**November 2006 NC Weather Review**

**Overview**

November 2006 turned out to be much wetter and warmer than normal
throughout much of North Carolina. However, November 2006 will be
remembered most for a deadly F3 tornado that struck the small community
of Riegelwood, in Columbus County, during the early morning hours on
November 16. Eight people were killed, 20 people injured, and 30 homes
were destroyed. Additional information can be found at the following
link:

<http://www.erh.noaa.gov/ilm/Nov162006tornadoes/>

The storm system that produced the tornado was just one of four major
storms to affect North Carolina during November. Each of the four
systems brought a round of heavy rain to the state, yet the two most
memorable will be remembered for the destructive winds that they
unleashed. In addition to the November 16^th^ storm system that produced
the F3 tornado in Columbus County, another much different storm produced
destructive winds just prior to Thanksgiving. A strong and winter-like
nor'easter buffeted the coast with damaging winds and coastal flooding
on November 21 and 22. This storm was responsible for producing wind
gusts to between 50 and 80 MPH along the coast and downing trees as far
west as the Piedmont region. The rainfall tallies produced by the four
storms combined totaled between 5 and 9 inches across the state -
generally 3 to 6 inches above normal. The monthly rainfall across the
state is plotted in figure 1.

![](media/image1.png){width="6.979166666666667in" height="3.96875in"}

**Figure 1. Estimated rainfall for November 2006. Plotted data was
recorded by National Weather Service observation systems or cooperative
observers.**

![](media/image2.png){width="7.010416666666667in"
height="3.4270833333333335in"}

**Figure 2. Average monthly temperatures during November 2006 across
North Carolina.**

The statewide November average temperatures generally ranged between 50
and 55 degrees, except cooler 40s over the Mountains and northern
Foothills, and warmer readings near 60 along the Outer Banks. These
readings averaged about 1 to 3 degrees above the 30 year normal. The
average monthly temperatures from selected stations across North
Carolina are plotted in figure 2.

**Details**

**November 2006 Precipitation**

The four moisture laden storms that affected the state in November sent
the monthly rainfall totals to well above normal levels. The final
November rainfall totals across the state of North Carolina generally
ranged from 5 to 9 inches. The rainfall totals ranged between 4 an 6
inches above normal over much of central and eastern North Carolina (150
to 300 percent of normal), and between 3 and 6 inches over the southwest
Mountains (100 to 125 percent of normal). Raleigh-Durham recorded 9.03
inches of rain for a new November monthly rainfall record. The previous
wettest November in the Raleigh-Durham area was 8.22 inches, recorded in
1948. The heavy rainfall led to river flooding of minor to moderate
intensity across central and eastern North Carolina during the latter
half of the month. The area lakes, which had suffered with well below
normal levels earlier in 2006, filled to well above normal levels by the
end of November.

The rainfall distribution for November was dominated by the four
aforementioned storms. These storms affected the state with the most
significant rain on or around November 7-8, November 11-12, November
15-16, and November 20-22. The rainfall totals were not evenly
distributed across the state. The heaviest rainfall totals were recorded
over portions of central North Carolina, where amounts reached 7 to 9
inches. Portions of the southwestern Mountains around Cherokee, Murphy,
and Robbinsville, totaled only 2 to 4 inches. Figure 3 is a comparison
of observed versus normal rainfall for selected NWS sites across the
state. Most areas were well above their 30 year rainfall average for
November.

![](media/image3.wmf){width="5.583333333333333in"
height="3.8020833333333335in"}

**Figure 3. Comparison of observed precipitation and normal
precipitation for November 2006 at selected locations across North
Carolina.**

**November 2006 Temperatures**

The monthly temperatures averaged in the 50s, except 40s over the
Mountains and near 60 on the Outer Banks. These readings generally
averaged one to three degrees above normal throughout North Carolina.
The warmest areas were found across the northern and central portions of
the state, including Greensboro (+2.3 degrees), Raleigh-Durham (+2.0
degrees), and Elizabeth City (+1.7 degrees). The southwestern and
southeastern corners of the state averaged closer to normal. For
example, the monthly average temperature at Asheville was only 0.6
degrees above normal, while Wilmington was right at the 30 year normal.

The month of November began with a cold shot of air on November 2-3.
This cold spell brought the first freeze to many areas of central and
eastern North Carolina. The Mountains and northwestern Piedmont already
had recorded freezing temperatures in mid October, ending the growing
season for 2006 in those locales.

Following the cold spell, the temperatures warmed to above normal levels
from November 7-16. In fact, new daily record highs were set at both
Greensboro and Raleigh-Durham on November 10 and 11. Raleigh-Durham
reached 81 on the 10^th^ and 80 on the 11^th^ for new daily records. The
warm spell ended with the passage of a strong cold front during the
morning of the 16^th^, which was the morning of the infamous F3 tornado
in Columbus County.

Figure 4 is a water vapor satellite image with the 15 minute
cloud-to-ground lightning data superimposed, valid at 6:25 AM EST on
November 16. This image was taken about 12 minutes before an F3 tornado
reportedly touched down in Riegelwood, at 6:37 AM EST. The orange colors
represent progressively colder cloud tops, which are often indicative of
clouds extending to high altitudes in the atmosphere. There was a large
supercell thunderstorm visible over eastern Bladen County. This storm
had formed earlier over the Gulf Stream waters off Myrtle Beach, South
Carolina, and had moved north-northeast to the position shown in the
figure below. It was only a few minutes later that an F3 tornado ravaged
Riegelwood in southeastern Columbus County.

![](media/image4.png){width="6.997222222222222in"
height="4.924305555555556in"}

**Figure 4. Water vapor satellite imagery and 15 minute cloud-to-ground
lightning plot valid 6:25 AM, November 16, 2006.**

Once the cold front passed offshore during the 16^th^, colder air once
again returned to the state. A strong nor'easter developed along the
southeastern coast of the U.S. on November 20^th^. This system buffeted
much of central and eastern North Carolina with wind and rain on the
21^st^ and 22^nd^. Figures 5 and 6 depict the storm total rainfall and
the peak wind gusts associated with the nor'easter of November 21-22,
2006.

![](media/image5.png){width="7.09375in" height="3.3541666666666665in"}

**Figure 5. Storm total precipitation from the November 21-22, 2006
nor'easter.**

![](media/image6.png){width="7.197916666666667in"
height="3.1145833333333335in"}

**Figure 6. Peak wind gusts during the November 21-22, 2006
nor'easter.**

After the pre-Thanksgiving nor'easter, conditions gradually began to dry
out, aided by a building ridge of high pressure over the southern U.S.
This high pressure area brought warm temperatures to the state November
27-30, when daily highs surged into the 70s over the interior sections.
Raleigh-Durham recorded a daily record high of 77 degrees for November
30.

Figures 7 and 8 depict the daily maximum and minimum temperatures
observed at Raleigh-Durham (RDU) and Greensboro (GSO) during November
2006. The dashed lines represent the normal maximum temperature (red)
and the normal minimum temperature (blue).

![](media/image7.wmf){width="5.375in" height="3.1979166666666665in"}

**Figure 7. Daily maximum and minimum temperatures observed during
November 2006**

**at Raleigh-Durham (RDU).**

![](media/image8.wmf){width="5.333333333333333in"
height="3.1979166666666665in"}

**Figure 8. Daily maximum and minimum temperatures observed during
November 2006**

**at Greensboro (GSO).**

**Current, Semi-Annual and Annual Temperature Trends**

The warmer than normal temperatures of November ended the two
consecutive months with below normal temperatures at Raleigh and
Greensboro. However, three of the past six months have been cooler than
normal at Raleigh, while only two of the past six months below normal at
Greensboro.

Figure 9 illustrates the monthly temperature departures from normal at
Raleigh-Durham and Greensboro. Eight of the past twelve months have been
warmer than normal at Raleigh-Durham. Nine of the past twelve months
have been warmer than normal at Greensboro. December 2005, May 2006,
September 2006, and October 2006 have been the only months in the past
year that averaged significantly cooler than the 30 year normal.

![](media/image9.wmf){width="5.59375in" height="3.59375in"}

**Figure 9. Monthly temperature departures from normal at Raleigh-Durham
and Greensboro from November 2005 through November 2006.**

**Current, Semi-Annual, and Annual Precipitation Trends**

The trend of above normal rainfall that began in the summer season,
continued through November throughout much of North Carolina. The 9.03
inches of rain recorded at Raleigh-Durham were well above normal. This
was the fifth time in the past six months that RDU has recorded above
normal rainfall. RDU had a yearly rainfall surplus of 4.62 inches on
September 30. This surplus had grown to 10.68 inches as of November 30.
Figure 10 depicts the precipitation trends at RDU during the past 12
months. The dry pattern the first half of 2006 was replaced by wet
conditions beginning in June.

The 5.95 inches of rain recorded at Greensboro was 2.99 inches above
normal for November. This was also the fifth month in the past six that
Greensboro has recorded above normal rainfall. Greensboro completed a
dramatic turn from a 7.50 inch rainfall deficit for 2006 at the start of
June, to an 8.55 inch 2006 rainfall surplus by November 30. Figure 11
depicts the monthly precipitation totals and the departure from normal
during the past 12 months at Greensboro. Note the huge surplus in
rainfall since June, after 5 consecutive very dry months.

![](media/image10.wmf){width="5.416666666666667in" height="3.3125in"}

**Figure 10. Semi-annual and annual precipitation trends at
Raleigh-Durham (RDU).**

![](media/image11.wmf){width="5.447916666666667in"
height="3.3645833333333335in"}

**Figure 11. Semi-annual and annual precipitation trends at Greensboro
(GSO).**

**North Carolina Water Resources Information and Outlook**

Due to the wet conditions that have been observed in the second half of
2006, drought was no longer a concern anywhere in North Carolina as the
end of the year approached. Many of the reservoirs that supply water to
major metropolitan areas of the Triad and Triangle regions topped full
pool levels by October 31. Many had to begin releasing water during
November, as the heavy rain events brought significant runoff.

For the latest information concerning the drought, visit
<http://www.ncwater.org/drought/>

**Climate Outlook for the winter 2006**

The Climate Prediction Center recently released the final winter
outlook. Details concerning this forecast can be found at the web
address below:

<http://www.cpc.ncep.noaa.gov/products/predictions/multi_season/13_seasonal_outlooks/color/page2.gif>

The headline for this winter season continued to be the comeback of El
Nino in recent months. Moderate El Nino conditions (sea surface
temperatures 0.5°- 1.0° Celsius warmer than normal) were observed in the
critical regions of the Equatorial Pacific as of the first week in
December. Confidence has increased that moderate El Nino conditions will
continue through the spring of 2007.

Recent research indicates that moderate to strong El Nino's typically
bring an enhanced chance of above median precipitation across the
southeastern U. S., including much of North Carolina during the winter
season. The temperature forecast for the winter season indicates that
temperatures should average near normal across the southeastern U.S.
including North Carolina. As is typically the case during the winter
season across North Carolina, there should be large variability in
temperatures from week to week. Some weeks will average above normal,
while others will be below normal. The temperature and precipitation
outlooks for the United States during the upcoming winter season can be
viewed in Figure 12.

You can keep up with latest monthly and seasonal forecasts by visiting
the Climate Prediction Center website at http://www.cpc.ncep.noaa.gov/.

![](media/image12.png){width="7.604166666666667in"
height="2.6041666666666665in"}

**Figure 12. The U.S. Temperature and Precipitation Outlooks from the
Climate Prediction Center for the winter of 2006-2007.**

**NC Weather Review Team**

Phillip Badgett

Michael Strickler