The Historical 11-12 December 2008 Ice Storm

(Click on thumbnails for larger images)

 

A cold front moved across the region Wednesday, December 10th ushering in a cold airmass back into the region. A low pressure system developed over the southeastern states Wednesday and Wednesday night. This storm then headed northeast Thursday and Thursday night with precipitation spreading northward well in advance of the low. The low continued to track northeast passing over the mid Atlantic region late Thursday night and over the New York Metropolitan area and southern New England Friday morning. The low moved to the Canadian Maritimes Friday night.

As the storm approached warmer air moved in aloft and with a cold airmass in place at the surface, this set the stage for a mixed precipitation event. The precipitation came down heavy at times, especially Thursday night. Hourly precipitation rates of quarter to a third of an inch were reported for several hours in the form freezing rain across much of the forecast area. Thunder was even reported in Glens Falls. By the time the precipitation tapered off Friday morning ice accumulations ranged from around half of an inch up to an inch across portions of the Capital District and the Berkshires. North and west of the Capital District temperatures were colder and frozen precipitation fell. Snowfall reports ranged from 2 to 4 inches just north and west of the Capital District, where sleet mixed in along with lesser ice accumulations, up to 8 to 12 inches across portions of the southern Adirondacks.

Across the central and southeastern Catskills, mid Hudson Valley into the Berkshires and Litchfield County heavy rainfall, 2 to 4 inches, lead to widespread urban and small stream flooding with some river flooding. River flooding was observed on the Hoosic River, Esopus Creek, Housatonic River, Batten Kill, Still River and Wappingers Creek. The Housatonic River reached moderate flooding levels at Falls Village, Gaylordsville and at Stevenson Dam.

In the wake of the storm, temperatures tumbling Friday night with teens across much of the local area, single digits across the higher terrain and even below zero temperatures across portions of the Adirondacks. There was little recovery on Saturday as arctic high pressure crested over the region. Temperatures began to moderate Sunday as the high shifted offshore and winds become southerly.

There was widespread tree and power line damage across the local area. An estimated 350,000 utility customers lost power across East Central New York and adjacent western New England. Over 60,000 customers were still out of power Monday morning, December 15th and over 10,000 customers were still out of power Wednesday morning, December 17th.

9 December 2008 Forecast Data

a) b) c) d) e)

Figure 1. Forecasts of 500 hPa height and absolute vorticity from 12Z 9 December from a) GFS40, b) NAM80, c) ECMWF, d) GFSEnsemble, e) SREF.

a) b) c) d) e)

Figure 2. Forecasts of MSLP from 12Z 9 December from a) GFS40, b) NAM80, c) ECMWF, d) GFSEnsemble, e) SREF.

a) b) c) d) e)

Figure 3. Forecasts of 850 hPa and 925 hPa temperatures from 12Z 9 December from a) GFS40, b) NAM80, c) ECMWF, d) GFSEnsemble, e) SREF.

a) b) c)

Figure 4. Forecasts of 24 hour liquid equivalent precipitation from 12Z 9 December from a) GFS40, b) NAM80, c) ECMWF.

a) b)

Figure 5. Forecast probabilities of 24 hour 1 liquid equivalent precipitation valid 12Z 11 December to 12Z 12 December from a) 12Z 9 December GEFS, b) 15Z 9 December SREF.

a) b)

Figure 6. Plume diagrams from the 12Z 9 December GEFS for a) Albany, NY, and b) Bradley, CT.

a) b) c)

Figure 7. Plume diagrams from the 15Z 09 December SREF for a) Albany, NY, b) Bradley, CT and c) Saranac Lake, NY.

Figure 8. HPC WWE 3-day forecast of snow and ice from 18Z 9 December with snow amounts color shaded and ice amounts as brown contours.

Figure 9. Precipitation type forecast from 15Z SREF 9 December valid 00Z 12 December.

Figure 10. Forecast 850 hPa U and V winds from the 12Z 9 December GEFS.

10 December 2008 Forecast Data

a) b) c)

Figure 11. Forecasts of 500 hPa height and absolute vorticity from 12Z 10 December from a) GFS40, b) NAM80, and c) ECMWF.

a) b) c)

Figure 12. Forecasts of MSLP from 12Z 9 December from a) GFS40 and NAM80 overlayed, b) GFSEnsemble, and c) 15Z 10 December SREF mean.

a) b) c) d)

Figure 13. Forecasts of 850 hPa and 925 hPa temperatures from 12Z 10 December from a) GFS40, b) NAM80, c) ECMWF, and d) GFSEnsemble.

a) b)

Figure 14. Forecasts of 24 hour liquid equivalent precipitation from 12Z 10 December from a) GFS40, and b) NAM80.

a) b)

Figure 15. Forecast probabilities of 24 hour 1 liquid equivalent precipitation valid 18Z 11 December to 18Z 12 December from a) 12Z 10 December GEFS, b) 15Z 10 December SREF.

a) b)

Figure 16. Forecast probabilities of 36 hour 2 liquid equivalent precipitation valid 06Z 11 December to 18Z 12 December from a) 12Z 10 December GEFS, b) 15Z 10 December SREF.

a) b)

Figure 17. Precipitable Water valid 06Z 12 December from the a) 12Z 10 December GEFS and b) 15Z 10 December SREF.

a) b)

Figure 18. Forecast 850 hPa U and V winds from a) the 12Z 10 December GEFS valid 06Z 12 December and b) 15Z SREF valid 12Z 12 December.

a) b)

Figure 19. Forecast 925 hPa U and V winds from a) the 12Z 10 December GEFS valid 06Z 12 December and b) 15Z SREF valid 12Z 12 December.

a) b)

Figure 20. Precipitation type forecast from 15Z SREF 10 December valid a) 00Z 12 December and b) 06Z 12 December.

a) b)

Figure 21. Plume diagrams from the 12Z 10 December GEFS for a) Albany, NY, and b) Bradley, CT.

a) b) c) d)

Figure 22. Plume diagrams from the 15Z 10 December SREF for a) Albany, NY, b) Bradley, CT c) Monticello, NY and d) Saranac Lake, NY.

12 December 2008 Observational Data

a) b)

c) d)

Figure 23. Upper plots from 12Z 12 December for a) 925 hPa, b) 850 hPa, c) 500 hPa and d) 300 hPa.

Figure 24. Loop of surface maps from HPC from 21Z 11 December through 12Z 13 December. Click on map for java loop.

a) b)

c) d)

Figure 25. Upper air soundings from Albany, NY (KALB) from a) 12Z 11 December, b) 18Z 11 December, c) 00Z 12 December and d) 12Z 12 December.

a) b)

Figure 26. Radar reflectivity from a) 18Z 11 December, and b) 00Z 12 December (courtesy rap.ucar.edu).

a) b)

c) d)

Figure 27. Radar reflectivity from a) 06Z 11 December, b) 09Z 12 December, c) 12Z 12 December and d) 15Z 12 December (courtesy rap.ucar.edu).

a) b)

c) d)

Figure 28. Water vapor satellite imagery with lightning overlay from a) 1945Z 09 December, b) 2131Z 10 December, c) 2315Z 11 December and d) 1245Z 12 December.

a) b)

Figure 29. Visible satellite imagery with lightning overlay from a) 2030Z 11 December and b) 1345Z 12 December.

a) b)

Figure 30. List of surface observations from 12 December from a) Albany, NY and b) Glens Falls, NY.

a) b)

Figure 31. Observed liquid equivalent precipitation from a) 11 December and b) 12 December.

a) b) c)

Figure 32. Power outages for a) Connecticut, b) Vermont and c) western Massachusetts. (Courtesy Green Mountain Power Company, National Grid and Northeast Utilities.

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Pictures

Above pictures by Neil A. Stuart. The first 8 pictures are in North Colonie on 12-13 December and the bottom 3 are on I-90 between Rensselaer County and Pittsfield, MA on 14 December.

Photo by: Judy HagemannPhoto by: Judy Hagemann

Above 4 pictures by Judy Hageman in Brunswick, NY.

Photo by: Ingrid AmbergerPhoto by: Eric AmbergerPhoto by: Eric Amberger

Photo by: Ingrid AmbergerPhoto by: Ingrid AmbergerPhoto by: Ingrid AmbergerPhoto by: Ingrid Amberger

Above 8 pictures by Ingrid and Eric Amberger, taken in Niskayuna, NY and Colonie, NY.

Top 2 pictures are Beaver Ridge in Schoharie County, NY and Round Top Mountain in Green County, NY. Bottom 2 pictures are from Chatham, NY and the Mohawk River near Cohoes, NY.