Mother Nature turned off the spigot and cranked up the heat during the first 10 days of June, allowing swollen streams, rivers and reservoirs to slowly recede after the record May rains. The respite was short-lived, however, thanks to a tropical invasion from both the Pacific and Atlantic. First up was the remnant of hurricane Blanco from the Pacific that interacted with a stalled front and dumped 2-4 inches of rain over a wide swath of the state, including more than 10 inches near Hollis in far southwestern Oklahoma. Almost directly thereafter, the Gulf of Mexico offered up the remnant of tropical Storm Bill. That storm moved slowly to the north from the Texas Gulf Coast as it pumped moisture-laden Gulf air into the Southern Plains and Oklahoma. The state saw several rounds of rain before Bill, at that point downgraded to a tropical depression, actually arrived. The system slowed down and camped over south central Oklahoma. Totals of 6-12 inches were common from the Lake Texoma area up through central Oklahoma. Lesser totals of 2-4 inches occurred to the north and east as Bill eventually sped its way out of the state. The added moisture created widespread flooding once again. Lake Texoma, which had water surge over its spillway for only the fourth time in its history back in May, upped that count to five following Bill. A portion of I-35 in the Arbuckle Mountains was closed for several days due to a rockslide. Water nearly topped the bridge between Oklahoma and Texas when the Red River hit a historic crest of more than 42 feet. At least three deaths were attributed to the flooding, including the loss of a 2-year-old boy who was swept from his father's arms in floodwaters near Ardmore.
Thanks to the boost from the tropical systems, the statewide average precipitation total as measured by the Oklahoma Mesonet was 5.04 inches, 0.52 inches above normal and the 33rd wettest June since records began in 1895. That total would not accurately describe the precipitation pattern across the state, however. South central Oklahoma had an average of 10.13 inches, 5.40 inches above normal to rank as its third wettest June on record. In contrast, north central Oklahoma received an average of 2.45 inches, over 2 inches below normal to rank as the 31st driest. Newport led all Mesonet sites with 15.07 inches while the Panhandle location of Boise City recorded the lowest total of 1.03 inches. The National Weather Service (NWS) observing site at Ardmore recorded 16.83 inches for its wettest June on record, dating back to 1901. Healdton did the same with 15.48 inches dating back to 1894. The January-June statewide average came in at 28.73 inches, nearly 10 inches above normal and the second wettest first six months of the year on record. Only 1957's 32.69 inches stands higher. For southwestern and south central Oklahoma, it was the wettest on record at 12.04 inches and 20.10 inches above normal, respectively. Oklahoma City recorded 5.77 inches during June to bring its January-June total to 34.43 inches. That tops 1908's total of 33.23 inches as the wettest such period on record.
The statewide average temperature for June was 78.2 degrees, 1.7 degrees above normal and ranked as the 33rd warmest June on record. Altus and Grandfield reached 101 degrees on June 10 while Boise City matched that high on the 22nd for the highest temperature of the month. Several stations recorded 51 degrees on June 1 for the lowest reading. The January-June statewide average stayed just below normal at 55.6 degrees, the 54th warmest such period on record.
The number of confirmed tornadoes during 2015 stood at 75 through June according to NWS data, although there were no reports during June. The total for May rose to 67. The Mesonet site at Minco recorded a wind gust of 96 mph on the 29th associated with a severe thunderstorm.
The July outlooks from the NWS' Climate Prediction Center indicate increased odds of above normal precipitation and below normal temperatures. Accordingly, CPC does not forecast any drought development in the state through the end of July.