June 14

                        Late on June 13 and early on June 14, 1965, low level upslope flow pushed moisture onto the front range. Two frontal
                        boundaries were present by the 22 UTC June 14. The northern front extended from southern Colorado across Oklahoma
                        and Arkansas. The southern front extended up and down the front range into New Mexico and Texas. Very unstable
                        conditions existed along the length of the front range, with the highest instability further north in Colorado and Wyoming.
                        The 00z June 15  500mb chart showed a deep trough in the western US with moderate mid level flow as far east as
                        the front range of Colorado. The 6km flow (close to 400mb at Denver) was 40kts, which is fairly strong by eastern
                        Colorado standards in mid June. It was fairly cold aloft for mid June with 400mb temperatures from -22 to -24C and
                        300mb temps from -38C to -40C. 700mb temps were 15C at Albuquerque,  +13C at Denver and slightly cooler further
                        north in Wyoming. Approximate soundings for Douglas, WY and Fort Collins, CO showed moderate to high surface based
                        CAPE from 2300 to 2800 j/kg. Tornadoes occurred 3 to 5 miles west of Loveland and southeast of Douglas, WY. 
                        The surface observation form Fort Collins makes reference to the tornado that occurred west of Loveland that lasted
                        for 15 minutes. The capping inversion was obviously much weaker in the foothills and mountains southwest of Fort Collins
                        where the storm developed. The storm probably initiated on the edge of the mountains west or southwest of Loveland.
                        Given the sw to wsw mid level flow,  the storm probably moved to the ene or east.

                         Tornadoes also occurred near Douglas, WY and at Colorado Springs. Baseball sized hail fell in Colorado Springs. The
                        tornado occurred at Peterson Field in Colorado Springs.

                        The other upper air charts are:    850mb    200mb                      

                        The theta-e was higher at Las Vegas than at Chanute, even though the T/TD were 4F/19F higher at Chanute. This is because               
                        elevated heating resulted in a potential temperature of 108F at Las Vegas. This offsets the moisture deficit at Las Vegas.
                        The highest theta-e was at Colorado Springs where the T/TD were 11F and 13F lower than at Mcalester, OK.                       

                        
                        On June 15, 1965 , a tornado was observed by a weather research team at Colorado State University. The surface
                        observation sheet from Fort Collins indicated that a weather research team witnessed a tornado 8 miles west of Fort
                        Collins at 413 pm.

                        A major hailstorm occurred in the northern suburbs of Las Vegas, NM and Sapello, NM with hail up to 3" in diameter. A
                        tornado occurred 32 miles west of Cheyenne (elev. 8200ft) or about 15 miles southeast of Laramie, tearing up some timber,
                        but hitting no structures. Another tornado occurred 25 miles west of Cheyenne.

                        A tornado destroyed thousands of valuable trees at the Dick Hornbuckle ranch 40 miles north of Gillette, WY. Some of these
                        trees were ancient and 5 feet in diameter. Two trailer houses were demolished. A man suffered broken ribs. Baseball sized
                        hail remained until the next day. Tangled masses of downed trees were all that remained of these trees that served as a winter
                        cattle shelter for years.

                        The 19 UTC surface chart showed 2 areas of moist upslope flow--one in New Mexico and the other in northeast Colorado
                        back to the front range.   

                        The approximate sounding for Las Vegas, NM for 21 UTC showed 2500 j/kg CAPE, with a freezing level of 8400 ft AGL
                        and web-bulb zero height of  6000 ft AGL.           

                        The T/TD were 18F and 13F higher at Tulsa compared to Las Vegas but the theta-e was slightly higher at Las Vegas. The
                        T/TD were 9F/12F lower at Denver compared to Ardmore but the theta-e was slightly higher at Denver. The potential
                        temperature at Santa Fe was 111F. This makes up for the lack of moisture(mixing ratio 9.5 g/kg) as the theta-e was higher than
                        at Tulsa (T/TD of 84F/66F).  So even though the mixing ratio was 47% lower at Santa Fe, and the temperature 8F lower
                        than at Tulsa, the theta-e was actually higher at Santa Fe since the potential temperature was 111F.

                   Very strong upslope flow on the 16th resulted in very high surface dewoints along the front range from Las Vegas, NM
                        to Pueblo and Colorado Springs.  On June 16, 1965 several tornadoes occurred along and west of the urban corridor in
                        Colorado. On this day, hail to golfball size and greater occurred at Holman, NM (elev. 7800ft) which is 32 miles northwest
                        of Las Vegas in the foothills of the southern Rockies. Hail to 1.5" fell at Black Lake NM (elev. 8600 ft).  I plotted the
                        20 UTC surface observations on a terrain map as well.

                        The 20 UTC surface map showed strong southeast winds advecting moisture onto the front range. The T/TD at Colorado
                        Springs(elevation 6180 ft.) were 64F/60F. At Dallas the dewpoint was 70F. But since a 60F dewpoint at COS has the same
                        amount of moisture as a 66F dewpoint at Dallas, the mixing ratio at Fort Worth was only 16% higher than at COS. The
                        surface temperature at Dallas was 85F compared to 64F at Colorado Springs. However, the potential temperature was
                        much higher at Colorado Springs--96.9F versus 85.8F. Therefore, the surface theta-e was higher at COS(351.6K versus
                        350.8K). Even though COS and Vichy(VIH) had about the same T/TD, the theta-e was much higher at COS owing to a
                        MUCH higher potential temperature and somewhat higher mixing ratio. The theta-e at COS was also higher than at Dodge
                        City, mostly due to the huge difference in potential temperature.