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The Squall Line and Massachusetts Tornadoes of June 9, 1953

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The Squall Line and Massachusetts Tornadoes of June 9, 1953 VOL. 36, No. 3, MARCH, 1955 109 The Squall Line and Massachusetts Tornadoes of June 9, 1953 SAMUEL PENN, CHARLES PIERCE AND JAMES K. MCGUIRE U. S. Weather Bureau, Boston, Mass. (Manuscript received April 25, 1954) ABSTRACT Some features of the squall line situation of June 9, 1953 and accompanying tornadoes in central and eastern Massachusetts are discussed. From radarscope photographs, it is pointed out (1) that the Worcester tornado and the Franklin-Wrentham tornado each occurred in the right-rear quadrant of a squall-line thunderstorm cell, and (2) that this relative position, with an associated tail or hook in the radar echo, is similar to that of the Illinois tornado of April 9, 1953. A tentative explanation is suggested for tornado formation in this position. INTRODUCTION storms, violent in spots, were general over New ON the afternoon of June 9, 1953, two se- England. These disturbances accompanied the vere tornadoes roared through central and passage of a prefrontal squall line which developed eastern Massachusetts, while a third struck early that afternoon as a low pressure system Exeter, N. H. In addition, a "baby twister" was moved into the New England area. On the two reported from Rollinsford, N. H., and thunder- preceding days, squall line developments in the FIG. 1. Paths of the two Massachusetts tornadoes of June 9, 1953. Path widths exaggerated to show regions of maximum intensity. Dashed tracks indicate "skipping." Unauthenticated | Downloaded 10/08/21 09:01 PM UTC 110 BULLETIN AMERICAN METEOROLOGICAL SOCIETY FIG. 2. Photograph of tornado taken about 1625E 6 miles east of Worcester by Robert P. Resch, 2nd, of Westboro, Mass. Funnel estimated % mile away. FIG. 3. Surface chart for 1330E June 7, 1953. Unauthenticated | Downloaded 10/08/21 09:01 PM UTC VOL. 36, No. 3, MARCH, 1955 111 FIG. 4. Surface chart for 1930E June 8, 1953. same region of the Low generated tornadic ac- the fact that echoes from the thunderstorms as- tivity in the Great Plains, Mid-West and Great sociated with the Massachusetts tornadoes were Lakes regions. observed on radar sets operated by the Depart- In this paper, attention will be concentrated on ment of Meteorology of the Massachusetts In- the two Massachusets tornadoes whose paths are stitute of Technology, at Cambridge, Mass., un- given in FIGURE 1, and primarily on the first and der contract with the U. S. Army Signal Corps more devastating of these, the "Worcester tor- Engineering Laboratories, and by Project Lincoln nado". This storm, a photograph of which is of M.I.T. at Lexington, Mass. Through the shown in FIGURE 2, ranks among the most de- courtesy of these organizations, photographs of structive storms of its type on record for the radar echoes obtained on the afternoon of June 9 United States. The other Massachusetts tornado, were made available. It is proposed, then, to the so-called Franklin-Wrentham storm, was some- point out some of the features of the tornado situa- what less intense but still of major magnitude. tion on that date as revealed by a study of the Considerable information on both of these was synoptic background, the squall-line activity, and collected at the New England Climatological Sec- the radar scope photographs. tion Center of the U. S. Weather Bureau. In par- ticular, it was possible to construct detailed maps SYNOPTIC BACKGROUND of the paths of the tornadoes and to obtain a num- As is often the case, large-scale surface analysis ber of reliable time-checks on their movement. yielded few clues as to the mechanism of either the The value of such information is enhanced by squall line or the associated tornadoes. The fol- Unauthenticated | Downloaded 10/08/21 09:01 PM UTC 112 BULLETIN AMERICAN METEOROLOGICAL SOCIETY FIG. 5. Surface chart for 1330E June 9, 1953. lowing brief description gives the main sequence the first of the day's tornadoes occurred only five of events leading up to the disastrous Massachu- hours afterwards, and a squall line associated setts storms. with tornado activity is a feature of the 1930E The 1930E map of June 6 showed a Pacific map (FIG. 4). The widespread nature of this ac- front moving into the Rockies, whose northern tivity, however, suggests that more than one portion was occupied by a broad area of low squall line was involved, a conclusion which may pressure. On the morning of June 7, as the Pa- also be drawn from a synoptic study of the situa- cific front crossed over to the eastern side of the tion earlier on June 8. range, a well-defined Low formed in Eastern This same feature—violent activity following Colorado. That afternoon, tornadoes broke out quickly from a relatively quiescent situation—was in northeastern Colorado, western Nebraska and repeated on June 9. The night of the 8-9th and Iowa, some of these occurring in the vicinity of the morning of the 9th showed little or nothing in the pre-cold-frontal squall line which appears on the way of squall line weather as the system passed the 1330E map (FIG. 3) of June 7. During the over Pennsylvania and New York. On the early late afternoon and evening of the following day, afternoon of the 9th, however, squall line activity with the regeneration of squall line activity, south- developed afresh in west-central New England. eastern Michigan and northwestern Ohio experi- Violent hailstorms broke out in the northwestern enced widespread tornadic activity. The 1330E Massachusetts-southeastern Vermont-southwestern map of June 8 showed practically no showers or New Hampshire border region. Fanning out from thunderstorms in advance of the cold front, though this center, hailstorms developed during the course Unauthenticated | Downloaded 10/08/21 09:01 PM UTC VOL. 36, No. 3, MARCH, 1955 113 of the afternoon in two bands along the squall line. the property losses were caused by the first tor- One hail track extended eastward to the New nado, mainly in and around Worcester. Here the Hampshire coast, while the other led southeast- twister attained its greatest intensity and its maxi- ward across Massachusetts to Cape Cod. It is mum width, almost one mile. worth noting that the tornadoes occurred on the The 1330E, 1630E and 1930E sectional surface same segments of the squall line that produced maps of the 9th, given in FIGURES 5-7, delineate these hailstorms. the progress of the squall line across New Eng- The first tornado struck in Petersham, Mass., land. The first of these charts coincides closely shortly before 1525E and moved forty-six miles, with the outbreak of the hailstorms. The second as shown in FIGURE 1, to its point of dissolution map is near the time of the ending of the Wor- in Southborough about 1645E. The second cester tornado, the occurrence of the Exeter struck Exeter, N. H., around 1620E, while the twister, and the beginning of the second Massa- third (see FIG. 1) travelled a twenty-nine-mile chusetts tornado. The 1930E chart represents path, starting in Sutton, Mass., about 1630E and conditions after the tornadic activity had ended ending in Mansfield at 1737E. These three and the squall line, in other respects still vigorous, storms combined to take ninety lives, inflict over had swept east of New England except for Cape 400 major and close to 900 minor injuries, and Cod and northeastern Maine. Over Cape Cod destroy an estimated $60,000,000 in property. All that evening there was a magnificent display of the fatalities, most of the injuries, and the bulk of vivid, continuous lightning for nearly three hours. FIG. 6. Surface chart for 1630E June 9, 1953. Unauthenticated | Downloaded 10/08/21 09:01 PM UTC 114 BULLETIN AMERICAN METEOROLOGICAL SOCIETY FIG. 7. Surface chart for 1930E June 9, 1953. FIG. 8. 850-mb chart for 1030E June 7, 1953. FIG. 9. 850-mb chart for 1030E June 8, 1953. Unauthenticated | Downloaded 10/08/21 09:01 PM UTC VOL. 36, No. 3, MARCH, 1955 115 FIG. 10. 850-mb chart for 1030E June 9, 1953. THE SQUALL LINE The synoptic parameter most closely associated FIG. 11. Plotted raob sounding for Mt. Clemens, Mich., with the squall line in this case was warm-air 1030E June 7 and 8, 1953. advection in the lowest layers of the atmosphere. This statement is not meant to offer the advec- tion as a mechanism for the squall line, but to point out its importance as a means of affecting the thermal stratification of the air in advance of the cold front. Several investigators have called attention to relationships between squall lines and various types of advection. Newton [1] mentions that a warm tongue at 850 mb is very often found in advance of a pre-colcl-frontal squall line, and states that the squall line will dissipate upon reach- ing the axis of the warm tongue. According to Crawford [2] and MacDonald [3], a squall line develops along the axis of an 850-mb warm tongue, in conjunction with certain features of 700-mb cold-air advection. In the case under examination, the squall line on June 7th lay immediately to the west of the 850-mb warm tongue. The squall lines that de- veloped on the next two days appeared in the same relative position. FIGURES 8-10 give the 850-mb charts for June 7, 8 and 9; FIGURE 11 contains the Mount Clemens, Mich., raobs for the 7th and 8th; FIGURE 12 shows the Portland, Me., and FIGURE 13 the Hempstead, N. Y., raobs for the 8th and 9th. These clearly indicate the effect FIG. 12.
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