Severe Thunderstorm and Tornado Outbreak, Sunday May 31, 1998
(Mechanicville-Stillwater Tornado)

Coming only one day after widespread severe thunderstorms produced damaging wind throughout eastern New York and western New England, a severe thunderstorm and tornado outbreak of almost unprecedented magnitude and duration struck the Northeast during the afternoon and early night time hours of Sunday, May 31. An estimated thirty tornadoes touched down across New York state alone in the outbreak, with a particularly damaging tornado plowing through the Mechanicville/Stillwater areas of Saratoga county, NY and Schaghticoke in Rensselaer county. An average year will only produce between 15 and 20 tornadoes state wide in New York. The severe weather continued east into New England with reports of fatalities in central Massachusetts due to a fallen tree on a vehicle. 60,000 customers were left without electricity after the storms in the Capital District alone, with up to 150,000 without electricity regionally. Many areas remained in the dark for up to four days after the outbreak. Damage estimates exceeded one hundred million dollars in the Capital District, most from the Mechanicville tornado. Fortunately, and perhaps as a by product of superior warnings by the Albany National Weather Service and Capital District media outlets, no fatalities occurred in eastern New York or western New England as a direct result of the storms.

Storm Setup & Timeline:
The cold front responsible for a widespread severe weather producing squall line on Friday, May 29, pushed south of the region and stalled over southern Pennsylvania on Saturday, May 30. A weak bubble of Canadian high pressure, associated with very dry air, moved over New York and New England producing a beautiful Saturday weatherwise. Dewpoint temperatures dropped from the muggy 60's on Friday into the upper 30's on Saturday with mostly clear skies.

The jet stream flow across the northern U.S., however was quite strong, blowing up to 150 mph from west to east. The jet on Saturday, May 30 was supporting a storm system which produced a tornado that leveled the entire town of Spencer, South Dakota. The low pressure system responsible for the Spencer tornado had intensified and raced east to northern Michigan by 8:00 am Sunday morning, May 31. The counterclockwise flow around the cyclone pushed the stalled front, previously over southern Pennsylvania north into the Berkshires by 8:00am. Very warm, humid air was now clashing with the cooler, dry air over the Berkshires, resulting in several large, locally damaging thunderstorms which produced heavy rain, frequent lightning, and isolated damaging downburst winds. Simultaneously, in the low pressure system's warm sector, a derecho (a highly organized complex of severe thunderstorms which produce widespread wind damage) was moving across eastern Michigan.   The derecho produced convective wind gusts up to 100 mph across Michigan as well as isolated tornadoes. The first of what would be several tornado watch areas was issued early in the morning for much of western and northern New York to cover the severe weather threat with this derecho as it raced through Canada and moved into New York.

With western and northern New York under an early morning gun, sunshine was breaking out in eastern New York and western New England and dewpoint temperatures began rising quickly as the warm front passed. By early Sunday afternoon the dewpoint temperatures had reached sultry readings in the upper 60's and air temperatures had climbed into the 70's and low 80's. Surface winds began blowing up to 30 mph out of the southeast. Upper air winds, however, were blowing between 40 and 80 mph out of the west. The dramatic change in wind direction and speed with height created a highly wind sheered environment which is favorable for developing thunderstorms with rotating updrafts, called supercell thunderstorms.  Most supercell thunderstorms produce some type of severe weather in the form of damaging wind or very large hail.  About sixty percent of all supercells go on to produce tornadoes. It's fairly rare in the Northeast to develop such a highly wind sheered environment in the atmosphere, but the combination of the deepening surface low tracking over southeast Canada and the strong upper level jet, supported the sheer, which ultimately supported a widespread outbreak of tornadic thunderstorms.

By 1pm the initial line of severe thunderstorms (the Michigan derecho) was weakening and moving into the Adirondacks, still producing damaging wind. The main tornado event developed along the outflow boundary (a zone of rain cooled air, almost a mini cold front) of the derecho which sagged south into the Mohawk valley and Capital District.  The outflow boundary acted as a lifting mechanism in the atmosphere.  As the rain cooled air moved south, it interacted with the strong southeast surface winds that were pumping the very warm and very humid air into the boundary.  The interaction of air at the boundary caused powerful updrafts to form which turned into rotating thunderstorms.    A tornado watch was issued by 2:30pm for all of eastern New York and western New England. The first tornadic supercell then formed on the outflow boundary in Montgomery county around 3:30pm. This storm rapidly intensified and moved east at 50mph into Saratoga county. This first supercell of the outbreak locally, produced the devastating F-3 (165 mph) tornado which moved through Mechanicville and Stillwater, NY at 4:20 pm, finally dissipating over Shaftsbury, Vermont later in the afternoon. By 4:30pm, severe thunderstorms had developed throughout the region with many areas being effected by frequent lightning, high wind, hail, and torrential rain.  Most of these thunderstorms had rotating updrafts.  At 4:40 pm a second tornado developed from a supercell at the Albany International Airport. A peak wind gust of 82 mph was recorded with the passage of that storm. From 3:30 pm to 7:00 pm almost every county in the Channel 6 viewing area in New York and New England experienced severe weather in the form of large hail, damaging straight line winds or tornadoes.

A short break from the weather developed in the Capital District during the late afternoon and evening before a second round of severe thunderstorms and tornadoes moved into the region from the west. The second round of storms produced more violent lightning, damaging straight line winds and tornadoes through the region.   The entire event finally ended by 10:30 pm with the passage of the cold front.

The Albany National Weather Service issued approximately forty six severe weather warnings for eastern New York and western New England, most of them tornado warnings, the most tornado warnings the Albany National Weather Service forecast office had every issued for a single event. Doppler radar indicated rotation in most of the storms which formed and moved across our area, certainly a very rare type of severe weather outbreak for this part of the country. This event is a classic example that widespread outbreaks of severe weather more typical of the central Plains states can happen in the Northeast and that we need to be prepared.

Mechanicville Tornado Aftermath Photographs (Photographs by Steve LaPointe)

Tornado winds of up to 200 mph produced extensive damage to the Viall Hill section of Mechanicville and Stillwater on May 31, 1998.  The photographs show the damage in the Viall Hill area as well as the Route 4/32 area.

Photograph #1 of 9

The roof and many interior walls blown out of this home with the front lawn littered with debris from other homes

Photograph #2 of 9

This structure was declared a complete loss with the roof and much of the second floor missing.

Photograph #3 of 9

This home was in the direct path of the tornado and was completely destroyed.   Meteorologist survey tornado damage to rank the intensity of the storm.   Damage of the magnitude shown in this photograph indicates and F-3 borderline F-4 tornado on the Fujita tornado intensity scale.

Photograph #4 of 9

Trees adjacent to this home were twisted apart and stripped of their foliage. An automobile was thrown through the air landing at the base of the trees in a pile of debris.

Photograph #5 of 9

Only a shell remained of this structure with the roof gone and windows and walls blown out.

Photograph #6 of 9

Winds of 165 mph stripped this home completely from its foundation reducing it and it's contents to debris.

Photograph #7 of 9

Considerable damage occurred to these buildings facing the Hudson river as the tornado moved towards Rensselaer county.

Photograph #8 of 9

This Ford Taurus was lifted and thrown several hundred yards landing in this yard.

Photograph #9 of 9

This small section of the Viall Hill neighborhood was ground zero with the complete destruction of trees and several homes.

 

The table lists the tornado and damage reports, collected by channel 6 and the National Weather Service, for the counties in the Channel 6 coverage area for this outbreak.

Town

County

State

Storm Report

Estimated Time

Fonda Montgomery NY Wind damage, Trees down 3:42 pm
Mohawk Herkimer NY Tornado on Showmaker Hill Road 3:45 pm
Milton Center Saratoga NY One inch diameter hail 4:15 pm
Stillwater Saratoga NY Major Tornado, massive destruction 4:20 pm
Mechanicville Saratoga NY Major Tornado 4:20 pm
Saratoga Springs Saratoga NY 1.75" diameter hail 4:20 pm
Cooperstown Otsego NY Wind damage 4:20 pm
Laurens Otsego NY Wind damage 4:20 pm
S. Washington County Washington NY Tornado 4:28 pm
N. Adams Berkshire MA Wind damage, 55 mph winds at airport 4:28 pm
Midleburg Schoharie NY Wind damage, 60 mph wind gust 4:32 pm
Bethlehem Center Albany NY Wind damage 4:38 pm
Albany Airport Albany NY 82 mph wind gust and an F-1 Tornado 4:40 pm
Bennington Bennington VT Wind damage, Trees and wires down 4:45 pm
Colonie Albany NY Wind damage, Trees and wires down 4:50 pm
Schaghticoke Rensselaer NY Tornado 4:50 pm
Stuyvesant Columbia NY Wind damage, trees down 5:10 pm
Chatham Columbia NY .75" diameter hail 5:10 pm
Kinderhook Columbia NY Wind damage, trees down 5:10 pm
Pittsfield Berkshire MA Wall cloud and tornado over airport 5:27 pm
Stuyvesant Columbia NY Once inch diameter hail 5:31 pm
Nassau Rensselaer NY Wind damage 5:35 pm
Pittsfield Berkshire MA One inch diameter hail 5:45 pm
Unadilla Otsego NY Tornado 5:52 pm
Hartwick Otsego NY Wind damage, numerous trees down 6:22 pm
Milford Otsego NY F-2 Tornado, roofs blown off homes 6:22 pm
Mohawk Herkimer NY Wind damage, trees and power lines down 6:25 pm
Clarksville Albany NY Wind damage 6:30 pm
New Scotland Albany NY Wind damage 6:40 pm
Little Falls Herkimer NY Tornado 6:41 pm
Breakabeen Schoharie NY Wind damage, trees down 6:47 pm
Mechanicville Saratoga NY Wind damage 7:08 pm
Duanesburg Schenectady NY Wind damage, trees down 7:15 pm
East Schodack to Nassau Columbia NY Tornado 7:15 pm
Guilderland Center Albany NY Tornado 7:16 pm
Selkirk Albany NY Tornado, damage to industrial buildings 7:35 pm
Schoharie County Schoharie NY Wind damage county wide 7:35 pm
Greenwich Washington NY Wind damage 7:35 pm
Stephentown Rensselaer NY .75" diameter hail (Dime size) 7:42 pm
North Adams Berkshire MA 70 mph wind gust observed 7:55 pm
Great Barrington Berkshire MA .75" inch diameter hail 8:00 pm
Saugerties Ulster NY Wind damage 8:00 pm
Pittsfield Berkshire MA Tornado near Franklin Street 8:03 pm
Cairo Greene NY Tornado 8:15 pm
Catskill Greene NY .75" inch diameter hail 8:23 pm
Catskill Greene NY Tornado 8:24 pm
Pownal Bennington VT Wind damage 8:40 pm
Medusa Albany NY Wind damage 9:15 pm
Rhinebeck Dutchess NY Widespread wind damage 9:30 pm
New Milford Litchfield CT Wind damage, trees down 9:50 pm