textproduct: Norman

KEY MESSAGES

Updated at 249 PM CDT Tue Sep 29 2026

- Periods of heavy rain are expected from Wednesday afternoon through Thursday afternoon, with flooding possible in parts of western north Texas and southern Oklahoma.

- Chance of severe storms Wednesday afternoon and Wednesday night.

- Significant cooldown expected from Thursday through the weekend.

NEAR TERM

(Rest of today and tonight) Issued at 249 PM CDT Tue Sep 29 2026

An area of rain continues to lift to the northeast across the northwest half of Oklahoma today. The coverage of rain should decrease this evening as the aforementioned wave exits the area. However, lingering showers and thunderstorms may persist across northwest Oklahoma. Cloud cover/reduced insolation associated with the rain shield is resulting in a northwest to southeast temperature gradient this afternoon. Temperatures range from the mid 70s across northwest Oklahoma to the low 90s across southeast Oklahoma. For tonight, most locations should remain dry with rain chances generally confined across far northwest Oklahoma.

Mahale

SHORT TERM

(Wednesday through Thursday night) Issued at 249 PM CDT Tue Sep 29 2026

Wednesday into Thursday will be the most active period over the next week as an upper-level low and the remnants of Hurricane Polo merge and approach the Southern Plains.

There will likely be a relative lull in the coverage of rainfall Wednesday morning with perhaps some scattered showers across western Oklahoma and western north Texas. However, most locations will likely remain dry in the morning.

Synoptic-scale ascent will increase as the consolidated upper- level system approaches from the west Wednesday afternoon in tandem with a surface low and a trailing dryline in the Texas/Oklahoma panhandles. Increasing instability (MLCAPE ~1000 to 1500 J/kg) ahead of the dryline will result in an environment capable of producing strong to severe thunderstorms with convection initiation most likely across southwest Oklahoma into western north Texas.

These storms will likely merge into a line moving east-northeast through the evening and overnight with the primary hazards being damaging winds gusts and perhaps embedded, QLCS tornadoes. While the overall synoptic-scale pattern and low-level shear/kinetic profiles are favorable for QLCS tornadoes (e.g., ~40 knot flow at 925 mb along the I-35 corridor), there remains uncertainty on whether the low-level thermodynamics will be favorable. However, with dew points in the low 70s deg F from continued moisture advection and low LCLs, there is at least some tornado risk.

There will likely be at least two rounds of showers and thunderstorms through Thursday morning. Locations southeast of I-44 have the best chance at receiving 3 to 4 inches of rainfall with locally higher amounts up to 6 inches possible. A Flood Watch is in effect for this area. The dry slot will impact how much rainfall is expected near and northwest of I-44, so there will likely be a tight gradient of rainfall with amounts quickly decreasing quickly with northwest extent. Rainfall totals along the I-44 corridor will depend heavily on the strength of the dry slot: a stronger dry slot will result in lower amounts, whereas a weaker dry slot will allow for higher totals. Consequently, the probabilistic rainfall forecast has a relatively large range of outcomes with anywhere between ~1" to 5" of rainfall possible along the I-44 corridor (including the OKC Metro, Lawton, Wichita Falls, and Stillwater). The lower and upper range come from the 10th percentile and the 90th percentile of the probabilistic forecast. One way to interpret the 90th percentile is the reasonable worst case scenario or "how bad could it be?" if everything is in alignment. Record-breaking precipitable water values are forecast between 2 to 2.25", so the environment is definitely capable of producing flooding rainfall with a tropical air mass in place.

Rain will likely continue across southeast Oklahoma through the day Thursday with a continued risk for some flooding. Wrap-around showers and low clouds will be possible across the northern half to two-thirds of Oklahoma in close proximity to the upper-level low. That should result in cooler, more seasonable temperatures in the 70s and low 80s deg F. Across southwest Oklahoma into western north Texas, warmer weather is expected in the dryslot region with temperatures in the mid 80s to upper 80s deg F.

Mahale

LONG TERM

(Friday through Monday) Issued at 158 AM CDT Tue Sep 29 2026

The story of the long-term forecast is one of a long-awaited pattern change. Cooler temperatures are expected. Much drier weather will occur in northern/western Oklahoma, while rain chances will linger in southeast Oklahoma and parts of western north Texas.

As the trough responsible for this week's system approaches the polar jet, it will degenerate into an open wave. However, the remnant weakness in the subtropical ridge (still kicking to our west and east) will allow our weather to behave more like early October should. The robust cold front on Thursday will keep sweeping through on Friday, and a reinforcing front is expected early next week as a 1026 mb high dominates the central US. This will keep temperatures at or below seasonal normals as late as next Monday before lee troughing potentially returns.

Showers do linger in the forecast, particularly Friday and Saturday in southeast/central Oklahoma where remnant moisture may be stronger. The reinforcing front will do the job to dry us all the way out: our forecast calls for no mentionable rain chances next Monday.

Meister

AVIATION

(18Z TAFS) Issued at 1223 PM CDT Tue Sep 29 2026

Widespread rainfall through the period may lower ceilings and visibilities through the taf period. Widespread ceiling reduction is expected by tomorrow morning. Additional thunderstorms are possible tomorrow morning, especially across the western third of the area.

PRELIMINARY POINT TEMPS/POPS

Oklahoma City OK 74 87 70 81 / 10 70 100 70 Hobart OK 72 85 68 85 / 20 80 70 30 Wichita Falls TX 74 91 69 85 / 0 80 100 60 Gage OK 66 83 62 80 / 90 90 40 40 Ponca City OK 69 82 67 77 / 20 70 100 90 Durant OK 73 94 71 83 / 0 20 70 100

OUN WATCHES/WARNINGS/ADVISORIES

OK...Flood Watch from Wednesday afternoon through Thursday afternoon for OKZ031-032-040>043-045>048-050>052.

TX...Flood Watch from Wednesday afternoon through Thursday afternoon for TXZ086-088>090.