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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 show moderate to high surface based
                        CAPE from 2500 to 3500 j/kg.

                        The Denver sounding from 12 UTC June 15 had a loaded gun appearance with rich moisture up to 700mb. With surface
                        heating, strong instability would be present.

                        On June 15, 1965 , a tornado was observed by a weather research team at Colorado State University. A major hail storm
                        occurred in the northern suburbs of Las Vegas, NM and Sapello, NM with hail up to 3" in diameter. The 19 UTC surface
                        chart showed 2 areas of moist upslope flow--one in New Mexico and ther other in northeast Colorado back to the front range.
                         The Denver sounding from 12 UTC June 15 had a loaded gun appearance with rich moisture up to 700mb. With surface
                         heating, strong instability would be present.

                       
                         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 Aardmore but the theta-e was slightly higher at Aardmore.

                   The Denver sounding from 12 UTC June 15 had a loaded gun appearance with rich moisture up to 700mb. With surface
                        heating, strong instability would be present.
    

                        On June 16, 1965 several tornadoes occurred along and west of the urban corridor in Colorado. On this day, hail golfball
                        size and greater occurred at Holman, NM (elev. 7800ft) which is 32 miles northwest of Las Vegas in the foothills on the         
                        southern Rockies.  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). The 500mb charts at
                        12Z and 00Z showed southerly flow up and down the western high plains.  Even though COS and Vichy(VIH) had about the
                        same T/TD, the theta-e was much higher at COS owing to a MUCH larger 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.
                        Here is an terrain map with a depiction of the strong upslope on the windward side of Pikes Peak and the training of storms
                        to the N/NNE that lead to 12 to 14" rain amounts in Larkspur, Palmer Lake and south of Castle Rock. Creeks in the region
                        flooded and caused major flooding in Denver with $250,000,000 damage.