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TRANSCRIPT
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Hurricane Sandy: An Eastern United States Superstorm by
Richard H. Grumm
National Weather Service State College, PA 16803
Contributions by Craig Evanego
Abstract
Hurricane Sandy was an enduring (22-30 October 2012) late season tropical cyclone which developed
during a period of blocking over the Atlantic Basin. The North Atlantic Oscillation was near -2 during the
evolution of Sandy. As Sandy moved north, it interacted with mid-latitude short-wave which caused the
storm to move rapidly to the west on 29 October. The interaction with the strong mid-latitude short-wave
caused Sandy to change and produced one of the deepest low pressures ever recorded along the Eastern
seaboard.
The minimum central pressure was estimated at 940 hPa (27.76 in) and its diameter at times
exceed 1000km making it one of the largest Atlantic hurricanes on record. The storm came
ashore about 5 miles southwest of Atlantic City, New Jersey around 8 PM 29 October 2012.
The strong easterly winds and long easterly fetch of the storm produced a storm surge and large
waves which had devastating effects on the coastal regions from Cape Cod to the Chesapeake.
Historic flooding was observed on Long Island, coastal New Jersey, and in New York City.
In coastal regions, the wind and waves will long be remembered. Winds over 80 mph were
common for several hours over Long Island. The strong winds produced massive power outages
in the Mid-Atlantic region.
Rainfall with the storm was heaviest in the Mid-Atlantic region and caused flooding issues. The
upper-level system and cold air produced historic snowfall in the Appalachian Mountains from
eastern Tennessee into southwestern Pennsylvania. Superstorm Sandy broke records for October
snowfall, winds, waves, and tidal surges. The lasting effects will likely be the damage caused by
the wind driven waters of the Atlantic.
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1. Overview
Tropical storm Sandy moved up the East Coast of the United States on 28-30 October 2012 (Fig.
1). As the storm moved up the coast, it interacted with a strong short-wave in the westerlies. The
resulting interactions produced a deep cyclone and strong winds north of the cyclone center. The
resulting impacts of the storm included strong and damaging winds, record storm surges into
Long Island, New York City and New Jersey, heavy rainfall in the Mid-Atlantic, and historic
snowfall in the higher elevations of the Appalachians from North Carolina into southwestern
Pennsylvania.
Tropical storm Sandy began as a tropical wave over the Caribbean Sea around 19 October 2012.
The NCEP GFS 00-hour forecasts show the evolution of the surface system from 1200 UTC 22-
27 October 2012 (Fig. 1). The initially Sandy had no closed isobars but represented a -5
pressure anomaly in the Caribbean (Fig. 1a) and quickly gained a close circulation and was a -8s
cyclone (Fig. 1b) which quickly turned to the north and was off the coast of Florida by 1200
UTC 27 October 2012 (Fig. 1f). The 12 hourly RAP analysis shows Sandy moving up the East
Coast from 1200 UTC 27 through 0000 UTC 30 October 2012 shows to include the dramatic
turn to the northwest after 1200 UTC 29 October 2012 (Fig. 2e) which brought Sandy into New
Jersey by 0000 UTC 30 October 2012 (Fig. 2e). The 1-hourly RAP (Fig. 3) data shows the
Sandy’s rapid approach to southern New Jersey and the rapid movement across New Jersey.
Over the course of the life cycle of Sandy, then North Atlantic Oscillation (NAO) was strong
negative, around -2 during most of the period of late October 2012. A negative NAO is often
associated with blocking in the North Atlantic and is period when the global models often
perform slightly better than normal1. The 500 hPa pattern from 1200 UTC 25 through 1200 UTC
30 October 2012 (Fig. 4) showed a strong high latitude ridge which peaked on 29 October 2012.
The 500 hPa trough associated with Sandy and the 500 hPa trough moving to the southeast out of
North America merged becoming a deep trough (Fig. 4f) on the western flank of the blocking
high latitude 500 hPa ridge (Colucci 2001) over the Labrador Sea. The 500 hPa pattern and
anomalies show a distinct omega block over the Atlantic basin on 29-30 October 2012 (Figs. 4e-
f) which developed from a Rex block (Rex 1950a;Rex 1950b) which was evident from 25-28
October 2012.
This paper will document the conditions and some of the high impact weather associated with
tropical cyclone Sandy and its interaction with a mid-latitude short-wave and downstream
blocking. The focus is on how the standardized anomalies facilitated accessing the intensity of
1 Based on research by Ryan Maue looking at 500 hPa correlations.
2 During the forecast phase we changed the anomalies displayed which were limited to 6 to -6 standard deviations
to account for the incredible range that were present in the forecasts to accommodate and show these historic
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this storm and the pattern it developed into relative other historical high impact storms. The
storms impacts are based on new accounts and datasets that show the heavy rainfall, high winds,
and heavy snowfall associated with the storm.
2. Data and Methods
The NCEP Global Forecast System (GFS) and the Rapid Update Cycle (RAP) were used
to reconstruct the pattern associated with tropical cyclone Sandy. These data were compared to
the 30-year climate as described in Hart and Grumm (2001). The standardized anomalies aid in
identifying regions were key fields, such as 500 hPa heights, precipitable water (PWAT), and
mean sea-level pressure depart significantly from normal. Shading in most images reflects the
standardized anomalies. All model and standardized anomaly data were plotted using GrADS
(Doty and Kinter 1995).
This technique was applied to the NCEP/NCAR reanalysis data which is on a 2.5x2.5
degree grid (Kalnay 1996) to compare Sandy to previous historic storms. Post 1979 cases were
examined and displayed using the Climate Forecast System Version I data on a 0.5x0.5 degree
grid (Saha et al. 2006;Saha et al. 2010).
The Stage-IV quantitative precipitation estimates (QPE) data where obtained in 6-hour
increments to examine 6 to 72 hour rainfall. These data were displayed using GrADS (Doty and
Kinter 1995).
Wind, snow, and tidal data were obtained from news sources and National Weather
Service public information statements. These data were plotted in ArcView.
3. The pattern and standardized anomalies
The 500 hPa pattern (Fig. 4) showed the evolution of a blocking episode over the North Atlantic.
By 29 October an Omega block was present over the North Atlantic (Fig. 4e). The 500 hPa
trough over North America which merged with Sandy produced a deep trough over the eastern
United States with -4 to -5 height anomalies in the southeastern United States.
The cold air associated with the mid-latitudinal trough (Fig. 5) showed 850 hPa temperatures in
the 0 to -4C range. The -4C air over West Virginia and the central Appalachians represented a -2
to -3 event, implying unseasonably cold air over the region where the heavy snow was
observed (Fig. 6). Due to the blocking over the North Atlantic, as the surface cyclone moved
westward (Figs. 2&3) the warm air north of the cyclone center moved into New England and
southern Canada. Reminiscent of several historic storms such as the 25-26 November 1950 and
26 January 1978 Cleveland Superbomb (Hakim et al 1995), snow and cold air were observed
well south of significantly warmer air and rain.
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The surge of moisture, as indicated by the PW and precipitable water anomalies (Fig 7) showed
PW values over 65mm near the cyclone central between 29/0600 and 29/1800 UTC. The PW
anomalies were on the order of -4 to -5 above normal near and north of the cyclone center. The
high PW air move into southern New Jersey with Sandy and the PW values weakened rapidly as
the storm moved inland (Fig. 7d-f). The heaviest rainfall (Fig. 8) fell in close proximity, though
slightly to the south and west of the surge of high PW air. The RAP PW in hourly increments
showed the same general pattern and evolution as the GFS (Fig. 8) with a surge of high PW air
into New England and a surge of high PW air with the cyclonic circulation associated with
Sandy (Fig. 3) moving across New Jersey. Similar to the GFS, the PW values and anomalies fell
rapidly as Sandy moved into New Jersey.
The prolonged strong easterly flow along the East Coast from 27-29 October (not shown)
combined with the enhanced flow from 29/0000 UTC through 30/0000 UTC (Fig. 9) allowed
water to pile up along the coast from the Carolinas into southern New England. By 29/0000 UTC
the 850 hPa winds were over 40kts with 1 to 3 above normal winds into the coast line (Fig. 9a).
By 29/1200 UTC winds over 50kts impacted the coastal regions from Long Island to Maryland
and were -4 to -5 above normal. The strongest winds, with total 850 hPa wind anomalies in the
+6 to +8 range impacted Long Island and New Jersey (Fig. 9d-e) before becoming strong
southerly flow after. The hourly RAP data shows the strongest winds coming onshore at
29/0000 UTC over New Jersey and Long Island (Fig. 10a). The 850 hPa winds peaked near
100kts along the Jersey shore and over eastern most Long Island. The large wind anomalies were
associated with the New Jersey 90-100kt winds where the anomalies were on the order of -8
above normal. These strong winds moved inland (Fig. 10b) and weakened. The 850 hPa low
came ashore around 30/0000 UTC (Fig. 10e). These data suggest the winds over Long Island and
New York City veered from about 040 to 120 degrees in the 6 hour period from 29/0000 through
30/0100 UTC and the winds were +5 to +7 above normal during the entire 6 hour period.
4. High impact weather
Superstorm Sandy will be long remembered for the high impact weather along the East Coast to
include the extensive damage due to coastal flooding. In New York City a record storm surge of
13.88 feet (NY Times 2012; Table 2) was recorded at the Battery. The strong winds produced
massive power outages as wind gusts from southern New England to Delaware reached 50 to 89
mph. The strongest winds were observed over Long Island and coastal New Jersey (Fig. 11).
Plots of power outages imply western Connecticut, Long Island, New York City, southern New
York State, and easternmost Pennsylvania were hardest hit by strong winds and downed power
lines. New reports suggest power outages were reported in 17 States due to the winds associated
with Sandy and the mid-latitude trough. Power outages in West Virginia were attributed to heavy
wet snow downing trees on power lines.
The strong easterly winds and surge of high PW air produced heavy rainfall (Fig. 8) across the
Mid-Atlantic region. Rainfall of over 50 mm (2 inches) was observed from New Jersey
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westwards into western New York and Ohio. The heaviest rainfall, over 100 mm (4 inches)
covered most of southern Pennsylvania, Maryland eastward to southern New Jersey and the
Delmarva. Areas of Maryland saw in excess of 250 mm (10 inches) of rainfall. The heavy rains
produced flooding and some river flooding over the regions that received 100 to 250 mm of
rainfall.
In the cold air, beneath the upper-level closed low with 850 hPa temperatures in the -2 to -4C
range, heavy snow (Fig. 6) was observed. The heavy wet snow caused power outages in West
Virginia.
5. Forecasts
i. Deterministic forecasts
The forecasts of mean sea-level pressure and the mean sea level pressure anomalies for the EC
are shown in Figs 12 & 13. The longer range forecasts from 21 to 28 October used on the 1200
UTC forecast cycles. The EC “verification” is the Fig. 13a. All forecasts are valid at 0000 UTC
30 October 2012 close to the time of landfall. The longer ranges forecasts (Fig. 12f) showed
some timing issues but the forecasts initialized at 22/0000 UTC (not shown) began to converge
to the extremely deep cyclone along the East Coast. The forecasts issued after 26/0000 UTC
(Fig. 13) were clearly very consistent forecasts of a cyclone coming ashore with -8 pressure
anomalies in the Mid-Atlantic region, near New Jersey or Delaware. There were however some
timing issues as the when the storm would come ashore. The storm and forecasts of the storms
landfall varied markedly.
Comparable GFS forecasts are shown in Figures 14 & 15. Nine GFS forecasts valid at 30/0000
UTC are shown. The forecast initialized at 23/0000 UTC did not bring Sandy onshore and the
forecast initialized at 24/1200 UTC brought Sandy into the Gulf of Maine at 0000 UTC 31
October. The 25/1200 UTC forecast brought the storm into Long Island. Forecast initialized after
25/1200 UTC provided excellent guidance as to the storms westward track and inland
progression somewhere in the region between New York City and Delaware Bay. No GFS
forecast prior to 22 October are shown due to limited data.
The shorter range forecasts (Fig. 15), zoomed into the Mid-Atlantic region, and showed a similar
trend of being behind the EC in bringing the system onshore. Forecasts issued on or after
27/1200 UTC were comparable in the 27.5km GFS and 16km EC.
j. ensemble forecasts
The ensemble forecasts from both the EC and GFS showed the potential for Sandy to make a
hard turn to the left. The timing and intensity of the cyclone varied considerably thus, the
ensemble mean forecasts initially did not show as deep a cyclone as the deterministic models.
The averaging process obfuscated the potential depth of the cyclone, though this process
indicated the potential uncertainty in these forecasts.
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EC mean-sea level pressure forecasts from 6 cycles are shown in Figures 16 & 17. The upper
panels show the ensemble mean and with standardized anomalies. The lower panels show the
spread about the mean. In the mean, the longer range forecasts all show a weaker cyclone center
farther off the coast at 30/0000 UTC. Timing and intensity issues played a critical role in the
uncertainty and generally weaker cyclone in the ensemble mean. The 23/1200 UTC run showed
a convergence of solutions with the cyclone at -4s below normal near the New York Byte (Fig.
16c&f). The forecasts initialized at 24/0000 UTC (Fig. 17c&f) clearly showed a stronger mean
cyclone and decreasing uncertainty. The mean pressure was -4 to -5s below normal implying a
useful forecast of the potential of the high impact storm at least 6 days prior to landfall.
Though initially weaker with the surface cyclone and farther east, the NCEP GEFS also showed
the potential for a strong cyclone with intensity and timing issues (Fig. 18, 19, 20). The spread
about the mean in Figure 18f clearly shows this effect. Several GEFS members had the faster
solution over the Great Lakes while other solutions kept the cyclone over the western Atlantic at
30/0000 UTC. This lead to a weaker cyclone over the western Atlantic and only -3s below
normal MSLP anomalies (Fig. 18c) but a dipole pattern in the spread about the mean (Fig. 18f).
Dipole spread patterns are often a good means to visualize intensity and timing issues.
Shorter range GEFS forecast of the cyclone showed stronger anomalies as the uncertainty
diminished (Fig. 19). Timing differences are still evident in these forecasts, but the dipole effect
in the spread about the mean diminished rapidly between forecasts issued at 26/1200 and
27/1200 UTC (Figs. 19d-f). Not surprisingly, as these forecasts converged toward the depth and
location of the cyclone, the pressure anomalies in the cyclone center began to trend toward the
large anomalies in the deterministic models. Note the -6 to 7s pressure anomalies in the GEFS
forecasts from the 27/1200 UTC forecast cycle.
The impact of the timing and track issues had a significant impact on the quantitative
precipitation forecasts (QPF) and wind forecasts, though only QPFs are addressed herein. Earlier
forecasts had a more northern track, which produced a higher probability of 100mm or more
QPF farther north (Fig. 21). As the track shifted to the south and west, the threat of the heavy
rainfall shifted to the south and west (Fig. 22). These shifting forecasts had significant impact on
both flood and flash flood forecasts. Despite the relatively good forecasts of the deep cyclone
and massive area to be affected by strong winds, the details as to where the strongest winds and
heavier rain would fall were difficult to predict.
6. Summary
The high latitude blocking and negative NAO likely were contributing factors to both the
relatively high predictability of the event and the track of the system. Without the block over the
North Atlantic, Sandy may have continued on a more easterly track and thus avoiding the East
Coast of the United States.
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The estimated pressure at landfall was 940 hPa which compares to the 948 hPa estimate of the
1938 Long Island Express. Low pressure of other significant storms is listed in Table 1.
The GFS forecasts were about 1.5 days slower than the EC in turning the surface cyclone toward
the west
Coastal regions of Long Island and southern New England (Fig. 10) experienced at least a 6 hour
period where the 850 hPa winds were in excess of 90kt and the 850 hPa wind anomalies exceed
+5 above normal. The prolonged strong easterly flow combined with this 6-hour period of
extremely high winds likely contributed to the surge of sea water and the high surf which
wreaked havoc from Greenport, New York to New York City on the Long Island Sound and
from Montauk to Staten Island on the Ocean side of Long Island. Similarly strong winds from
the east and northeast battered the coastal regions of New Jersey. The sustained strong winds
produced record storm surges. The Battery in NYC reached 13.88 (Table 2).
Colle et al (2010) examined storms which produced storm surges in New York City. They listed
all storms which produced storms which produced significant surges above the mean-high water
mark (Colle et al. 2010: Table 1) separating out tropical cyclones (Table2: Colle et al. 2010). The
top 3 storms were Hurricane Gloria September 1985 (2.0m), Hurricane Donna September 1960
(1.73m), and the nor’easter of 12-13 December 1992 (1.75m). A total of 17 tropical storms
produced strong storm surges. The list of extratropical cyclones includes many memorable East
Coast Winter Storms (ECWS) and famous nor’easters including the 31 October 1991 (1.40m),
13 March 1993 “Superstorm” (1.46m), and the 7-8 January 1996 “Blizzard of 1996” (1.35m) and
the 14-15 November 1995 nor’easter (1.24). Storm surges and coastal flooding are often
overlooked but important aspect nor’easters. The storm of 13-14 March produced a surge of 1.28
m.
Forecasts of the storm indicated that there was some modicum of predictability at least 5-8 days
in advance. There was considerable variability with the intensity and the timing of when the
strong winds and rain would impact the coastal regions. Thus, there were good forecasts
indicating the potential for Sandy to impact the Mid-Atlantic region and southern New England,
but the timing and location issues remained highly uncertain. These shifting forecasts had
significant impact on both flood and flash flood forecasts. Despite the relatively good forecasts
of the deep cyclone and massive area to be affected by strong winds, the details as to where the
strongest winds and heavier rain would fall were difficult to predict. The massive area covered
by the strong winds and extremely anomalous easterly winds likely lead to relatively successful
forecasts of damaging surf and tides.
The standardized anomalies in this case were extremely useful in aiding forecasters in
identifying a potentially historic storm. The GFS, EC and the accompanying EFS all showed a
deep cyclone with -6 to 9 pressure anomalies. The wind forecasts from all of these systems
showed the potential for 850 hPa and 925 hPa winds to be -6 to 8 above normal wind
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anomalies2. This historic case demonstrated the value of using standardized anomalies in the
forecast process and the need for forecasters to have access to standardized anomalies when
forecasting potential high impact and historically significant weather events. In addition to
climate derived standardized anomalies, internal model and ensemble probability distributions
need to be leverage to better aid in identifying HIWE events. These data would clearly lead to
ensemble based bots (Steiner 2012) which could alert users to high impact and extreme
weather events.
The forecasts presented here focused on the EC and GFS and the EFS based on these two
modeling systems. It should be noted that the NCEP SREF provided extremely useful guidance
related to landfall, impacts, and timing associated with Superstorm Sandy. These data were not
included here but will be included in a follow-on document.
7. Acknowledgements
Thanks to the EC TIGGE site for access to EC model, control and perturbation data. Thanks to
the NWS NOMADS site of GFS data. All CFS and NCEP/NCAR data are from UCAR data site.
NCEP produced the CFSR 30 year climate used. Al Cope (NWS-KIDX), Jeffery Tongue (NWS-
KOKX) and Steve Zubrick (NWS-KLWX) provided links and information related to storm
impacts and issues.
8. References
Bodner, M. J., N. W. Junker, R. H. Grumm, and R. S. Schumacher, 2011: Comparison of
atmospheric circulation patterns during the 2008 and 1993 historic Midwest floods.
Natl. Wea. Dig., 35, 103-119.
Changnon S.A and J.M. Changnon 1992: Storm Catastrophes in the United States: Natural
Hazards, 6, 2, 93-107. DOI: 10.1007/BF00124618.
Colle, B.A., K. Rojowsky, and F. Buonaiuto, 2010: New York City Storm Surges: Climatology and an
Analysis of the Wind and Cyclone Evolution. J.Appl. Meteor. Climatol., 49, 85-100
2 During the forecast phase we changed the anomalies displayed which were limited to 6 to -6 standard deviations
to account for the incredible range that were present in the forecasts to accommodate and show these historic values.
Date Low Pressure (hPa) Location Other Information
3 March 1914 961 New York
7 March 1932 955 Nantucket
21 September 1938 946 Bellport NY Long Island Express
28 March 1984 965 Eastern DelMarva Gyakum and Barker
1988.
14 March 1993 962 White Plains NY Super Storm
30 October 2012 940 Southern NJ Superstorm Sandy
Table 1. Record low pressures for cyclone along the East Coast. Courtesy Anton Seimon and
NHC.
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Colucci, S.J., 2001: Planetary-Scale Preconditioning for the Onset of Blocking. J. Atmos. Sci., 58,
933-942.
Doty, B.E. and J.L. Kinter III, 1995: Geophysical Data Analysis and Visualization using GrADS.
Visualization Techniques in Space and Atmospheric Sciences, eds. E.P. Szuszczewicz and J.H.
Bredekamp, NASA, Washington, D.C., 209-219.
Graham, Randall A., and Richard H. Grumm, 2010: Utilizing Normalized Anomalies to Assess
Synoptic-Scale Weather Events in the Western United States. Wea. Forecasting, 25, 428-
445
Grumm, R.H. 2011: New England Record Maker rain event of 29-30 March 2010.
NWA,Electronic Journal of Operational Meteorology,EJ4.
Grumm, R.H., and R. Hart, 2001a: Anticipating Heavy Rainfall: Forecast Aspects. Preprints,
Symposium on Precipitation Extremes, Albuquerque, NM, Amer. Meteor. Soc., 66-
70.
Grumm, R.H. and R. Hart. 2001b: Standardized Anomalies Applied to Significant Cold Season
Weather Events: Preliminary Findings. Wea. and Fore., 16,736–754.
Gyakum, JR , and E. S. Barker, 1988: A case study of explosive sub-synoptic scale cyclogenesis.
Mon. Wea. Rev.,116, 2225–2253.
Hakim, G. J., L. F. Bosart, and D. Keyser, 1995: The Ohio Valley wave-merger cyclogenesis event of
25–26 January 1978. Part I: Multiscale case study. Mon. Wea. Rev, 123:2663–2692
Hart, R. E., and R. H. Grumm, 2001: Using normalized climatological anomalies to rank synoptic
scale events objectively. Mon. Wea. Rev., 129, 2426–2442.
Junker, N.W, M.J.Brennan, F. Pereira,M.J.Bodner,and R.H. Grumm, 2009:Assessing the Potential
for Rare Precipitation Events with Standardized Anomalies and Ensemble Guidance at the
Hydrometeorological Prediction Center. Bulletin of the American Meteorological
Society,4 Article: pp. 445–453.
Kalnay, E., and Coauthors, 1996: The ncep/ncar 40-year reanalysis project. Bull. Amer. Meteor.
Soc., 77, 437–471.
Ludlum, D. M., 1956: "The Great Atlantic Low". Weatherwise, 9, 64-65.
Knox, J.L., 1955: The Storm "Hazel", synoptic resume of its development as it approached Southern
Ontario. Bull. Am. Meteor. Soc., 36, 239-246.
New York Times, 2012: Experts: NYC sea barrier could have stopped surge. And similar stories,1
November 2012.
Rex, D. F., 1950a: Blocking action in the middle troposphere and its effect upon regional climate. I. An aerological study of blocking action. Tellus, 2, 196–211.
——, 1950b: Blocking action in the middle troposphere and its effect upon regional climate. II. The climatology of blocking action. Tellus, 2, 275–301
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Saha, S., and Coauthors, 2006: The ncep climate forecast system. J. Climate, 19, 3483–3517.
Saha, Suranjana, et. al., 2010: The NCEP Climate Forecast System Reanalysis. Bull. Amer. Meteor. Soc.,
BAMS,1015-1057.
Steiner, C. 2012: Automate this: How algorithms came to rule our world. Portfolio Publisher, Penguin
Group.256p.
Stuart, N. and R. Grumm 2009, "The Use of Ensemble and Anomaly Data to Anticipate Extreme Flood
Events in the Northeastern United States",NWA Digest,33, 185-202.
Van Den Dool, H.M. 1994: Searching for analogues, how long must we wait. Tellus, 46A,314-324.
Power Outages
Company Location Outages
PSE&G New Jersey 1267424
Jersey Central Power & Light New Jersey 926,599
Long Island Power Authority Long Island 832,720
Consolidated Edison New York City 730,280
Table 3. Power outages for the more significantly affected utilities. The numbers
do not reflect the maxim number at the height of the storms impact. From the NY
Times web site.
Town State Min Pressure
record hPa
Date
Harrisburg PA 969.2 3 Jan 1913
Philadelphia PA 962.8 13 Mar 1993
Wilkes-Barre
Scranton
PA 972.6 25 Feb 1965
Baltimore MD 965.9 13 Mar 1993
Washington DC 966.5 13 Mar 1993
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Location Max Water
Level Astronomical
Tide Storm Surge Time EDST
Freeport 10.12 2.27 7.85 930pm
Reynolds Channel 10.1 2.32 7.78 906pm
Lindenhurst 7.73 1.47 6.26 1006pm
East Rockaway 10.8 2.72 8.08 842pm
Jamaica 11.65 3.28 8.37 936pm
Rockaway 11.75 2.81 8.94 924pm
Bergen Point 14.6 5.15 9.45 924pm
Battery 13.88 4.65 9.23 924pm
Kings Point 14.38 5.6 8.78 1000pm
Bridgeport 13.26 5.31 7.95 1006pm
New Haven 12.3 3.97 8.33 930pm
New London 8.04 2.08 5.96 812pm
Montauk 7.12 1.88 5.24 812pm
Sandy Hook 13.31 4.67 8.64 Atlantic City 8.9 4.08 4.82
Cape May 8.91 5.4 3.51 Lewes 8.71 4.85 3.86
Reedy Point 9.1 4.04 5.06 Philadelphia 10.62 5.26 5.36
Cambridge 4.55 2.08 2.47 Tolchester Beach 4.79 1.35 3.44
Table 2: Maximum water levels due to tides and storm surges based on gaged data. Return to text.
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Figure 2. As in Figure 1 except for the RAP analysis of pressure (hPa) and pressure anomalies in 12-hour increments from a) 1200 UTC 27 October through 0000 UTC 30 October 2012. Return to text.
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Figure 3. As in Figure 2 except for zoomed in over New Jersey and showing RAP every hour from a) 2100 UTC 29 October through f) 0200 UTC 30 October 2012. Return to text.
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Figure 4. As in Figure 1 except for GFS 500 hPa heights (m) and 500 hPa height anomalies in 24-hour increments from a) 1200 UTC 23 to f) 1200 UTC 28 October 2012. Return to text.
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Figure 5. As in Figure 4 except for 850 hPa temperatures ( C) and temperature anomalies from a) 0000 UTC 30 October 2012 through f) 0600 UTC 31 October 2012. Return to text.
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Figure 6. Snowfall (inches) from National Weather Service Public information statements. These data reflect higher amounts and do not show the full extent of the snowfall. The largest amounts, 33 inches was in southern West Virginia. Return to text.
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Figure 7. As in Figure 5 except for precipitable water (mm) and precipitable water anomalies from a) 0000 UTC 29 October through f) 0600 UTC 30 October 2012. Return to text.
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Figure 8. Stage-IV precipitation estimates (mm) from 0000 UTC 27 October through 1800 UTC 30 October 2012. Return to text.
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Figure 9. As in Figure 3 except for 850 hPa winds (kts) and 850 hPa total wind anomalies from a) 0000 UTC 29 October through f) 0600 UTC 30 October 2012. Return to text.
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Figure 10. As in Figure 9 except for RAP 850 hPa winds and anomalies in 1-hourly increments from a) 2000 UTC 29 October 2012 through f) 0100UTC 30 October 2012. Return to text.
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Figure 11. NWS public information statement data showing peak wind gusts in mph. Data still being processed and title will be fixed. Return to text.
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Figure 12. European Center (EC) global model forecasts of mean sea-level pressure valid at 0000 UTC 30 October 2012 from forecasts initialized at a) 1200 UTC 26 October 2012, b) 1200 UTC 25 October 2012, c) 1200 UTC 24 October 2012, d) 1200 UTC 23 October 2012, e) 1200 UTC 22 October 2012, f) 1200 UTC 21 October 2012. Return to text.
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Figure 13. As in Figure 12 except EC forecasts initialized at a) 0000 UTC 30 October 2012, b) 1200 UTC 29 October 2012, c) 0000 UTC 29 October 2012, d) 1200 UTC 28 October 2012, e) 1200 UTC 27 October 2012, f) 1200 UTC 26 October 2012. Return to text.
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Figure 14. NCEP GFS mean sea-level pressure forecasts valid at 0000 UTC 30 October 2012 from successive forecasts initialized at a) 0000 UTC 30 October, b) 1200 UTC 29 October, c) 0000 UTC 29 October, d) 1200 UTC 28 October, e) 1200 UTC 27 October, f) 1200 UTC 26 October, g) 1200 25 October, h) 1200 UTC 24 October, i) 1200 23 October. Return to text.
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Figure 15. As in Figure 13 except for NCEP GFS. Return to text.
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Figure 16. The European Center (EC) ensemble forecast system showing forecasts valid at 0000 UTC 30 October 2012 from EC forecasts initialized at a-d) 1200 UTC 21 October, b-e) 0000 UTC 22 October, and c-f) 1200 UTC 23 October 2012. Upper panels show the ensemble mean field and the standardized anomalies. Lower panels show each member 976, 992, 1008, and 1020 contours and the spread about the mean. Return to text.
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Figure 17. As in Figure 16 except for European Center (EC) ensemble forecast system showing forecasts valid at 0000 UTC 30 October 2012 from EC forecasts initialized at a-d) 0000 UTC 23 October, b-e) 1200 UTC 23 October, and c-f) 0000 UTC 24 October 2012. Return to text.
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Figure 18. As in Figure 16 except for NCEP GEFS initialized at a-d) 1200 UTC 21 October, b-e) 0000 UTC 22 October 2012, and c-f) 0000 UTC 23 October 2012. Return to text.
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Figure 19. As in Figure 18 except for NCEP GEFS initialized at a-d) 0000 UTC 24 October, b-e) 0000 UTC 25 October 2012, and c-f) 0000 UTC 26 October 2012. Return to text.
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Figure 20. As in Figure 18 except for the NCEP GEFS initialized at a-d) 1200 UTC 26 October, b-e) 0000 UTC 27 October 2012, and c-f) 1200 UTC 28 October 2012. Return to text.
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Figure 21. NCEP GEFS forecasts of QPF showing the probability of 100 mm or more QPF (upper panels) and the ensemble mean QPF (shaded) and each member’s 100 mm contour valid from 1200 UTC 29-31 October 2012 from NCEP GEFS initialized at a-d) 0000 UTC 24 October, b-e) 0000 UTC 25 October 2012, and c-f) 0000 UTC 26 October 2012. Return to text.
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Figure 22. As in Figure 21 except for GEFS initialized at a-d) 1200 UTC 26 October, b-e) 0000 UTC 27 October 2012, and c-f) 1200 UTC 27 October 2012. Return to text.
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Stations reporting wind gusts 50-59kt as of 1751 UTC (coolwx.com
FDBB: UNKNOWN, [53kt, 27m/s]
KFMH: Otis Air National Guard Base, MA, United States [50kt, 25m/s]
KFOK: Westhampton Beach, The Gabreski Airport, NY, United States [51kt, 26m/s]
KFRG: Farmingdale, Republic Airport, NY, United States [50kt, 25m/s]
KJFK: New York, Kennedy Intl Arpt, NY, United States [57kt, 29m/s]
KMVY: Vineyard Haven, Marthas Vineyard Airport, MA, United States [51kt, 26m/s]
KUUU: Newport, Newport State Airport, RI, United States [51kt, 26m/s]
SCCI: Punta Arenas, Chile [51kt, 26m/s]
CWEF: Saint Paul Island Meteorological Aeronautical Presentation System, Canada [57kt, 29m/s]
KFOK: Westhampton Beach, The Gabreski Airport, NY, United States [51kt, 26m/s]
KFRG: Farmingdale, Republic Airport, NY, United States [50kt, 26m/s]
KHYA: Hyannis, MA, United States [50kt, 26m/s]
KISP: Islip, Long Island Mac Arthur Airport, NY, United States [52kt, 27m/s]
KJFK: New York, Kennedy Intl Arpt, NY, United States [57kt, 29m/s]
KMQE: East Milton, MA, United States [51kt, 26m/s]
KMVY: Vineyard Haven, Marthas Vineyard Airport, MA, United States [51kt, 26m/s]
KUUU: Newport, Newport State Airport, RI, United States [51kt, 26m/s]
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Appendix Figure showing too far east tracks in 1200 UTC 23 and 24 October GFS.
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