The potential for moderate to occasionally heavy rainfall remains in the forecast for later today and tonight as a cold front will become draped across the state from the southwest to northeast. This boundary will approximately be located near the I-44 corridor of the state. Locations near this boundary will have the greatest chance for some multi-inch rainfall over the next 48 hours that may result in localized flash flooding in some locations. For this reason, the National Weather Service ( NWS) has issued flash flood watches for a number of counties across northeastern and central OK remaining in effect through Wednesday evening. At this point, only a few counties across east-central are included in the watch.
The upper air pattern reflects a trough of low pressure located across the Midwest into southeastern Canada and a mid-level ridge to the west. A weak disturbance located to our west this morning should move across the state today and tonight aiding in the development of rain and storms. Most model data depict a surface wave (small area of low pressure) developing along the front later tonight and moving northeast into central and northeastern OK early Wednesday morning to midday. This wave should result in heavy rainfall for part of northeastern OK later tonight into early Wednesday. The surface boundary is expected to remain near the state Wednesday night but should retreat northward as a warm front sometime early Thursday. After the early Thursday morning hours, most of the rain and storm activity should also migrate northward away from the state and a mid-level ridge of high pressure will begin to develop over the southern plains. This will bring hot and muggy conditions back to Oklahoma Friday into the weekend. Most data also suggest this ridge will retrograde (move westward) early next week with another northwest flow aloft pattern developing sometime next week. This highly unusual pattern for July could bring additional rain and storm chances back to part of Oklahoma by the middle of next week. But at this point, the pops will remain out of the forecast for early next week.
Severe weather threats today and tomorrow remain very low regarding large hail or damaging winds. It appears our main threats will remain confined to heavy rainfall and some localized flooding. Model output suggests that some locations will receive from 2 to 5 inches of rainfall across part of the watch area with outlier totals from 4 to 6 inches. There’s a very small chance of small area to receive even higher amounts. Rain located to our west this morning will expand during the next few hours with rain becoming likely for most of the flood watch area by late morning to afternoon. We may get a small break later this afternoon before more heavy rainfall is likely to develop tonight and continue through the first half of Wednesday.
Temperatures along and north of the boundary will be a treat for early July. Most locations will reside in the upper 70s near 80. A few locations across extreme northwestern OK could stay in the upper 60s for daytime highs today. The Tulsa metro should expect highs today in the upper 70s with Wednesday afternoon highs near 78 to 83. Wind speeds will remain in the 8 to15 mph range but could be variable in direction with locations northwest of I-44 experiencing northwest winds while locations south of I-44 with southeast or east winds.
Temperatures Thursday will rebound to near 90 with readings this weekend from morning lows in the mid-70s to daytime highs nearing 96. Very humid conditions are likely to remain this weekend with temperature heat index values near 100 to 104.
Thanks for reading the Tuesday morning weather discussion and blog.
Have a super great day!