textproduct: Norman

KEY MESSAGES

Updated at 229 AM CDT Fri Sep 18 2026

- Heat wave and elevated fire danger persists through at least Saturday.

- A cold front arrives this weekend, bringing medium-high rain chances and less hot temperatures next week.

NEAR TERM

(Through Friday) Issued at 229 AM CDT Fri Sep 18 2026

Another hot day is expected today with high temperatures similar or slightly lower than yesterday. Although the upper ridge remains camped over the southern Plains, the magnitude of the high is decreasing with the 500 mb high progged to be closer to 596 dm than yesterday's 599 dm observed here at KOUN as well as SGF, LZK, SHV, and FWD. Forecast heat indices are slightly lower than yesterday. HI values may push close to 105 again in Atoka and Bryan Counties, but are in general below Heat Advisory criteria and currently do not plan on issuing an advisory.

Fire weather concerns continue to mainly be driven by very dry fuels driven by the ongoing drought. Minimum humidity is expected to remain above 25 percent and sustained wind speeds generally below 20 mph, neither meeting traditional Red Flag criteria. However we have continued to see wildfires this week in the dry fuels without the weather meeting traditional criteria. Will issue a Fire Danger Statement covering much of the southern half of the forecast area where ERC (Energy Release Component) calculations are this highest.

SHORT TERM

(Friday night through Sunday night) Issued at 229 AM CDT Fri Sep 18 2026

The magnitude of the upper ridge will continue to decrease this weekend, and increased upper-level flow will develop across northwest Oklahoma as least as the ridge weakens and shifts southeast and an upper trough moves east toward the southern Rockies. An initial shortwave in the southwesterly flow aloft Saturday morning moves into the central Plains, and behind it a cold front slides south through Kansas and looks to enter the Sooner State early Saturday evening. Rain chances increase Saturday afternoon in the northwest, with wider chances Saturday night into Sunday with the front in the area and southwesterly flow aloft. Instability will support thunderstorms with some potentially strong storms as well as SPC's marginal risk of severe storms, but at this point we do not expect widespread severe. It will be quite warm again Saturday ahead of the front with cooler temperatures spreading into the area on Sunday as the front continues to move south, although the movement of the front will be slow through Sunday until the weakening trough moves over the area late Sunday, then the front will push south more quickly Sunday night.

Humidity and wind will again not meet traditional fire weather criteria on Saturday, but the fuels will remain receptive. The axis of lowest humidity (near 25 percent) may even shift more toward southeastern Oklahoma on Saturday. By Sunday, minimum humidity values look to be higher (30-50 percent).

LONG TERM

(Monday through Thursday) Issued at 229 AM CDT Fri Sep 18 2026

By Monday morning, the cold front will have moved through much of the area bringing a more seasonable airmass, although southern areas may still be quite warm Monday depending on the specific timing of the front. And the weather through the week will be dominated by the post-frontal surface ridge across the Midwest into the Plains. Precipitation chances Monday will primary be closest to the cold front in the south. Later in the week the highest precipitation chances will primarily be across the west with post-frontal upslope surface winds helping to produce convection over the High Plains with the storms moving toward western portions of the forecast area. Temperatures will remain closer to seasonable averages than we have seen in quite a while.

AVIATION

(06Z TAFS) Issued at 1030 PM CDT Thu Sep 17 2026

VFR conditions will continue under mostly clear skies and a light southerly wind overnight. Patchy diurnal cumulus and an occasionally gusty south-southwesterly wind are likely during the day on Friday.

Safe travels!

Ungar

PRELIMINARY POINT TEMPS/POPS

Oklahoma City OK 98 75 98 75 / 0 0 0 10 Hobart OK 99 75 100 75 / 0 0 0 20 Wichita Falls TX 101 74 101 74 / 0 0 0 0 Gage OK 98 74 99 71 / 0 0 30 30 Ponca City OK 96 74 97 72 / 0 0 0 40 Durant OK 101 73 100 73 / 0 0 0 0

OUN WATCHES/WARNINGS/ADVISORIES

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