447
FXUS63 KOAX 122247
AFDOAX

Area Forecast Discussion
National Weather Service Omaha/Valley NE
547 PM CDT Fri Jul 12 2024

.KEY MESSAGES...

- Spotty showers are possible tonight south of I-80.

- 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.

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

&&

.DISCUSSION...
Issued at 333 PM CDT Fri Jul 12 2024

Dry conditions across the area today align with the removal of
the marginal convective outlook for the day. CAMs, inconsistent
from run to run this morning, are drying out as well. Believe
the EML`s capping should hold through the afternoon. Have
reduced POPs to sub-25% for the next 24 hours with best chances
overnight near the Kansas/Nebraska state line.

The upper level ridge that has been garnering headlines and
setting record temperatures on the other side of the Rockies for
the past few days will continue to nose into the central
plains as the eastern CONUS trof begins to break down. Heights
and max temps climb through the weekend with some locations
(north) forecast to peak on Sunday afternoon and some (south)
waiting for Monday afternoon to hit the week`s zenith.

Despite being on the 7th page of the calendar, temperatures at
850 hPa and 700 hPa will be near the 100th percentile this
weekend as will the specific humidity at 925 hPa. Have
continued to push dewpoints higher than most guidance due to the
climatological peak of the Corn Belt`s evapotranspiration.
Dewpoints this afternoon are already outperforming the forecast,
so Saturday and Sunday`s numbers may need to be boosted even
further. Widespread dewpoints in the 70s are forecast each
afternoon adding notable mugginess to the high heat.

Didn`t have to spend much time collaborating on heat headlines
with neighboring offices due to this CWA being ringed by heat
advisories for Saturday. From 1pm to 8pm, apparent temps will
run as high as 109F. Did not extend the advisory overnight as
minimum apparent temps fall below the 75 degree criteria. This
will help housing units with no A/C to cool off at least
partially and temporarily. Have maintained the excessive heat
watch for Sunday and Monday when some locations will be even
hotter. Consecutive days of heat have been shown to increase
heat related injuries and illnesses. Especially concerning will
be the Lincoln and Omaha/CB metros as urban areas tend to better
hold the heat through the night and vulnerable populations tend
to be clustered.

Monday will bring partial relief in the form of a cold front...
at least to the northern half of the area. The extreme heat is
forecast to hold on for one more day in areas south of I-80
where the front falls short. Max temps will peak in the lower to
mid-90s north of the Platte River with triple digits possible
south of it.

The front continues to sag south on Tuesday and Wednesday. The
front will help produce occasional chances for showers with POPs
peaking at 30% or so for late Monday night (nocturnal jet) and
even better chances forecast for Tuesday night. Increased cloud
cover, scattered showers, and continued weak CAA. Highs on
Wednesday and Thursday are consigned to the low 80s.

&&

.AVIATION /00Z TAFS THROUGH 00Z SUNDAY/...
Issued at 547 PM CDT Fri Jul 12 2024

VFR conditions are expected to prevail through the forecast
period. Southeasterly winds are expected to calm under 12 kts
by 00Z and gradually shift to southerly overnight. A few high
clouds at FL250 will move through overnight.

&&

.OAX WATCHES/WARNINGS/ADVISORIES...
NE...Heat Advisory from 1 PM to 8 PM CDT Saturday for NEZ011-012-
     015>018-030>034-042>045-050>053-065>068-078-088>093.
     Excessive Heat Watch from Sunday afternoon through Monday
     evening for NEZ034-042>045-050>053-065>068.
IA...Heat Advisory from 1 PM to 8 PM CDT Saturday for IAZ043-055-
     056-069-079-080-090-091.
     Excessive Heat Watch from Sunday afternoon through Monday
     evening for IAZ055-056-069-079-080-090-091.

&&

$$

DISCUSSION...Nicolaisen
AVIATION...Wood