfall.


Most groundwater monitoring stations across the region remain
close to normal levels, but are now falling rapidly.
Similar to the stream flows, the record wet 2018 and wet start to
2019 provided many of the groundwater stations with a substantial
cushion which has now disappeared for the most part.


The greatest impacts by far have been in the agricultural sector.
Lost hay production, as well as impacts to vegetables, fruits and some
row crops have been reported around the region. Much of the dryness
was late enough in the season not to have major impacts on row
crops, but grass for livestock is rapidly becoming a concern. Dried up
farm ponds are also causing problems for farmers and livestock


The Fire Danger Risk is moderate to high across most of Virginia
and West Virginia with Keetch-Byram Drought Indices (KBDI) currently
from 400 to over 600 across most of the area. Values above 500
indicate a significant fire danger. Burn bans continue across
most of WV and many parts of VA and NC.


Voluntary water restrictions in the state of WV have been
implemented as noted earlier with sporadic reports of
restrictions in other areas.


Several reservoirs are monitored by the VA Department of
Environmental Quality for drought assessment including Smith
Mountain Lake and Lake Moomaw in the CWA region.
Smith Mountain Lake current elevation is 793.08 feet which is
just above the Drought Watch elevation of 793 feet. Lake Moomaw
remains well above the Drought Watch level of 1565 feet at 1571.09 feet
this  morning. Carvins Cove and Spring Hollow Reservoirs which provide
drinking water to much of the Roanoke area are at 87.3 and 85.5
percent of capacity a small drop since last week.


This product will be updated as necessary as conditions change
but at least once per month.



Additional information on current conditions and forecast drought
may be found at the following websites:

U.S. Drought Monitor...https://droughtmonitor.unl.edu
U.S. Drought Portal...https://www.drought.gov/drought
Climate Prediction Center (CPC)...http://www.cpc.ncep.noaa.gov
U.S. Geological Survey (USGS)...https://waterwatch.usgs.gov
Drought Impact Reporter...http://droughtreporter.unl.edu/map
Southeast Regional Climate Center (VA/NC)...https://sercc.com
Northeast Regional Climate Center (WV)...
Local Weather Information...http://www.weather.gov/rnk


National Weather Service...http://water.weather.gov
US Geological Survey...https://www.usgs.gov/water
US Army Corps of Engineers...http://www.usace.army.mil


The Drought Monitor is a multi-agency effort involving the
National Weather Service and National Centers for Environmental
Information, the USDA, state and regional center climatologists and the
National Drought Mitigation Center. Information for this statement has
been gathered from NWS and FAA observation sites, state cooperative
extension services, the USDA, USACE and USGS.


If you have questions or comments about this Drought Information
Statement, please contact:

Peter Corrigan or Nick Fillo
National Weather Service 1750 Forecast Drive
Blacksburg, VA 24060
Phone: 540-552-1341
Email: rnk.webmaster@noaa.gov


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