Forecasts are leaning more and more towards a significant outbreak of severe weather, including violent and potentially long-lived tornadoes and very large, destructive hail, across central and northeastern Oklahoma later this afternoon, beginning around 4 pm and lasting until at least 8 pm. This includes the Oklahoma City metro area and areas that were hit with strong tornadoes in last week’s outbreak. Please do not panic! Be prepared, have plan of action now, and be ready to enact your plan once severe weather strikes. The best place to be during a violent tornado is underground. If you have a storm shelter or know of one nearby, you are best to utilize it.
Why is this happening? With partly to mostly cloudy skies, the sun has been able to induce surface heating; we have temperatures in the mid-to-upper-80s across these regions currently. Moisture in the lower levels of the atmosphere has increased. Dewpoint temperatures are currently in the 70s across all of central and eastern Oklahoma. The CAP, which refers to warmer temperatures above the surface that prohibit rising motion and thus thunderstorm development, is vanishing. A surface low in southwest Oklahoma and a dry line in western Oklahoma are the final pieces to the puzzle to complete all the ingredients necessary for dangerous supercell thunderstorms. Again, we are strongly urging you to take action now. A Particularly Dangerous Situation (PDS) TORNADO WATCH has been issued for central and northeast Oklahoma until 12 AM CDT. This is more serious than a regular tornado watch. This means that violent tornadoes are of high concern. In addition to tornadoes, very large, destructive hail is also of great concern. The watch indicates that hail may be up to 4 inches in diameter and that damaging wind gusts may reach 80 mph. Flash flooding is also possible, and a FLASH FLOOD WATCH is still in effect through Saturday morning for central and eastern Oklahoma. Over 2 inches of rain is possible in some areas through Saturday morning, so we urge you to be alert now, especially those residents involved in clean-up efforts from last week’s tornadoes.
Please scroll down to see much more, including maps and radars and a synopsis on what is to come.
Oklahoma Severe Weather/Flood Advisories
Oklahoma City (TLX) Radar
Tulsa (INX) Radar
Today/Tonight
With partly to mostly cloudy skies across the state, the sun has the opportunity to peek out through the clouds at times to heat the surface and cause the severe threat to be even more dangerous. Highs today will be in the low-to mid-90s across western Oklahoma, but in southwest Oklahoma, highs will be in the upper-90s to low-100s. In central Oklahoma, highs will be in the upper-80s to low-90s today. In eastern Oklahoma, we will have highs in the mid-to-upper-80s. Winds in southwestern, central, and eastern Oklahoma will be sustained between 15 and 25 mph, blowing from the south-southwest, and gusting as high as 30 mph. In northwestern Oklahoma, including the panhandle, a north wind will blow around 5 to 10 mph.The Storm Prediction Center has outlined a moderate risk stretching from central to northeast Oklahoma and including the state’s two most populated cities: Oklahoma City and Tulsa. A slight risk surrounding this moderate risk encompasses all of central and eastern Oklahoma. The National Weather Service in Norman, OK has provided a plethora of graphics detailing today’s severe weather threat. Again, isolated supercell storms will fire up in the afternoon, but the main timing for severe weather is a little later in the day due to the CAP in place earlier today. Storm initiation may also begin a little farther west this afternoon, with storms firing up in northwest Texas and southwest Oklahoma just east of Altus. We expect the storms to initiate around 3 pm, with the threats being very large hail up to softball size, damaging wind gusts to 75 mph, and tornadoes, occurring around 4 pm to 6 pm in central Oklahoma just north of Oklahoma City, from north of Lawton to Ponca City, and in northeastern Oklahoma. For the early evening, from 6 pm to 10 pm, the Oklahoma City metro area is right in the middle of the highlighted (red) area for greatest risk for severe weather, including tornadoes, some of which could be violent. Additional threats are very large hail up to softball size and damaging wind gusts up to 75 mph. The yellow shaded area on the graphic above may also see tornadoes, but the threat is lower. All shaded areas should still be prepared for severe thunderstorms. For the late evening, past 10 pm, the tornado threat should diminish, but all of central and eastern Oklahoma are at danger for flooding problems, some large hail, and damaging winds. The severe weather threat will last through at least midnight and could last through the overnight hours into Saturday morning. Even if storms lose severe characteristics, heavy rain is still a concern overnight in central and eastern Oklahoma, which makes flooding a high concern at this point. According to the current rainfall forecast, areas in north central Oklahoma could see 2 to 3 inches of rain.
THREATS:
Very large hail up to softball size
Damaging wind gusts to 75 mph
Tornadoes, perhaps violent
Heavy rainfall
Saturday/Saturday Night
As we mentioned above, Friday’s severe storms could last through the overnight hours into Saturday morning, so central Oklahoma but especially eastern Oklahoma will need to be on the lookout for additional showers and thunderstorms through noon Saturday. By the afternoon, the storms should finally come to an end except for southeastern Oklahoma. The Storm Prediction Center has southeastern Oklahoma in a slight risk for severe weather on Saturday. Severe thunderstorms affecting this region will fire up in the afternoon hours, posing threats of large hail, damaging winds, and even tornadoes, though the tornado threat is lower at this time. Again, this severe weather threat on Saturday afternoon is only for southeastern Oklahoma. Skies will gradually start to clear in central and northeastern Oklahoma. Due to the passage of the cold front, highs will be much cooler across the state. In the northern half of Oklahoma, highs will be in the upper-70s to low-80s. In the southern half of Oklahoma, highs will be in the mid-to-upper-80s. This may not seem that “cool” but after a day in the 90s and possibly 100s on Friday, this should be a refreshing change.
On Saturday night, far southeastern Oklahoma will continue to see thunderstorms, some of which will be severe early in the evening, while the rest of the state remains dry and has mostly clear to partly cloudy skies. Note that low temperatures will be significantly cooler. Due to cloud cover for the past few nights, we have been used to mild lows in the 60s and 70s. Well, this will change with the passage of the cold front and clearing skies. Expect the warmest lows to be in the 60s in far southeastern Oklahoma while the rest of the state has lows in the low-to-upper-50s. Some 40s may even invade the panhandle!
THREATS (SE OK):
Large hail
Damaging winds
Isolated tornadoes
Heavy rainfall
Sunday/Sunday Night
If you are tired of severe weather and just want a day of sunshine, then Sunday will be your day. All of Oklahoma is in the clear for severe weather, and skies will be sunny to partly cloudy throughout the entire day. While high temperatures warm somewhat in the west, they will become even cooler in the east. In eastern Oklahoma, expect to see highs only in the mid-to-upper-70s. In central Oklahoma, highs will be in the upper-70s to low-80s. Farther towards the west, we will have highs in the low-to-mid-80s.
Sunday night will also bring clear to partly cloudy skies across the state, with lows coolest this time in northeastern Oklahoma, dropping down to the low-to-mid-50s. Elsewhere, we will have lows mainly in the mid-to-upper-50s but some 60s across western Oklahoma and far southern Oklahoma are possible.
Resources
Storm Prediction Center
National Weather Service Amarillo, TX
National Weather Service Norman, OK
National Weather Service Tulsa, OK
MORE: Moore EF5 Tornado: Information and Resources
Are you confused by the terms “slight risk,” “moderate risk,” and “high risk” that are used by the Storm Prediction Center? For more information on what a slight risk is, please click HERE. For more information on what moderate and high risks are, please click HERE. These graphics and information have been provided by the National Weather Service Office in Norman, OK and are available on their Facebook page.
Storm Reports
Wednesday, May 29
Thursday, May 30
Wednesday and Thursday, May 29 & 30
Sources: NWS, SPC, HOOT, Mesonet, livestormchasing.com (photo)
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