The Arctic Outbreak of 4-8 January 2014
by
Richard H. Grumm
National Weather Service State College, PA 16803
1. INTRODUCTION
An artic outbreak affected much of eastern North American to include the eastern United States
from 4-8 January 2014. The cold peaked on 6 January 2014 providing the coldest 24 hour period
over the United States in the 21st Century to date. Relative to previous 20th Century events, this
event was relatively tame and will likely rank near the 40th coldest day. It trails behind events
such as the Christmas Arctic outbreak of December 1983 and the December 1989 outbreak. The
most recent comparable, though colder arctic outbreaks occurred in January 1994 and 1996
respectively. The low temperatures observed in January 2014 did not come close to reaching the
-70F reading at Rogers Pass, Montana on 20 January 1954 or the Pennsylvania State record of 42F set at Smethport, PA on 5 January 1904.
The cold outbreak affected schools with reports of school closings due to wind chills, set or tied
low temperature records, and caused delays at airports from the Dakotas to the East Coast (AP
2014). The cold affected NFL playoff games and lead to rapid ice formation on the Great Lakes
which hampered shipping in Lake Erie. The outbreak brought the term “polar vortex” into the
mainstream media. Many locations set new daily low temperature records for the date some of
which went back 20 to 126 years 1.
This paper will document the pattern and compare it to several previous record events in the
eastern United States. In central Pennsylvania the cold episode of record was February 1899.
2. Methods and Data
The large scale pattern was reconstructed using the 00-hour forecast of the NCEP Global
Forecast System (GFS) as first guess at the verifying pattern. The standardized anomalies were
computed in Hart and Grumm (2001). All data were displayed using GrADS (Doty and Kinter
1995). The standardized anomalies and the probability distribution functions are based on the reanalysis climate (R-Climate). Though not shown here, they could be produced from internal
model system climatologies (M-Climate).
1
AP report Minneapolis hit -20 tying the record set back in 1888 and New York City tied broke a record set in 1986.
The traditional standardized anomalies were produced from the GFS 00-hour forecast using
Climate Forecast System based means and standard deviations. The climatology spans a 30 year
period.
3. PATTERN
The large scale pattern at 500 hPa (Fig. 1) over the United States in 24-hour increments from
0000 UTC 3 to 8 January 2014 show the “polar vortex” over southwestern Canada at 0000 UTC
5 January, a trough extending south of these feature was over Minnesota on 6 January which
then moved into the Great Lakes by 7 January before lifting back into Canada on the 8th.
The cold air at 850 hPa (Fig. 2) entered the northern Plains on 5 January and the -30C isotherm;
often associated with the crème de la crème of arctic air 2; was visible across northern Minnesota
and North Dakota. As the arctic air moved into the Midwest the standardized anomalies fell to
-3σ below normal. Ahead of the arctic air there was a brief surge of warm air over the eastern
United States (Fig. 2b-c) and the 850 hPa temperature anomalies peaked at over +2σ above
normal in New England. As the arctic air moved over the eastern United States, a -30C contour
was observed in the CFSR data as far east as western Pennsylvania (Fig. 2e). The air mass began
to lift to the northeast and it warmed considerably over the eastern United States by 0000 UTC 8
January 2013.
At the surface (Fig. 3) an area of high pressure with +2 to +3σ pressure anomalies was present in
the arctic air and a strong cyclone developed in the southern Plains (Fig. 3a) and moved up the
arctic front, across the Great Lakes and into northeastern Canada (Fig. 3b-f).
The impact of the 48 to 60 hour period of extreme cold caused rapid formation of ice on rivers
and produced ice on the Great Lakes. Lake Erie (Fig. 4); a relatively shallow lake; developed a
significant ice cover which was visible by satellite by 8 January and the 17150 UTC 9 January
visible satellite image clearly showed the extensive ice cover over Lake Erie’s and portions of
southern Huron, and Saginaw Bay, Michigan.
A list of the top 10 coldest dates in central Pennsylvania is provided in Table 1. Table 2 provides
a list of several of the colder periods based on COOP data. These data are used to reconstruct
several cold outbreaks from the past in the following section.
4. PAST EVENTS
The most recent eastern United States arctic episode occurred in January 1996 and January 1994.
The 850 hPa temperatures and anomalies during the January 1994 event are shown in Figure 5.
Like many historic arctic outbreaks, this event was accompanied by -30 to -36C air at 850 hPa.
The core of the cold air passed west and then south of the Great Lakes with -3s 850 hPa
2
Term and value used in the Albany MAP.
temperature anomalies. A contributing factor to the low temperatures associated with this event
in the Mid-Atlantic region was a deep snow cover which was not present during the 2014 event.
The core of the December 1983 arctic outbreak was associated with -30 to -36C air at 850 hPa
(Fig. 6). The largest thermal anomalies pushed farther west and south relative to the events of
2014 and 1994 with a larger pocket of -30C air and -4s temperature anomalies focused over the
Mid-Mississippi Valley (Fig. 6c).
January 1982 actually had 2 successive arctic outbreaks including 9-11 January (Fig. 7) and 1518 January 1982 (Fig. 8). The 15-18 January 1982 arctic outbreak had a -42C contour enter the
northern Plains (Fig. 8a) and northern New England (Fig. 8d). Over time a -32C contour came
over the southern Great Lakes. The earlier outbreak produced a rare -5σ 850 hPa temperature
anomaly over southern Illinois at 1200 UTC 10 January where 850 hPa temperatures of 34C
covered most of southern Illinois. Two historic events occurred during the cold period January
1982 including the 14 January 1982 Air Florida aircraft crashing into the icy Potomac River due
to icing and the frigid AFC Championship game in Cincinnati, Ohio on 10 January 1982.
Several other memorable arctic outbreaks include December 1989, which peaked around
Christmas in the eastern United States (Fig. 9). Though not shown, the 850 hPa temperature
anomalies were -6s below normal along the Gulf Coast at 0000 UTC 24 December 1989 and a
rare snow was observed in the southeastern United States on 24 December 1989. Another
remarkable aspect of December 1989 was that it was one of the coldest Decembers in the eastern
United States but after that arctic outbreak around Christmas, the pattern changed and most of
the eastern United States experienced warmer than normal conditions for the remainder of the
winter.
There was a brief arctic outbreak in the eastern United States on 24-25 December 1980 (Fig. 10)
which too was accompanied by -30C air at 850 hPa.
The coldest day in State College as 10 February 1899, The 20th Century Re-analysis data was
used to reconstruct the conditions during this cold episode. The 850 hPa temperatures during this
event indicated that the between -26 and -28C air moved over the region (Fig. 11) and that this
air mass to was accompanied by the polar vortex (Fig. 12). Several record low temperatures were
set in February 1899 at State College and the all-time low of -20F for the site was set on 10
February. The 850 hPa temperatures may not be representative due to the sparse data used to
reconstruct the vertical structure of the atmosphere.
The conditions in 1936 show the same pool of cold air (Fig. 13), though lacking a -30C contour
and a deep 500 hPa low (Fig. 14).
5. SUMMARY
The first significant arctic outbreak of the 21st Century affected much of the eastern United
States from 4-8 January 2014. For the first time in over a decade 850 hPa temperatures of -30C
spread over portions of the eastern United States plunging surface temperatures to near or below
previous record lows for the date. Many locations in the core of the arctic air struggled to get to
zero Fahrenheit. The cold caused massive closing of schools, froze rivers and streams, and
caused rapid formation and expansion of ice on portions the Great Lakes.
The pattern which produced the cold included a deep polar vortex which moved into eastern
North America and sub -30C air at 850 hPa, marker used to track some of the colder arctic air
masses in North America. Intrusions of -30C are relatively rare and intrusions of the even rarer
-40C are extremely rare. This event clearly saw a deep penetration of -30C air into the eastern
United States.
Several 20th Century arctic outbreaks were presented. Nearly all which were observed since 1979
were associated with -30C or lower 850 hPa temperatures. Events of this nature have dropped off
considerably since the mid-1990s and the arctic outbreak of 1994 was one of the last significant
outbreaks in recent memory. The outbreak of December 1983 was one of the more significant
outbreaks in recent history.
The 20th Century re-analysis data was used to examine some other historical cold outbreaks.
These events too were associated with -26 to -28C air at 850 hPa and a deep 500 hPa cyclone or
polar vortex. The 1899 and 1934 (Table 1) cold outbreaks are unique in that these are record low
temperatures observed in February. Most of the coldest 50 record lows are typically set in late
December through January. Several years with record lows in the top 20 were set in February to
include 1899, 1934, 1912, 1905, 1979, 1917, 1918, and 1936. The largest outlier was 18 March
1900 when a low of -9F was recorded. The 20th Century re-analysis data should be used with
caution. There was no upper air network until after World War II and satellite observations
lagged by another 3 decades. The more modern data sets have more robust data. There may
have been some -30C air at 850 hPa in these pre-1948 cases that cannot be reconstructed.
Setting record low temperatures at the surface is a complex issue relate to more than the polar
vortex and the temperatures at 850 hPa. Snow cover, wind, and antecedent conditions can and do
play a significant role in low temperatures and record low temperatures during the winter. For
example, the second coldest low temperature in State College occurred in January 1994. In
addition to the extremely cold air mass and ideal pattern, a deep snow cover was present and a
deep snow cover was present to the north and west. Snow cover and light winds can produce
ideal conditions for radiational cooling. This simplistic study did not investigate or try to isolate
events were radiational cooling and cover may have contributed to the record low temperatures.
The lack of arctic air in recent years likely has made people unaccustomed to it. There is an
acclimation process associated with dealing with cold and extreme cold. If arctic outbreaks
continue to become less common, our ability to cope with them will only diminish.
Arctic outbreaks have become less frequent as shown in the Tables 1 & 2. The relationship to
global warming was not addressed here. However, research and climate simulations suggest that
periodic outbreaks of cold will persist through most of the 21st Century (KodrA et al 2011).
6. Acknowledgements
The Albany map for observations and discussions on the storm, storm potential, and snow to
liquid issues related to the storm. Greg Carbin, John LaCorte and Charles Ross for climate
records and dates.
7. References
Doty, B. E., and J. L. Kinter III, 1995: Geophysical data and visualization using GrADS.
Visualization Techniques Space and Atmospheric Sciences, E. P. Szuszczewicz and
Bredekamp, Eds., NASA, 209–219.
Compo, G.P., J.S. Whitaker, P.D. Sardeshmukh, N. Matsui, R.J. Allan, X. Yin, B.E.
Gleason, R.S. Vose, G. Rutledge, P. Bessemoulin, S. Brannimann, M. Brunet, R.I.
Crouthamel, A.N. Grant, P.Y. Groisman, P.D. Jones, M. Kruk, A.C. Kruger, G.J. Marshall,
M. Maugeri, H.Y. Mok, . Nordli, T.F. Ross, R.M. Trigo, X.L. Wang, S.D. Woodruff, and
S.J. Worley, 2011: The Twentieth Century Reanalysis Project. Quarterly J. Roy. Meteorol.
Soc., 137, 1-28.
Compo, G.P., J.S. Whitaker, and P.D. Sardeshmukh, 2006: Feasibility of a 100 year
reanalysis using only surface pressure data. Bull. Amer. Met. Soc., 87, 175-190.
Grumm, R.H. and R. Hart. 2001: Standardized Anomalies Applied to Significant Cold
Season Weather Events: Preliminary Findings. Wea. and Fore., 16,736–754.
Hart, R. E., and R. H. Grumm, 2001: Using normalized climatological anomalies to rank
synoptic scale events objectively. Mon. Wea. Rev., 129, 2426–2442.
Kocin, P. J., and L. W. Uccellini, 2004: Northeast Snowstorms, Volume I: Overview. Meteor.
Monogr., Vol. 32, No. 54, Amer. Meteor. Soc., 1-296.
Kocin, P. J., and L. W. Uccellini, 1990: Snowstorms along the northeastern Coast of the United
States: 1955 to 1985. Meteor. Monogr., No. 44, Amer. Meteor. Soc., 280p.
Kodra, E, K. Steinhueuser, and A.R. Ganguly: 2011: Persisting cold extremes under 21st
Century warming scenarios. Geo. Res. Letters,38,8.
Stuart,N.A and R.H . Grumm 2006: Using Wind Anomalies to Forecast East Coast Winter
Storms. Wea. and Forecasting, 21,952-968.
http://eyewall.met.psu.edu/rich/cases/06Jan2014/patterns/US-hgtprs50000Z08JAN2014.png
Figure 1. Return to text.
Figure 2. As in Figure 1 except for 850 hPa temperatures and anomalies in 12-hour increments from a) 1200 UTC 5 January through f) 0000 UTC 8
January 2014. Return to text.
Figure 3. As in Figure 2 except for CFSR mean sea-level pressure and pressure anomalies. Return to text.
Figure 4. GOES visual image valid at 1715 UTC 9 January 2014 showing ice over Lake Erie, near shore ice in southeastern lake Huron, and ice in Saginaw Bay,
Michigan. The yellow arrows show these three areas. Clouds were present over the center of Lake Huron and the shore ice was identified using loops of
imagery. Inset show MODIS ice view in southern Pennsylvania along the Susquehanna river. Return to text.
Figure 5. As in Figure 3 except for 850 hPa temperatures from 1200 UTC 14 through 0000 UTC 17 January 1994. Return to text.
Figure 6. As in Figure 5 except for 850 hPa temperatures from 12 23 December to 0000 UTC 26 December 1983. Return to text.
Figure 7. As in Figure 6 except for the successive 24 hour periods of 1200 UTC 8 to 13 January 1982. Return to text.
Figure 8. As in Figure 6 except for the 6 hour periods of 1200 UTC 16 January through 18 January 1982. Return to text.
Figure 9. As in Figure 6 except for the 25 hour periods of 1200 UTC 24 December through 1200 UTC 29 December 1989. Return to text.
Figure 10. As in Figure 6 except for the 24 hour periods of 1200 UTC 24 through 29 December 1980. Return to text.
th
Figure 11. The 20 Century reanalysis data showing 850 hPa temperatures (C ) and temperature anomalies in 12 hour increments from a) 0000 UTC 7
February 1899 through i) 0000 UTC 11 February 1899. Return to text.
Figure 12. As in Figure 11 except for the 500 hPa heights and height anomalies. Return to text.
Figure 13. As in Figure 11 except for the period of 0000 UTC 22 through 26 January 1936. Return to text.
Figure 14. As in Figure 13 except for 500 hPa heights. Return to text.
Rank
Temperature
Date
1
-20
2/10/1899
2
-18
1/20/1994
3
-17
1/21/1985
4
-17
1/18/1982
5
-17
2/9/1934
6
-17
1/14/1912
7
-16
1/25/1963
8
-16
2/11/1899
9
-15
1/22/1985
10
-15
1/24/1963
11
-15
1/14/1914
12
-15
1/5/1904
13
-14
1/23/1936
Table 1. List of the coldest low temperatures in State College
based on COOP site data. Return to text.
Date
23-25 December 1983
22-24 December 1989
18-20 January 1996
9-10 January 1984
31 December 1973-1 January
1974
8-11 February 1899
11-12 January 1994
Table 2. List of some of the
coldest periods in the eastern
United States based on COOP
data. Return to text.