1JULY 2002 SCHWARTZ AND SCHMIDLIN 1765

Climatology of in the Conterminous United States, 1959±2000

ROBERT M. SCHWARTZ Department of Geography, Ball State University, Muncie, Indiana

THOMAS W. S CHMIDLIN Department of Geography, Kent State University, Kent, Ohio

(Manuscript received 24 August 2001, in ®nal form 27 December 2001)

ABSTRACT

A is de®ned by the U.S. National Weather Service as winds over 16 m s Ϫ1 and falling or blowing causing visibility less than 400 m lasting for at least 3 h. Blizzard occurrence by county was tallied from Storm Data for the 41 winters from 1959/60 to 1999/2000. This revealed 438 blizzards for an annual average of 10.7, ranging from 1 blizzard in 1980/81 to 27 blizzards in 1996/97. The average area affected per blizzard was 150 492 km2 and the average number of people in affected counties was 2 462 949 per blizzard. There was a signi®cant linear increase in the number of blizzards but no linear trend in the total area affected by blizzards or the population in affected counties during the period. Blizzards were most common in a ``blizzard zone'' of North Dakota, South Dakota, and western Minnesota where each county had 41 or more blizzards in these 41 winters and the annual probability of a blizzard in each county exceeded 50%. Monthly occurrence of blizzards peaked during January in most areas, but during December in the Sierra Nevada, during March in the central , and during April in Montana. There was weak correlation between the ENSO phase and the number of blizzards, with a tendency for more blizzards during La NinÄa and fewer during El NinÄo.

1. Introduction sands of travelers. This is a hazard to human health and may cause death due to exposure, asphyxiation, or suf- Severe winter storms are signi®cant natural hazards. focation to those trapped in cars, or lead to death in- They cause disruptions to transportation, wind damage directly through heart attacks as people overexert while to buildings, loss of retail sales, closure of schools and walking in the blizzard or attempting to clear deep snow- businesses, loss of electricity, and hazards to human drifts (Changnon and Changnon 1978; Rooney 1967). health causing morbidity and mortality (e.g., Rooney 1967; Babin 1975; Changnon and Changnon 1978; The northeastern United States blizzard of January 1996 Graff and Strub 1975; Helburn 1982; McKay 1981). killed 154 in 17 states (Lott et al. 1996); the northern Signi®cant impacts from severe winter weather in North Great Plains blizzard of January 1975 caused 80 deaths America can occur in northern latitudes where snow and (Graff and Strub 1975); the Midwest blizzard of January subfreezing weather occur for several months each win- 1978 killed 73 (Schwartz 2001); 29 died in the Buffalo ter (Stommel 1966; Babin 1975; Graff and Strub 1975) blizzard of January 1977 (Dewey 1977); and 27 people, and in southern latitudes where snow and extreme cold mostly stranded motorists, died in the Midwest blizzard are rare events (Conner et al. 1973). of March 1966 (Haines 1966). Strong winds of a severe The most extreme form of is the bliz- blizzard may cause damage to buildings, signs, and oth- zard, combining strong winds and falling or blowing er structures. Extensive drifting snow on roofs of build- snow to cause low visibility, deep snowdrifts, and ex- ings can lead to collapse of structures due to extreme treme wind chill. This combination of strong winds and snow loads, as occurred in the northeastern United blowing snow causes a general cessation of routine so- States following the 6±8 January 1996 blizzard (De- cietal activities making the blizzard the most dangerous Gaetano et al. 1997). Utility lines may be blown down of winter storms. Blizzards can cause closures of high- in a blizzard resulting in loss of electric, telephone, and ways, railroads, and airports, potentially stranding thou- cable television service. Reduction in retail sales and absenteeism cause ®nancial losses to business and in- dustry (Burrows et al. 1979). A 5-day blizzard in Buf- Corresponding author address: Dr. Thomas W. Schmidlin, De- falo, NY, in January 1977 caused losses of $250 million partment of Geography, Kent State University, P.O. Box 5190, Kent, OH 44242-0001. in storm damage, snow removal costs, lost wages, and E-mail: [email protected] lost production (Dewey 1977). Schools and government

᭧ 2002 American Meteorological Society

Unauthenticated | Downloaded 10/06/21 02:58 PM UTC 1766 JOURNAL OF CLIMATE VOLUME 15 of®ces are forced to close due to dif®culties and dangers States include Black's (1971) synoptic climatology of of travel and, in some cases, due to loss of electricity blizzards in the northern Great Plains during 1957±67, and heat. Isolation of families and communities occurs and Branick's (1997) study of signi®cant winter weather when highway travel and electric and telephone service events during the period 1982±94. Other studies have are curtailed by a blizzard. Those with acute health prob- focused on the meteorology of blizzards (Fox 1952; lems must be transported to a hospital through extraor- Salmon and Smith 1980) and other winter storms (e.g., dinary means, such as snowmobile or helicopter, or risk Kocin and Uccellini 1990) or impacts of individual win- loss of life. Livestock deaths during a blizzard may total ter storms, as cited above. There has been no modern in the tens of thousands (Stommel 1966; Changnon and climatology of blizzards for the conterminous United Changnon 1978; Graff and Strub 1975; Steppuhn 1981) States. The purpose of this research was to determine and wildlife may be killed through cold or starvation the occurrence and location of blizzards in the conter- (Graff and Strub 1975). Strong winds and blowing snow minous United States over recent decades, summarize during blizzards in mountainous terrain can cause rapid the data into a modern climatology of blizzards, and loading of snow on slopes and increase the risk of av- analyze the data for time trends, spatial patterns, and alanches (Barry 1992, p. 357; Fredston and Fesler 1994, relationships with the El NinÄo±Southern Oscillation p. 71). (ENSO) teleconnection. The area and population of The term ``blizzard'' was ®rst used by Henry Ellis counties affected by blizzards was also analyzed. The along Hudson Bay in 1746 (Black 1971) although Ellis's results may have utility in the study of climate change, meaning at the time was ambiguous (Wild 1997). Lud- impacts of natural hazards, emergency management and lum (1968) reported that the term was ®rst used in the preparedness, winter weather forecasting, insurance, United States to describe the winter storm of March transportation planning, and the study of concurrent or 1870 in Iowa, however Wild (1997) reported use in resultant hazards, such as severe thunderstorms or snow- South Dakota newspapers in 1867. The term was in melt ¯ooding. general use by the 1880s (Wild 1997). The current def- inition of a blizzard used by the National Weather Ser- 2. Methods vice (NWS) is winds over 16 m sϪ1 [35 miles per hour (mph)] and falling or blowing snow causing visibility A climatology of blizzards could be developed from of less than 400 m (0.25 miles) lasting for at least 3 h. a review of historical weather conditions at of®cial An additional criterion for temperatures below 20ЊF weather stations and noting the simultaneous occurrence (Ϫ7ЊC) was used for many years but was abandoned in of wind speed over 35 mph, visibility less than one- the 1970s (M. L. Branick, 2000, personal communi- quarter mile, and the presence of blowing snow. The cation). There remains some confusion about the de®- existence of these conditions for 3 or more hours would nition of a blizzard in the United States. The glossary constitute a blizzard and these occurrences could be sum- of the ``Encyclopedia of Weather and Climate'' (North marized and analyzed for a period of time over the United 1996, p. 855) gives the de®nition as used by the NWS: States. This approach was not taken here because the ``Falling snow over a sustained duration with speeds weather stations recording wind speed and visibility were greater than 15 meters per second (35 miles per hour) generally limited to ®rst-order NWS of®ces that, even and visibility less than 400 meters (0.25 miles) over an prior to NWS modernization and closure of many of®ces, extended period.'' However, in the same publication on were located 150±300 km apart. Thus, the spatial reso- p. 700, Cohen (1996) states: ``The blizzard is de®ned lution of blizzard conditions was poor. In addition, the by three criteria: signi®cant accumulationÐusually 25 ®nest time resolution was hourly and for a portion of the centimeters or moreÐor blowing of snow that reduces record the ®nest resolution was every 3 h. visibility to less then 400 meters (one-quarter mile); We chose instead to use the description of blizzards sustained winds of at least 56 kilometers (35 miles) per in the publication Storm Data. Storm Data is widely hour; and temperatures of Ϫ7ЊC (20ЊF) or less'' and used in the climatology of severe weather (Curran et al. states that ``this last criterion has recently been dropped 2000; Gaf®n and Hotz 2000; Lopez et al. 1995), in- in some locations.'' A recent textbook in physical ge- cluding severe winter weather (Branick 1997). The ography de®nes a blizzard as a ``heavy snowstorm'' with Warning Coordination Meteorologist (WCM) at each winds more than 16 m sϪ1 and visibility less than 150 NWS of®ce submits storm reports for publication in the m (Scott 1996, p. 194). A blizzard in Canada is de®ned monthly Storm Data, specifying the type of storm event, as wind speed over 40 km hϪ1 (11msϪ1), wind chill counties or regions of a state impacted by the event, greater than 1600 W mϪ2, visibility less than 1 km in date and times of impact, and estimates of damages, snow, with a duration of at least4h(6hprior to 1991; injuries, and deaths. Storm Data is available in paper Stewart et al. 1995). The Met Of®ce de®ned a blizzard copy since January 1959 and online with an event da- as wind speed over 56 km hϪ1 (15 m sϪ1) causing drift- tabase since 1993. The quality of data in Storm Data ing snow and reduction of visibility to 200 m (Wild may vary with the WCM preparing the report, the time 1997). available to spend investigating each event, and care Recent climatologies of winter storms in the United taken in the written summary. Although there may be

Unauthenticated | Downloaded 10/06/21 02:58 PM UTC 1JULY 2002 SCHWARTZ AND SCHMIDLIN 1767 some spatial and temporal variability in the quality of the reports in Storm Data (Branick 1997), the publi- cation is an of®cial archive of storm events in the United States. Monthly issues of Storm Data were scanned over the 41 winters from October 1959 to May 2000 for each storm report of a blizzard or ``blizzard conditions'' in the 48 conterminous states, as described in the ``char- acter of storm'' column or within the text of the storm description. We recorded the date of the storm, counties reported to have had blizzard conditions, the estimate of monetary damages, and number of injuries and deaths caused by the blizzard. Reports of ``near-blizzard con- ditions'' were not counted as blizzards. Some reports did not list counties affected, but just regions, such as ``northwest Iowa'' or ``western Nebraska.'' In those cas- FIG. 1. Number of blizzards identi®ed each winter. es, the map of forecast zones was used to assign counties when available, otherwise a consistent and logical meth- od was used to assign the counties affected in the regions (by winter) averaged 10.7 and ranged from 1 blizzard speci®ed. The task of the WCM to determine the borders in 1980/81 to 27 blizzards in 1996/97 (Fig. 1). A linear of the area that had a blizzard rather than a severe winter regression showed a positive trend in the number of storm that did not meet blizzard criteria is dif®cult and blizzards during 1959±2000 (slope ϭ 0.21 blizzards there may be differences among NWS of®ces in how yrϪ1, p ϭ 0.001). This yielded a modeled increase from precise or carefully these distinctions were made and 6.6 blizzards at the beginning of the study period to recorded in Storm Data. 15.2 at the end. The standard error of the estimate was For each blizzard identi®ed in Storm Data, each coun- 4.7. Whether the increase in the number of blizzards is ty affected was recorded and entered into a database. This allowed a tally of blizzards by date and county for a true climatological increase or is due to increased the United States and presentation of annual and month- reporting ef®ciency in Storm Data, or both, is not ly patterns of blizzards. The area (km2) affected by each known. blizzard was calculated with ArcView software and us- The frequency of blizzards by county over the period ing the ArcView Geographic Information System (GIS) 1959±2000 is shown in Fig. 2. Forty of 48 states re- database, as compiled from the U.S. Census Bureau. ported a blizzard during the period. Blizzards were most Annual probability of a blizzard was calculated empir- common in the northern Great Plains where 17 counties ically for each county by dividing the number of winters in North Dakota and 8 counties in South Dakota had with a blizzard by the number of years in the database more than 60 blizzards during 1959±2000. Traill Coun- (41). The annual number of blizzards, the annual area ty, North Dakota, had 74 blizzards in the 41-yr period, affected by blizzards, and total population in affected the most of any county in the conterminous United counties each winter were analyzed for time trends with States. A region that we are calling the U.S. ``blizzard linear regression in the statistical analysis software zone'' occupied all of North Dakota and South Dakota SPSS. The annual number of blizzards was checked for and 34 counties in western Minnesota. Each county in correlation with ENSO using the Climate Prediction the blizzard zone had 41 or more blizzards in the 41 Center database (CPC 1999). ENSO was characterized winters, for an average of one or more blizzards per for the October±December and January±March periods winter. each winter. The warm-phase El NinÄo events were coded Outside of the blizzard zone, there were 21±40 bliz- as strong, moderate, or weak (and assigned values of 3, zards per county during 1959±2000 in the rest of Min- 2, or 1, respectively). The cold-phase La NinÄa events nesota, northern and central Iowa, most of Nebraska, were coded as strong (Ϫ3), moderate (Ϫ2), or weak northwest Kansas, eastern Colorado, southeast Wyo- (Ϫ1). Neutral events were coded as zero. The population ming, and eastern Idaho. The blizzard frequency de- in counties affected by each blizzard was tallied from creased to 11±20 per county in the northern and central the U.S. Census Bureau Web site (2001), using 1960 Rockies, central Great Plains, and western Midwest. census data for the winters 1959/60 to 1968/69, 1970 Other areas with 11±20 blizzards during the period were census data for the winters 1969/70 to 1978/79, and so on. in Erie County (Buffalo), ; Garrett County, ; all of ; and portions of southeastern . Hancock and Washington counties, 3. Results Maine, each had 18 blizzards, the largest number in the a. Annual blizzard frequency . There were 4±10 blizzards per There were 438 blizzards identi®ed for the 41 winters county during 1959±2000 across the remainder of the 1959/60 to 1999/2000. The annual number of blizzards northeastern United States, the , the

Unauthenticated | Downloaded 10/06/21 02:58 PM UTC 1768 JOURNAL OF CLIMATE VOLUME 15

FIG. 2. Number of blizzards recorded by county during the 41 winters 1959/60 to 1999/2000.

High Plains of Texas and , and the Sierra by the blizzards ranged from 1482 km2 in the Cape Cod, Nevada Mountains. Massachusetts, blizzard of 26 January 1987 to 1 054 779 The depiction of blizzard occurrences in the moun- km2 in the 24±27 January 1978 Midwest storm that tainous western states is hampered by the large size of brought blizzard conditions to 9 states. Although the counties and the wide variety of topography and weather number of blizzards increased through the period, the within large western counties. For example, Los An- total area affected by blizzards each winter (Fig. 3) geles County, California, had a blizzard on 21±22 De- showed no linear trend through time (slope ϭ 10 105 cember 1996, but the effects were limited to a small km2 yrϪ1, p ϭ 0.45). If these data represent the true area in the less-populated elevations above 1830 m number and areas of blizzards, then the average size of (6000 ft) elevation. The entire county is depicted in our blizzards must be getting smaller. It may also be that county-level maps (Figs. 2, 4, and 5) and the entire the NWS is recording smaller, weaker blizzards in recent county was used for the calculation of affected popu- years that went unrecorded earlier in the period, as oc- lation, as described below. Therefore, the area and pop- curred also in the of®cial record of tornadoes in the ulation affected by blizzards may be overestimated in United States (Fujita 1987; Brooks and Doswell 2001). the western states. c. Annual probability of a blizzard by county b. Area affected by blizzards Annual probability of a blizzard (Fig. 4) exceeded The average area affected by the 438 blizzards was 50% through all counties of North Dakota and Min- 150 492 km2, about the size of Iowa. The area affected nesota, most of South Dakota, western Nebraska, north- west Iowa, and northeastern Colorado. The largest cities in this region are Minneapolis, St. Paul, St. Cloud, Du- luth, Sioux Falls, Rapid City, Fargo, Grand Forks, and Greeley. Annual probability of a blizzard was greatest, 63%±76%, across all of North Dakota and adjacent counties in the Red River Valley of northwest Minne- sota. The greatest probability, 76%, occurred in six North Dakota counties; Rolette, Towner, and Cavalier along the Canadian border, and Traill, Steele, and Cass along the Red River near Fargo. The annual probability of a blizzard was 25% (1 yr in 4) to 50% across the remainder of Nebraska and Iowa, southeastern Wisconsin, western Kansas, central and eastern Colorado, eastern Wyoming, portions of Mon- tana, most of Maine, southern New Hampshire, and Gar- FIG. 3. Total area (km2) affected by blizzards each winter. rett County, Maryland. Annual probability of a blizzard

Unauthenticated | Downloaded 10/06/21 02:58 PM UTC 1JULY 2002 SCHWARTZ AND SCHMIDLIN 1769

FIG. 4. Annual probability of a blizzard by county, based on the frequency of blizzards during 1959/60 to 1999/2000. occurrence was 12% (1 yr in 8) to 25% in the northern preparations within the NWS of®ce and in communi- Sierra Nevada Mountains; the remainder of the northern cation of risks to state and county emergency managers. and central Rocky Mountains; central Kansas; most of Wisconsin; in the lake-effect snow regions of Michigan, d. Monthly blizzard frequency Ohio, , and New York; in western Mary- land and central Pennsylvania; and the remainder of Monthly frequency of blizzards (Fig. 5) peaked dur- New England. ing January in the blizzard zone and most other parts There are discontinuities in blizzard probabilities of the United States that experienced blizzards. How- along state boundaries that cannot be easily explained ever, blizzards were most frequent during December in climatologically. Sharp changes in blizzard probability the Sierra Nevada; during March in the central High across the Minnesota/Wisconsin border and North Da- Plains of western Nebraska, eastern Colorado, and Kan- kota/Montana border suggest historical differences in sas; and during April in Montana. The blizzard fre- reporting of blizzards between NWS of®ces with re- quency in western South Dakota showed a second peak sponsibilities on either side of those borders. The bliz- during April, matching the January peak frequency. zard patterns in Figs. 2 and 4 suggest that blizzards may There were few blizzards in October and they were be underreported in western Wisconsin, eastern Mon- limited to the northern and central Great Plains. A peak tana, and perhaps in other regions, also. Blizzard fre- October frequency of four blizzards occurred in south- quency may be underreported in this database for the ern Wyoming. Blizzard frequency increased in Novem- higher elevations of the western mountains, including ber with a maximum of 6±9 from eastern Colorado to the Cascades and Wasatch Range. northern Minnesota. November blizzards in the East An application of this blizzard climatology may be were limited to Maine, New Hampshire, western New seen in the annual probability of a blizzard within a York, and southern West where 1±2 occurred. NWS Forecast Of®ce (NWSFO) county warning area. Counties in the blizzard zone in the northern Great For example, the Grand Forks, North Dakota, NWSFO Plains had 10±18 December blizzards and blizzard fre- county warning area (CWA) encompasses 17 counties quency increased across the western and central United in eastern North Dakota and 18 counties in northwestern States. Blizzards were absent during December in most Minnesota. The 35 counties in this CWA reported 99 of the mid-Atlantic states and Appalachians. Blizzard blizzards during 1959±2000 for an average of 2.4 an- frequency showed a strong peak during January across nually. A blizzard occurred somewhere in the Grand the Midwest, Great Lakes, and Northeast, but then de- Forks CWA in 35 of the 41 winters in this study, giving creased in those regions during February. Blizzard ac- an empirical annual probability of 85% for a blizzard tivity during March shifted from the blizzard zone occurrence within the CWA. Ten blizzards occurred in southward into the central Great Plains where ``Colo- the Grand Forks CWA during 1996/97, the greatest of rado low'' cyclogenesis also peaks in March (Whittaker any winter during the study period. These annual prob- and Horn 1981). Much of the East had only one blizzard abilities and extremes could be used in training and in March (1993) and blizzards were absent during March

Unauthenticated | Downloaded 10/06/21 02:58 PM UTC 1770 JOURNAL OF CLIMATE VOLUME 15

FIG. 5. Number of blizzards recorded by county during the 41 winters 1959/60 to 1999/2000 for the months of (a) Oct, (b) Nov, (c) Dec, (d) Jan, (e) Feb, (f) Mar, (g) Apr, and (h) May.

Unauthenticated | Downloaded 10/06/21 02:58 PM UTC 1JULY 2002 SCHWARTZ AND SCHMIDLIN 1771 in southern Michigan, Indiana, and Illinois. April bliz- zard frequency was centered in the western Dakotas and was largely absent from the Great Lakes, Northeast (ex- cept New England), and the far western mountains. Bliz- zard conditions were rare during May. No county had more than one May blizzard during 1959±2000 and these were limited to portions of Colorado, Idaho, and Montana. Hare and Thomas (1979, p. 103) reported that bliz- zards on the Canadian prairies are most common in February and most likely in southwestern Saskatchewan and eastern Alberta, about 900 km west of the region of greatest frequency shown in this study. Stewart et al. (1995) reported that Canadian prairie blizzards were most common over southwestern Saskatchewan and FIG. 6. Population in counties affected by blizzards each winter. Wheaton (1998) wrote that ``Southern Saskatchewan is the blizzard capital of Canada.'' These comments further support our contention that blizzard frequency is un- f. Population in affected counties derestimated in Storm Data for northeastern Montana. The total population in counties affected by the 438 blizzards during 1959±2000 was 1 078 771 741, an av- erage of 26 311 506 per winter, and 2 462 949 per bliz- e. Blizzards and ENSO zard (Fig. 6). The smallest affected population was 741 people in the Clark County, Idaho, blizzard of February The annual number of blizzards and area affected by 1971. The largest number of people affected by a bliz- blizzards was compared to the ENSO teleconnection. zard was 72 864 107 in the March 1993 Superstorm in Correlations between seasonal ENSO phase and the the East. A linear regression of the population affected number of blizzards over the entire winter were weak each winter showed no signi®cant trend (slope ϭ 168 and marginally signi®cant for the October±December 646 people yrϪ1, p ϭ 0.63), in spite of an upward trend ENSO phase (r ϭϪ0.20, p ϭ 0.10) and the January± in the number of blizzards and a 39% increase in United March ENSO phase (r ϭϪ0.24, p ϭ 0.07). The neg- States population from 178 million in 1960 to 247 mil- ative correlation indicates blizzards are less likely with lion in 1990. This irony may be explained by the fact El NinÄa warm phase and more likely with the La NinÄo that the population in the blizzard zone of North Dakota, cold phase. When the ENSO phase was a moderate or South Dakota, and western Minnesota actually de- strong El NinÄo during October±December (n ϭ 9), the creased by 30 737 people between 1960 and 1990. So, mean number of blizzards that winter was 10.3, but although U.S. population increased during the period, when there was a moderate or strong La NinÄa (n ϭ 7), most of the increase was in the southern and western the mean number of blizzards was 12.7. The average states where blizzards were rare or did not occur. number of blizzards for a strong or moderate El NinÄo during January±March (n ϭ 8) was 10.0, while the av- 4. Summary erage was 13.6 blizzards when there was a moderate or strong La NinÄa during January±March (n ϭ 5). Al- This 41-yr county-level climatology of blizzards in though the relationship is weak, there tends to be 2±3 the conterminous United States was developed using more blizzards nationally during La NinÄa than El NinÄo Storm Data. There were 438 blizzards for an average winters. A regional focus on the blizzards that affected of 10.7 annually and an increasing linear trend in the number of blizzards. Blizzards annually affect an av- North Dakota or South Dakota showed no signi®cant erage of 26 million people over an area of 1.6 million relationship with October±December (r ϭϪ0.11, p ϭ km2. Regional patterns in the annual and monthly fre- 0.24) or January±March (r ϭϪ0.12, p ϭ 0.22) ENSO quencies of blizzards and the analyses of areas and pop- phases. Smith and O'Brien (2001) found regional pat- ulations affected by blizzards allow assessment of risk terns and seasonal (early, mid-, and late winter) patterns and vulnerability from this natural hazard. The database in the relationships between ENSO and snowfall in the could be used for more specialized analyses, such as United States. Further study on blizzards may reveal risk of a blizzard within NWSFO county warning areas, regional patterns with ENSO or other atmospheric te- within emergency management districts, within water- leconnections. The weak relationships found here be- sheds, along transportation corridors, and so on. Further tween blizzards and ENSO should not be used to attri- studies on regional patterns in blizzard frequency and bute the occurrence of any particular blizzard to ENSO trends and associations with other atmospheric telecon- (see also Barsugli et al. 1999). nections will help in understanding these dangerous and

Unauthenticated | Downloaded 10/06/21 02:58 PM UTC 1772 JOURNAL OF CLIMATE VOLUME 15 costly storms. Efforts should be made to ensure the high Fredston, J., and D. Fesler, 1994: Snow Sense: A Guide to Evaluating quality and consistency of Storm Data to maintain a Snow Avalanche Hazard. 4th ed. Mountain Safety Center, 116 pp. reliable record of storms and their effects in the United Fujita, T. T., 1987: U.S. tornadoes, part 1, 70-year statistics. Satellite States. and Mesometeorology Research Project Res. Paper 218, Uni- versity of Chicago, 122 pp. Acknowledgments. Appreciation is extended to the Gaf®n, D. M., and D. G. Hotz, 2000: A precipitation and ¯ood cli- matology with synoptic features of heavy rainfall across the National Weather Service of®ce in Cleveland for use of southern Appalachian Mountains. Natl. Wea. Dig., 24, 3±15. their archives for early issues of Storm Data and to Graff, J. V., and J. H. Strub, 1975: The Great Upper Plains blizzard Patrick Francis for assistance with ArcView. This re- of January 1975. Weatherwise, 28, 66±69, 83. search was completed with a University Fellowship Haines, D. A., 1966: The late March blizzard of 1966 in the Middle West. Weatherwise, 19, 194±197. awarded to Robert Schwartz at Kent State University. Hare, F. K., and M. K. Thomas, 1979: Climate Canada. 2d ed. John Appreciation is extended to Connie McOmber of Car- Wiley and Sons, 230 pp. tographic Services, Department of Geography, Ball Helburn, N., 1982: Severe winter storms as natural hazards. Great State University, for assistance with the graphics. Plains±Rocky Mountain Geogr. J., 10, 86±95. Kocin, P. J., and L. W. Uccellini, 1990: Snowstorms along the North- eastern Coast of the United States: 1955 to 1985. Meteor. Mon- REFERENCES ogr., No. 44, Amer. Meteor. Soc., 280 pp. Lopez, R. E., R. L. Holle, and T. A. Heitkamp, 1995: Lightning casualties and property damage in Colorado from 1950 to 1991 Babin, G., 1975: Blizzard of 1975 in . Weatherwise, based on Storm Data. Wea. Forecasting, 10, 114±126. 28, 70±75. Lott, N., T. Ross, and M. Sittel, 1996: The winter of '95±'96: A Barry, R. G., 1992: Mountain Weather and Climate. 2d ed. Routledge, season of extremes. National Climatic Data Center, Tech. Rep. 402 pp. 96-02, Asheville, NC, 15 pp. Barsugli, J. J., J. S. Whitaker, A. F. Loughe, P. D. Sardeshmukh, and Ludlum, D. M., 1968: Early American Winters II 1821±1870. His- Z. Toth, 1999: The effect of the 1997/98 El NinÄo on individual torical Monogr., Amer. Meteor. Soc., 257 pp. large-scale weather events. Bull. Amer. Meteor. Soc., 80, 1399± McKay, G. A., 1981: Snow and living things. Handbook of Snow: 1411. Principles, Practices, Management, and Use, D. M. Gray and Black, R. E., 1971: A synoptic climatology of blizzards on the north- D. H. Male, Eds., Pergamon Press, 3±31. central Plains of the United States. NOAA Tech. Memo. NWS North, G. R., Ed.,1996: Glossary. Encyclopedia of Weather and Cli- CR-39, 38 pp. mate, S. H. Schneider, Ed., Vol. 2, Oxford University Press, 853± Branick, M. L., 1997: A climatology of signi®cant winter-type weath- 874. er events in the , 1982±94. Wea. Fore- Rooney, J. F., Jr., 1967: The urban snow hazard in the United States: casting, 12, 193±199. An appraisal of disruption. Geogr. Rev., 57, 538±559. Brooks, H., and C. A. Doswell III, 2001: Some aspects of the inter- Salmon, E. M., and P. J. Smith, 1980: A synoptic analysis of the 25± national climatology of tornadoes by damage classi®cation. At- 26 January 1978 blizzard cyclone in the . mos. Res., 56, 191±201. Bull. Amer. Meteor. Soc., 61, 453±460. Burrows, W. R., R. A. Treidl, and R. G. Lawford, 1979: The southern Schwartz, R. M., 2001: Geography of blizzards in the conterminous blizzard of January 26 and 27, 1978. Atmos.±Ocean, 17, United States, 1959±2000. Ph.D. dissertation, Kent State Uni- 306±320. versity, Kent, OH, 176 pp. Changnon, S. A., Jr., and D. Changnon, 1978: Winter storms and the Scott, R. C., 1996: Introduction to Physical Geography. West Pub- record-breaking winter in Illinois. Weatherwise, 31, 218±225. lishing, 560 pp. Cohen, J., 1996: Snowstorms. Encyclopedia of Weather and Climate, Smith, S. R., and J. J. O'Brien, 2001: Regional snowfall distributions S. H. Schneider, Ed., Vol. 2, Oxford University Press, 700±703. associated with ENSO: Implications for seasonal forecasting. Conner, W. C., K. C. Crawford, and E. L. Hill, 1973: Snow forecasting Bull. Amer. Meteor. Soc., 82, 1179±1191. in the South: Occasional blizzards over the southern Plains to Steppuhn, H., 1981: Snow and agriculture. Handbook of Snow: Prin- rare Gulf Coast . Weatherwise, 26, 244±248. ciples, Practices, Management, and Use, D. M. Gray and D. H. CPC, cited 1999: Cold and warm episodes by season. [Available online Male, Eds., Pergamon Press, 60±125. at http://www.cpc.noaa.gov/products/analysis࿞monitoring/ensostuff/ Stewart, R. E., and Coauthors, 1995: Winter storms over Canada. ensoyears.html.] Atmos.±Ocean, 33, 223±247. Curran, E. B., R. L. Holle, and R. E. Lopez, 2000: Lightning casualties Stommel, H. G., 1966: The Great Blizzard of '66 on the Northern and damages in the United States from 1959 to 1994. J. Climate, Great Plains. Weatherwise, 19, 189±193, 207. 13, 3448±3464. U.S. Census Bureau, cited 2001: County population estimates. [Avail- DeGaetano, A. T., T. S. Schmidlin, and D. S. Wilks, 1997: Evaluation able online at http://www.census.gov/population/www/estimates/ of East Coast snow loads following January 1996 storms. J. countypop.html.] Perform. Constr. Facil., 11, 90±94. Wheaton, E., 1998: But It's a Dry Cold. Fifth House, 185 pp. Dewey, K. F., 1977: Lake-effect snowstorms and the record breaking Whittaker, L. M., and L. H. Horn, 1981: Geographical and seasonal 1976±77 snowfall to the lee of Lakes Erie and Ontario. Weath- distribution of North American cyclogenesis, 1958±1977. Mon. erwise, 30, 228±231. Wea. Rev., 109, 2312±2322. Fox, R. L., 1952: Blizzards of the Northern Plains. Weatherwise, 5, Wild, R., 1997: Historical review on the origin and de®nition of the 123±126, 132. word blizzard. J. Meteor., 22, 331±340.

Unauthenticated | Downloaded 10/06/21 02:58 PM UTC