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<br />numbers used in table 2.2 are the same as those in table 2.1, and are therefore <br />not sequential. <br /> <br />Table 2.2 provides the name of a city or town nearest the storm center, date of <br />the storm, latitude and longitude, elevation, and I,OOO-mi2 24-hr and 10-mi2 6-hr <br />observed precipitation amounts. Preci-pitation values are given to provide some <br />indication of the magnitude of the storm selected. For a few storms, no data are <br />available for these specific area sizes and durations. Dashes are shown in the <br />table for these storms. The elevations given in table 2.2 are not actual <br />elevations at the location of the storm center, but are read from the <br />barrier/effective elevation analysis (chapt. 3). When a barrier occurs upwind of <br />the storm location, it is noted in table 2.2 by the letter "B" after the <br />elevation. <br /> <br />2.4, Meteorological Analyses of Storms <br /> <br />The storms wi thin this region can be grouped into two separate categories: <br />(1) those associated with extratropical cyclones or extratropical convective <br />activity and (2) those that are either the direct result of tropical cyclones or <br />have as a primary moisture source the remnants of tropical cyclones that have <br />crossed the Texas coast. In this section, the weather situation associated with <br />some of the more important general storms will be discussed. The meteorological <br />analyses of these and other major storms form the basis for the storm <br />classification system described in section 2.5. The meteorological situations <br />associated with local storms is discussed in Chapter 12. <br /> <br />2.4.1 Extratroplcal Storms <br /> <br />There are nine extratropical storms that are considered most important in the <br />development of the PMP for the CD-103 region. The meteorological situation <br />associated with each of these storms is discussed in this section. <br /> <br />2.4.1.1 Warrick, Montana June 6-8, 1906 (10). During the period <br />June 6-8, 1906, extensive rainfall occurred over most of Montana and western <br />North Dakota, causing flooding with extensive damage to agricultural interests. <br />At Warrick, MT (480 04'N, 1090 39'W, elevation 4700), a total of 13.3 in. of rain <br />was recorded during a 54-hr period beginning at 1 :00 a.m. on June 6, and ending <br />at 7:00 a.m. on June 8. On the morning of June 7, the heaviest rainfall <br />occurred, 5.3 in. in a 6-hr period. Synoptic weather charts for 0600 MST (all <br />times referred to in this report will be Mountain Standard Time) for the period <br />June 4-8, 1906, are shown in figure 2.2. On the morning of June 4, a weak low <br />pressure system was centered in western Canada, just north of Montana. A cold <br />front extended southward through the United States toward the southern part of <br />Nevada. As this Canadian low pressure system continued to move eastward, a weak <br />Low formed on the Nevada-Utah border. This Low moved northeastward to east- <br />central Montana. By the morning of June 6 it had split, and one Low was located <br />over the Canada-Montana border at about 1050W, and a second Low was over the <br />Wyoming-South Dakota border in the vicinity of Rapid City. A warm front extended <br />almost due eastward from this second Low toward the Great Lakes. The cold front <br />from that Low extended south and then southwestward through Nebraska, eastern <br />Colorado, central New Mexico, into Arizona. General rains fell north of the warm <br />front and extended westward from the Low well past the Continental Divide. Ahead <br />of the cold front, southerly flow brought warm moist air from the Gulf of Mexico <br />up through the Midwest and into the northern tier of states. This warm moist air <br /> <br />17 <br />