Weather made history in Oklahoma in 2015, which ended with a powerful winter storm that blanketed the state, said state climatologist Gary McManus of the Oklahoma Climatological Survey.
The December 26-28 storm prompted blizzard, ice storm and winter storm warnings for western Oklahoma while the eastern half was awash in flood-related emergencies. High winds accompanied the storm throughout its stay. The Oklahoma Mesonet recorded 984 wind gusts of at least 50 mph from 10 p.m. on December 26 through 4:15 a.m. on Dec. 28. Those high winds, gusting to more than 70 mph at times, combined with freezing rain and ice to leave more than 200,000 without power.
The Oklahoma Department of Emergency Management (OEM) reported a preliminary count of five people having died as a result of the severe weather, with an additional 104 storm-related injuries.
The Oklahoma Highway Patrol (OHP) reported 955 weather-related collisions, including 137 injury collisions, according to OEM. The OHP provided 39 motorist assists, including water rescues. The Stranded Motorist Assistance Recovery Teams assisted approximately 170 motorists from December 26-29.
Flooding was the main concern across eastern Oklahoma where 6-12 inches fell over the three-day period. Numerous roads were closed due to flooding, and floodwaters from dams in northeast Oklahoma led to evacuation warnings.
Widespread catastrophic damage was reported along the Illinois River basin as the river reached record flood levels. The river crested at 30.69 feet near Tahlequah on December 28, besting the previous record from that location of 27.94 feet on May 10, 1950.
Numerous tornado warnings were issued in central and eastern Oklahoma on the 26th and several instances of large hail were reported. Preliminary reports indicate possible twister touchdowns just to the southeast of the Oklahoma City metro area, yet to be confirmed by the National Weather Service (NWS). A total of 109 tornadoes were reported in Oklahoma during 2015. That’s the third highest annual total since accurate records began in 1950. Two deaths and 55 injured were attributed to tornadoes during 2015.
December ended as the wettest on record for the state according to preliminary statistics from the Oklahoma Mesonet. The statewide average precipitation for the month was 5.92 inches, 3.86 inches above normal. The previous record of 4.87 inches was set back in 1984. Those records date back to 1895.
Mt. Herman led the Mesonet with 16.68 inches for the month, and 30 of the Mesonet’s 120 stations recorded at least 10 inches of rainfall. The highest total ever recorded during December was 18.13 inches from the NWS cooperative observing site at Bear Mountain Tower back in 1971. Mt. Herman’s total ranks as the fifth highest December total on record for the state. The far western Panhandle stations of Kenton and Boise City were the only locations to record less than an inch of precipitation with the former having the lowest total at 0.58 inches. Boise City reported 8 inches of snow for the month to bring their seasonal total to 16 inches, the highest in the state.
The second wettest November and wettest December on record gave 2015 a final push past the previous wettest calendar year by half a foot with a preliminary statewide average of 53.88 inches. The record prior to 2015 was held by 1957 at 47.88 inches.
“The new record obviously came with some equally monumental localized totals,” McManus said. “The NWS cooperative observing station at Daisy in Atoka County blasted past the previous record for wettest calendar year at any location in the state with 89.69 inches, topping Tuskahoma’s 88.27 inches in 1990.”
May captured the record for wettest month in Oklahoma history with a statewide average of 14.44 inches, topping October 1941’s 10.75 inches.
December ended much warmer than normal despite the late-month cool down. According to preliminary data from the Oklahoma Mesonet, the statewide average temperature was 44.5 degrees, 5.6 degrees above normal to rank as the fourth warmest on record.
The year finished quite warm with a statewide average of 61 degrees, 1.1 degrees above normal. That ranks the year as the 17th warmest on record. The Buffalo and Freedom Mesonet sites reached 108 degrees to earn the year’s highest readings. The lowest temperature of minus 6 degrees was recorded at Boise City back on January 4. The Okmulgee Mesonet site recorded a heat index of 118 degrees to earn top prize in that category.
Oklahoma started 2015 with 59 percent of the state in drought according to the U.S. Drought Monitor, and peaked in early April at 68 percent. The dry conditions were eradicated by the heavy rains of November and December.
“The NWS’ Climate Prediction Center (CPC) expects the El Niño that is thought to have impacted both our spring and late fall-early winter weather to remain strong through winter before dissipating during the spring or early summer of 2016,” McManus said.
With that as the backdrop, CPC outlooks call for increased odds of above normal precipitation across southwestern Oklahoma and the Panhandle during January. In the longer term, they see increased odds for above normal precipitation across most of Oklahoma through mid-spring, with greater chances across the western half of the state. There are no clear indications in the outlooks for temperature.”