textproduct: Norman

KEY MESSAGES

Updated at 551 PM CDT Sun Sep 27 2026

- Widespread beneficial rainfall expected beginning Tuesday through the end of next week.

- Temperatures will remain above normal through early next week, before cooling down mid-week.

NEAR TERM

(Today and tonight) Issued at 155 PM CDT Sun Sep 27 2026

A weak surface low will be located near the Red River across southwest Oklahoma into western north Texas today. The surface low will result in a north to south temperature gradient with the development of a weak warm front. The hottest weather will be near and south of the surface low across southern Oklahoma and western north Texas with high temperatures in the mid to upper 90s deg F. Across northern Oklahoma, high temperatures will be mid to upper 80s deg F. These temperatures are around 10 to 15 deg F above- normal for late September.

With relatively high precipitable water values (~1.80 inches) and weak/negligible convective inhibition, isolated showers and thunderstorms are possible across south central into southeast Oklahoma late this afternoon (essentially near and just east of the surface low). Cloud-to-ground lightning and strong wind gusts are the potential hazards with any thunderstorms. The chance for showers and thunderstorms will increase this evening into tonight as isentropic ascent/warm air advection increases east of the surface low across southeast Oklahoma. Similar to last night, this activity may persist through the night.

Mahale

SHORT TERM

(Monday through Tuesday night) Issued at 155 PM CDT Sun Sep 27 2026

The above-normal temperatures will continue on Monday with a shortwave ridge aloft across the Southern Plains. High temperatures will once again range from the mid 80s to the mid 90s deg F. Isolated to scattered thunderstorms are possible once again in the afternoon with diurnal heating, primarily across southeast/south central Oklahoma. This is the area where precipitable water values will remain elevated (>1.70 inches). Potential weather hazards associated with any thunderstorms include cloud-to-ground lightning and strong wind gusts.

By Tuesday, a mid/upper-level trough is forecast to dig across the southwest U.S. The trough is forecast to consolidate with the remnants of Hurricane Polo as the trough begins to close-off into a cutoff low. With the system closing-off and slowing down, the most appreciable synoptic-scale ascent (and highest rain chances) will remain to our west during the day Tuesday. However, by late Tuesday/Tuesday night, rain chances will begin to increase across western Oklahoma into adjacent parts of western north Texas. Increased cloud cover ahead of the approaching system will result in the coolest weather across northwest/west central Oklahoma with forecast highs in the mid 80s deg F. Elsewhere, it will be another hot afternoon (for late September) with high temperatures in the upper 80s to mid 90s deg F.

Mahale

LONG TERM

(Wednesday through Saturday) Issued at 126 AM CDT Sun Sep 27 2026

Models are in descent agreement as we go through the middle and latter part of the week into the weekend with regards to the closed low making a slow eastward progression. Along with already present plume of moisture, the remnants of Hurricane Polo will get pulled into the system as well, increasing the potential for heavy and flooding rainfall across the area as we go through the week.

To go along with the rainfall and associated cloud cover, temperatures will cool by the latter part of the week with highs in the 70s and low/mid 80s from Thursday into the weekend.

AVIATION

(00Z TAFS) Issued at 551 PM CDT Sun Sep 27 2026

Storm activity may initiate during the next 8 hours across southeast Oklahoma which could impact only terminal KDUA. There is a 30% probability of isolated storms for terminal KDUA between 00-08Z. Although ceilings should be high at terminal KDUA but reduced visibilities in rain could degrade that terminal to at least an MVFR category for a short period should a storm pass over.

A stratus deck producing ceilings is expected to develop tonight although expecting ceilings to be high enough (4,000 ft) across 4 of our terminals in central through northcentral Oklahoma (KOKC, KOUN, KSWO & KPNC) keeping those terminals in a VFR category. However our remaining terminals could reduce to an MVFR or IFR category between 12-18Z then returning to a VFR category after 18Z. Dense fog is possible tonight across the Texas & Oklahoma Panhandles which may also impact terminal KWWR in northwest Oklahoma between 13-16Z also keeping that terminal in an IFR category. There is a 20% chance of storm activity returning to southeast Oklahoma after 18Z but that probability is too low at this time to be in the terminal forecast for KDUA but mentionable in this discussion. Surface winds generally out of the northeast at 5-10 kts but expected to veer in direction more easterly by 12Z at some of our terminals and likely stay that way after 18Z.

PRELIMINARY POINT TEMPS/POPS

Oklahoma City OK 69 90 71 91 / 10 10 0 10 Hobart OK 68 92 72 91 / 0 0 0 10 Wichita Falls TX 69 95 72 96 / 10 10 0 0 Gage OK 63 87 67 84 / 0 0 0 50 Ponca City OK 65 84 67 87 / 10 10 0 30 Durant OK 67 92 69 95 / 40 30 10 0

OUN WATCHES/WARNINGS/ADVISORIES

OK...None. TX...None.