101
FXUS64 KOUN 201821
AFDOUN

Area Forecast Discussion
National Weather Service Norman OK
121 PM CDT Fri Sep 20 2024

...New UPDATE, AVIATION...

.UPDATE...
Issued at 117 PM CDT Fri Sep 20 2024

POPS for late this afternoon were increased slightly for many
areas north of I-40. With continual moisture advection into
central Oklahoma and decreasing clouds and the approach of the
mid-level wave from NM, chances are greater than near zero. Still,
storms in this region are expected to be isolated with possibly a
few more closer to Kansas.

&&

.KEY MESSAGES...
Updated at 117 PM CDT Fri Sep 20 2024

- Hot/humid conditions continue through Saturday, followed by cooler
weather starting Sunday.

- A few isolated storms possible over northern Oklahoma this
  afternoon, with the potential for a severe downburst or two.

- Medium chances for showers and storms Saturday night through
  Monday morning associated with a cold front.

&&

.SHORT TERM...
(Today and tonight)
Issued at 204 AM CDT Fri Sep 20 2024

Friday will be another hot day, featuring near record high
temperatures (upper 90s / lower 100s). With humidity, heat indices
will range from about 102 to 107 degrees. HREF guidance suggests
most of our eastern counties will have a 40-70% chance of hitting
heat advisory criteria. Winds will remain light.

An upper high centered over central Texas will keep most of the area
mostly sunny. A few isolated storms may form in parts of northern
Oklahoma this afternoon, along the northern periphery of the upper
high. Environment is not too impressive in regard to organized
convection, but could support a strong downburst or two.

Friday night will continue the warm and humid theme with lows in the
70s and dewpoints in the 60s.

Day

&&

.LONG TERM...
(Saturday through Thursday)
Issued at 204 AM CDT Fri Sep 20 2024

The week will end with one more hot day (though slightly less hot
than Friday).

An upper low swinging up through the four corners region through
Colorado will support increasing chances for showers and storms in
northwest Oklahoma Saturday night. As this low continues to lift,
rain chances will spread across the area Sunday and Sunday night. A
cold front will sweep through the forecast area on Sunday, providing
some focus for this convection and bringing cooler temperatures
behind it. Overall, the synoptic setup looks supportive of a few
strong to severe thunderstorms during the afternoon/evening with
modest instability and deep layer shear predicted. High PWATs will
mean we will need to watch for a heavy rain and flooding potential
as well.

Sunday looks to feature a tight temperature gradient with
cooler temperatures generally in the 80s northwest of I-44 and some
lingering 90s southeast of that boundary. By Monday, the entire
forecast area will have dropped into the 70s and low 80s. These
cooler temperatures should continue through much of next week.

Another system is supposed to swing through the central plains on
Tuesday, though there is considerably more uncertainty with that
one. Models differ as to whether to cut off the low before it
traverses Oklahoma. For now, we`ll continue with 20-40% PoPs on
Tuesday / Tuesday night associated with this system.

Day

&&

.AVIATION...
(18Z TAFS)
Issued at 117 PM CDT Fri Sep 20 2024

VFR conditions are expected through the period outside of isolated
thunderstorms in northern Oklahoma late this afternoon and early
evening. Winds will be southerly with occasional gusts.

&&

.PRELIMINARY POINT TEMPS/POPS...
Oklahoma City OK  74  96  73  88 /   0   0  10  40
Hobart OK         72  97  71  86 /   0   0  20  50
Wichita Falls TX  73  98  74  93 /   0   0   0  30
Gage OK           71  95  61  74 /  20  30  60  50
Ponca City OK     76  98  71  86 /  20  10  40  60
Durant OK         74  98  73  94 /   0   0   0  10

&&

.OUN WATCHES/WARNINGS/ADVISORIES...
OK...Heat Advisory until 8 PM CDT this evening for OKZ007-008-012-013-
     018>020-024>032-038>048-050>052.

TX...Heat Advisory until 8 PM CDT this evening for TXZ090.

&&

$$

SHORT TERM...14
LONG TERM....14
AVIATION...09