686
FXUS63 KOAX 120432
AFDOAX

Area Forecast Discussion
National Weather Service Omaha/Valley NE
1132 PM CDT Thu Jul 11 2024

.KEY MESSAGES...

- Dangerous heat is expected for much of the area this weekend
  into Monday, with heat index readings of 100 to 110 degrees
  likely. Sunday and Monday will be the hottest days.

- Could see a few spotty showers and storms tonight and Friday
  night (10-20% chance, highest in northeast Nebraska).

- More widespread storm chances (20-40%) arrive Monday night
  and linger through Wednesday.

&&

.DISCUSSION...
Issued at 330 PM CDT Thu Jul 11 2024

Hourly temperatures have continued to outpace the diurnal trend
originally forecast, so have bumped up this afternoon`s high
temps a bit. The heat is just getting started with a toasty
weekend forecast. Tomorrow will be hotter than today. The day
after that will set the high water mark for the week until
Sunday when upper 90s to triplet digits are forecast for
Sunday. (I`m trying to say that each day will be warmer than the
previous one.)

Have maintained isolated POPs in far far southeast Nebraska and
along the SD state line overnight as moisture transport ramps up
and the summer diurnal jet picks up the pace. But with dry low
levels (5000 ft inverted V sounding), it may be a safer bet to
get a little breezy vs getting a little wet under any
convection. The vast majority of the area will remain dry
through the weekend. QPF is only a few hundredths at best.

Friday will be mostly sunny to partly cloudy with highs close to
90 for most. Heat indices will peak between 90 and 100, shy of
the 105 criteria. WFOs west and north of here, however, have
lower criteria and may need heat headlines for Friday. We may
join the VTEC party on Saturday and Sunday with some sort of
heat headline, at least in the two large metros.

As the upper ridge continues to nose east, temps will climb and
the NWS/CDC heatrisk category will climb into category 3 of 4 -
MAJOR. This represents dangerous heat for most people that do
not have adequate hydration or cooling available.

Saturday remains on track to warrant a heat advisory with max
heat indices over 105 for parts of southeast Nebraska and
southwest Iowa. It will be muggy, too, with corn
evapotranspiration shifting into overdrive. Dewpoints will
easily manage 70s in our Iowa counties. Lows and min apparent
temps slip only into the 70s Friday night through Monday night
in some spots, especially urban areas. This leaves homes with
no A/C difficult to adequately cool. Sunday will be the hottest
day of the week for the northern 2/3 of the CWA. Monday might
beat it out for areas south of I-80 (and - importantly - the
cold front).

The "cold" front lazily slips south on Monday before stalling
out in the vicinity for Tuesday and Wednesday. This will leave
Monday`s highs about ten degrees cooler north of the front than
those of the southern two tiers of counties in the CWA where the
cooler air won`t have yet arrived.

Monday night and Tuesday may bring 20-30% thunderstorm chances
along that front draped west to east across the area. Instead of
diurnal heat driving the thunderstorms, it looks to be a
overnight/LLJ driven event with POPs peaking between midnight
and 6am both nights.

In the cool sector, behind the front, highs on Wednesday and
Thursday will be relegated to near 80F. Don`t expect the
seasonally cool temps to linger, CPC`s 8-14 day and 3-4 week
outlooks suggests odds lean slightly toward warmer than normal
temps for the remainder of the month of July.

&&

.AVIATION /00Z TAFS THROUGH 00Z SATURDAY/...
Issued at 549 PM CDT Thu Jul 11 2024

There is a very low chance (10 to 15 percent) of rain showers
developing across northeast Nebraska (KOFK) between 09 and 12
UTC. Otherwise, VFR conditions are expected to prevail at all
TAF sites for the duration of the forecast period.

&&

.OAX WATCHES/WARNINGS/ADVISORIES...
NE...None.
IA...None.

&&

$$

DISCUSSION...Nicolaisen
AVIATION...Darrah