Avoca, Nebraska Weather Forecast Discussion

253
FXUS63 KOAX 060308
AFDOAX
Area Forecast Discussion
National Weather Service Omaha/Valley NE
1008 PM CDT Fri Sep 5 2025
.KEY MESSAGES...
- Cool and dry conditions will persist through the weekend, with
  highs in the 60s and 70s. Overnight lows are expected in the
  40s, with the upper 30s possible in western Iowa.
- A gradual warming trend is expected early next week, with
  highs in the upper 70s to mid 80s.
- Shower and thunderstorm chances return Monday into Tuesday
  (30-60% chance), with additional low-end (around 25%) chances
  continuing through the rest of the week.
&&
.DISCUSSION...
Issued at 102 PM CDT Fri Sep 5 2025
Today through Sunday...
Water vapor imagery this afternoon depicts an upper-level low
centered over Ontario, with a mid-level jet streak pivoting around
its axis and driving strong zonal to northwesterly flow aloft across
the region. This setup is ushering in cooler air, with highs topping
out in the 60s, roughly 15 below climatological norms, under mostly
partly cloudy skies and breezy northwesterly winds gusting at 20-30
mph.
Surface high pressure will build in over the weekend, maintaining
dry conditions while easing the gusty winds. Highs will continue
below average, generally in the upper 60s to mid 70s. The dry air
mass will also bring a noticeable drop in humidity and allow
overnight lows to dip into the 40s, with the upper 30s possible in
western Iowa.
Monday and Beyond...
By early next week, the upper-level low will shift eastward,
allowing a mid- to upper-level ridge to build into the central
Plains and gradually warm temperatures through the week. At the
surface, high pressure will slide off to the east, with a warm front
lifting north through the area.
Highs are generally expected in the upper 70s to mid 80s, much
closer to seasonal norms. The weak ridge in place will allow several
shortwave disturbances to track across the region, bringing periodic
precipitation chances. The first arrives Sunday night into early
Monday (PoPs 15-30%), followed by a more potent disturbance late
Monday into Tuesday (PoPs 30-60%). Severe weather potential appears
low overall, with long-range guidance bringing modest instability
but limited bulk shear. Still, both GEFS and ECMWF ensemble-based
machine learning guidance highlights a 5-10% probability for severe
weather Monday into Tuesday. We will have to see how the details
shake out as it approaches.
Confidence in the timing and placement of additional precipitation
chances remains low in this extended time frame, with periodic 15-
30% PoPs through the work week. Overall, more dry periods are
expected than wet.
&&
.AVIATION /06Z TAFS THROUGH 06Z SUNDAY/...
Issued at 1008 PM CDT Fri Sep 5 2025
A shallow bank of mid-level clouds at FL080 interrupts an otherwise
quiet evening, with wind speeds having died to near zero. The weaker
wind speeds have signaled an increasing chance for very patchy
fog, with short-term models targeting western Iowa with any
visibility reductions, with a 30% chance of them reaching the
KOMA terminal from 09-14z. Otherwise, northwesterly winds at
less than 10 kts should hold through the period until they begin
shifting northeasterly after 00z.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...None.
IA...None.
&&
$$
DISCUSSION...Wood
AVIATION...Petersen

NWS OAX Office Area Forecast Discussion