Forecast Discussion
NWS Omaha/Valley, NE

824
FXUS63 KOAX 311045
AFDOAX

Area Forecast Discussion
National Weather Service Omaha/Valley NE
545 AM CDT Mon Mar 31 2025

.KEY MESSAGES...

- Today will be pleasant with light winds as high temperatures
  reach the 40s to 50s under partly cloudy skies.

- Next storm system arrives Tuesday (30-60% PoP chances) and continues
  into Wednesday (widespread 60-90% PoP chances). A slight risk
  of severe weather (15% chance) across south central into
  eastern Nebraska and western Iowa.

- Benign weather returns for Thursday with next round of rain
  possible Thursday night into the weekend (15-30% chance).

&&

.DISCUSSION...
Issued at 400 AM CDT Mon Mar 31 2025

Clouds remain socked in across most of our area early this
morning as High Pressure out of Canada sags south into the
Central Plains. We`ll see these clouds slowly break up and clear
through the day today. Light northerly winds will be keeping
temperatures seasonably cool with highs in the low-to-mid 50s
this afternoon.

The upper-level pattern shows a strong Polar Jet Streak across
the eastern Pacific pushing into northern California this
morning. We`ll see this jet streak push inland and sag south as
the trough off the coast of the PacNW pushes inland pivoting the
upper-level flow over the Central Plains to southwesterly by
Tuesday morning. The developing area of low pressure on the lee
side of the Rockies brings an elevated warm front through
eastern Nebraska and western Iowa late Monday night with
increasing southerly 850-mb winds across the area. We`ll see
these strengthening southerly winds mix down to the surface
mid-morning on Tuesday with winds 20 to 30 mph and gust
approaching 40 mph by Tuesday afternoon.

As the elevated warm front moves through we`ll see rain chances
return, starting in northeast Nebraska Monday night (40-70%
chance) spreading south Tuesday morning (20-40% chance). The
amount of rain across southeast Nebraska during the day on
Tuesday will be highly dependent on the track of the surface low
which has been trending farther north over the last few runs. If
the surface warm front pushes north into southeast Nebraska, we
could see an increased potential for severe storms Tuesday
evening.

During the evening hours we`ll see the surface low push into
south central Nebraska as it lifts to the northeast. This will
trigger the potential for strong storms starting around 7PM.
While initially isolated to widely scattered, there will be
enough environmental shear for the potential for low-topped
supercells to develop in a only moderately unstable environment
(800-1100 J/kg MUCAPE is the average). These storms will
eventually merge into a line which will move across the rest of
eastern Nebraska into western Iowa through the night.

As of the latest models, the primary hazard looks to be large
hail as models show instability being cut-off from the surface
by a warm nose around 925 mb. This will mean storms will be
fairly high-based which reduces the potential for tornadoes and
significant damaging winds. We still could see strong winds out
of these storms up to 60 mph, however.

The general consensus is that the better environment for very
large hail will be south across Kansas and Missouri, though
there is an aforementioned scenario in a few of the ensemble
members where we see the steeper lapse rates creep north into
eastern Nebraska and southwest Iowa. The Storm Prediction Center
is hedging farther north on their significant hail threat due
to the tendency for these systems to overperform.

As we go into Wednesday we`ll see showers lingering through the
morning lifting north out of our area during the afternoon.
Westerly winds on the back side of the surface low will continue
to be fairly strong until the pressure gradient starts to relax
as the surface low gets farther away Wednesday night. Wednesday
night we`ll also see the trailing cold front from the surface
low sag south across our area and become stationary.

The stationary front remains across our area through Thursday
with only a modest presence at the surface. Temperatures
Thursday afternoon will peak in the 50s across our area under
partly sunny skies.

Going into the end of the week, we continue to see a strong
southwesterly flow regime in place across the Central Plains
with a deep upper-level trough over the Southwestern US and a
ridge along the East Coast. Thursday night into the weekend
we`ll likely see subtle shortwaves eject off the surface trough
across our area bringing chances for showers on Friday. Going
into the weekend, model consensus starts to break down with
significant differences in how the trough interacts with a
strong ridge building into southwestern Canada. The NBM keeps
low chances for precipitation through the weekend and fairly
stable temperature trends which seems fair given the
uncertainty.

&&

.AVIATION /12Z TAFS THROUGH 12Z TUESDAY/...
Issued at 542 AM CDT Mon Mar 31 2025

Lingering MVFR ceilings are hanging around a few sites this
morning. Ceilings are expected to break up and improve, fully
returning to VFR conditions by 12-13Z. Winds will remain light
and variable today. Towards the end of the forecast period
(07-09Z), southeasterly winds will increase above 12 kts along
with rain shower chances (10-40%) and overcast skies at FL100
moving into the area.

&&

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

&&

$$

DISCUSSION...McCoy
AVIATION...Wood

NWS OAX Office Area Forecast Discussion

Forecast Discussion
NWS Hastings, NE

942
FXUS63 KGID 311204
AFDGID

Area Forecast Discussion
National Weather Service Hastings NE
704 AM CDT Mon Mar 31 2025

...Aviation Update...

.KEY MESSAGES...

- The vast majority of weather concerns over the next week are
  focused on Tuesday (strong winds, at least a modest severe
  storm threat, and at least near-critical fire weather
  conditions).

- While Tuesday is the main day of concern, an overall-active
  weather pattern with various/intermittent rain chances will
  persist through at least Saturday before a pattern change
  turns the switch toward a quieter/higher-confidence dry
  weather pattern starting around Sunday and perhaps several
  days thereafter.

- While SPC has maintained (actually expanded) a Slight Risk
  (level 2 of 5) threat for severe storms Tues afternoon-evening
  to the vast majority of our forecast area (CWA), here at the
  local level we are still seeing a fair amount of uncertainty
  regarding not only the magnitude of the potential threat, but
  also how much of our area could be under the gun (some models
  suggest the main threat will focus almost entirely east of
  Hwy 281).

- How far west/east the Tuesday severe storm threat extends will
  depend heavily on how fast a dryline advances eastward, as a
  faster/earlier passage of this boundary would actually LOWER
  any severe storm threat in our west-southwest counties, but
  would conversely INCREASE the fire weather threat,

- Temperature-wise: With the exception of warmer readings
  Tuesday (most places well into the 60s/70s, most of the next 7
  days will feature very typical early-spring highs mainly in
  the 50s and lows mainly 20s-low 40s.

&&

.DISCUSSION...
Issued at 554 AM CDT Mon Mar 31 2025

-- PRIMARY 7-DAY FORECAST BIG PICTURE TRENDS,
 CHANGES/UNCERTAINTIES:

- Overall no notable changes from our previous issuance
  yesterday afternoon, as although actual cumulative rain
  AMOUNTS seem to be leaning toward the disappointing side for
  most of our CWA, our forecast is nonetheless littered with
  several (at least small) chances for rain mainly between
  tonight and Saturday thanks to the passage of essentially
  three separate low pressure systems passing through in active
  southwesterly flow aloft.

- See below for more details, but even at this fairly close time
  range the magnitude, areal coverage, etc. of the potential
  severe storm threat Tues afternoon-evening remains fairly
  uncertain (to quote SPC`s Day 2 outlook..."A somewhat
  complicated convective evolution...").

 Compared to 24 hours ago, some of the latest model data points
to our potential threat:
 1) arriving/ending a bit earlier (mainly confined the 3 PM-
Midnight time frame...with Midnight perhaps being plenty
generous)...2) Perhaps largely sparing at least the western 1/3
to 1/2 of our CWA, and instead focusing mainly east (although
this is not yet a "sure thing").

- If the dryline shoves east-northeast into especially our
  southwestern CWA any sooner than currently depicted (and
  especially if it warms more than currently indicated, we could
  be headed toward potentially-critical fire weather issues in
  at least a handful of our counties (at least near-critical
  criteria already appears likely, and this has been added to
  our Hazardous Weather Outlook (HWOGID) this morning.


-- 7-DAY FORECAST CHRONOLOGICAL BREAKDOWN:
- CURRENT/RECENT WEATHER SCENE AS OF 5 AM:
Although some elevated radar returns (indicative of possible
spotty sprinkles/flurries) are starting to brush toward some of
our extreme western counties...see below for more on this), as
expected it`s been a dry/precip-free night so far within our
entire CWA. Aloft, water vapor satellite and short term model
data reveals mainly westerly flow, and although there are some
weak ripples of lift moving through...for the most part we
remain "in between" larger-scale low pressure systems both well
to our east/west. At the surface, an extensive high
pressure/ridge axis has nosed down into our area from Canada/the
Dakotas, with the main difference from 24 hours ago being
resultant lighter north winds (generally only 5-10 MPH most
spots). Sky/cloud cover continues to be a tricky forecast
entity, as while clouds in most of our CWA are not as low as
they were even 6-12 hours ago, cloud cover is currently pretty
solid CWA-wide. As a result, and despite the lighter winds, low
temps appear on track to hold up a little bit warmer than
expected here 24 hours ago, with most places bottoming out no
colder than 30-34 degrees.


- TODAY:
Overall no big concerns to speak of, with the main uncertainties
being sky cover and whether or not some spotty
sprinkles/flurries end up affecting some of our mainly far
western counties yet this morning.

Starting off with precip potential, although weak overall, a
combination of subtle mid-level lift/saturation out ahead of an
upper level jet axis approaching from the west-southwest is
driving some spotty light precip running along a generally
northwest-to-southeast xis over mainly southwest NE/northwest
KS. While it should be very low impact, have included a basic
chance of flurries/sprinkles through much of the morning for
primarily a handful of our far western counties where this
activity is overall most favored. Otherwise, the majority of our
CWA carries a dry forecast today.

As mentioned, cloud cover today is tricky/somewhat uncertain, as
while our current forecast averages out to "partly cloudy" for
the day as a whole, whether clouds actually break up/scatter out
aggressively enough to avoid more so "mostly cloudy" is still
up for debate, as even if lower clouds scatter out, a fair
amount of mid-high level clouds could remain up above. Of higher
confidence are winds, which will remain light (mainly no more
than 5-10 MPH) through at least early-mid afternoon as the
passing ridge axis shifts direction from northerly, to easterly,
to southeasterly. However, by especially late afternoon-early
evening, a steadier south-southeast breeze will kick in, with
especially our western zones seeing gusts of at least 20-25 MPH
before sunset.

Temperature-wise, while cloud cove (or lack thereof) could
easily make a 3-5 degree difference, have made very little
change to previous forecast, calling for most places to top out
somewhere between 51-56.


- THIS EVENING-OVERNIGHT:
As the leading edges of more pronounced upper lift out ahead of
the primary western United States trough enters our region and
induces the development of a stout low level jet, a band of rain
showers is expected to develop at some point mainly after 10 PM
and swing through parts of our CWA from west-southwest to east-
northeast. Consensus of various models suggests that this
activity is most favored in counties north of I-80, and although
we are carrying low-end rain chances as far south as into our KS
zones, much of our southern half could easily stay bone dry
overnight. A rogue rumble or two of (non-severe) thunder cannot
be ruled out, but this chance seemed low enough to omit from
formal forecast mention.

At the surface, the main feature tonight will be strengthening
southeast winds, with sustained speeds commonly 15-25 MPH/gusts
25-30 MPH. The combo of clouds and these winds will keep
temperatures elevated, with lows aimed mainly low 40s and some
places likely steadying out or rising slightly late.


- TUESDAY-TUESDAY NIGHT:
Have already covered the "big picture" points above, but these
24 hours are clearly our main issue this week as a strong upper
level system and associated surface low pass through our region.
Although finer scale details vary, general consensus of models
puts a strong (roughly 990 millibar) surface low over northeast
CO at sunrise Tues, with this low reaching northwest KS by mid-
afternoon and then tracking across our CWA through late
afternoon-evening before departing east and ending up somewhere
near the IA/NE border by sunrise Wednesday.

Of highest confidence is that south-southeasterly winds will be
fairly strong out ahead of the low, with much of our CWA seeing
sustained 30 MPH/gusts 40-45 MPH much of the day. However, one
of the big/lingering question marks is how far north vs. south
the main low tracks as it crosses our CWA, as a trend toward a
more northerly track is now making it look increasingly likely
that a trailing dryline could surge into especially our
southwest zones by mid-late afternoon, increasing the fire
weather threat. Meanwhile, the speeds of this boundary, along
with one of the second biggest question marks (how much low-
level moisture will arrive before storms form?) will very much
determine whether our severe storm threat is perhaps a bit more
widespread and across more of our area...or perhaps more muted
and/or confined mainly to our eastern zones. For what it`s
worth, the latest runs of models such as NAM/RAP are less robust
with instability/CAPE versus 24 hours ago, with both lower-level
and elevated CAPE perhaps struggling to exceed 500-1000 J/kg in
our CWA...mainly due to dewpoints only making it into the mid
40s to perhaps low-50s at best ahead of storm initiation. That
being said, deep layer shear will be VERY strong (at least
50-70KT), so it might not take much instability to produce at
least marginally-severe hail and/or damaging wind gusts (there
is some question though about the significant/large hail threat
currently highlighted by SPC over most of our CWA). Fortunately,
the modest/late-arriving moisture should in theory greatly mute
a tornado threat, and if one were to materialize it would
appear to be later in the evening and at least slightly off to
the east-southeast of our CWA (we agree with SPC leaving our CWA
void of tornado probabilities at this time). No matter how much
(or how little) storms and potential severe weather we see, the
threat will likely be over by Midnight at the latest as
instability departs.

In other departments Tuesday, high temps were nudged up very
slightly, with most of our Nebraska counties aimed mid-upper 50s
with warmer 70s more favored near/south of the state line. That
being said, if the dryline punches in faster then more of our
area could reach 70s and southwest zones could even approach 80
(increasing the fire threat).


- WEDNESDAY-WED NIGHT:
Although we`ll have to watch counties especially along/south of
the state line for at least a near-critical fire weather threat,
this should be a mainly dry but very breezy day as west winds
will be sustained 20-25 MPH/gusts 30-35 MPH out of the west on
the backside of the departing low. Some spotty rain showers
cannot be ruled out, but most areas will surely stay dry. High
temps will vary a bit, ranging from mid-upper 50s in most Neb
zones, to more so low-mid 60s near/south of the state line.


- THURSDAY-FRIDAY:
While instability will be little-to-none, the arrival of another
disturbance in southwesterly flow aloft brings a return of
intermittent rain chances, with "exact" coverage and amounts
plenty uncertain (but not looking very heavy). High temps mainly
low-mid 50s both days.


- SATURDAY-SUNDAY:
Saturday daytime-night, the "last gasp" of our parade of upper
level lows is slated to pass through, with continued chances for
rain and MAYBE some slushy/wet snow especially if the
wetter/more aggressive ECMWF solution comes to fruition (note
the GFS is drier and shunts precip to our south). Either way,
both primary models support a dry Sunday as we start a
significant pattern change to benign north-northwesterly flow
aloft. High temps both days aimed low-mid 50s, but if wetter
ECMWF verifies then Saturday could easily trend cooler.

&&

.AVIATION /12Z TAFS THROUGH 12Z TUESDAY/...
Issued at 704 AM CDT Mon Mar 31 2025

For KGRI/KEAR Airports:
- General overview:
Especially beyond these first few hours, overall-high confidence
in VFR ceiling/visibility prevailing through the period. The
main issues arise this evening-overnight as surface winds
increase from the southeast, a chance of passing rain showers
arises, and moderately-strong low level wind shear develops.

- Ceiling/precipitation details:
Although mainly KEAR could hold onto high-end MVFR ceiling for a
few more hours (covered via TEMPO), both sites should prevail no
worse than low-end VFR today, and with any ceiling mainly near-
to-above 8K ft. AGL this evening-overnight. Although not a high
chance, there is at least some chance of passing rain showers
tonight mainly during the 04-10Z time frame, and a PROB30 group
has been introduced to address this.

- Wind details:
- Surface winds:
As a ridge axis passes through, a mainly light/variable
direction regime will prevail into this afternoon. By mid-late
afternoon and especially this evening, southeast winds will
gradually increase, with gusts of at least 15-20KT in place by
around 00Z, and gusts at least 20-25KT materializing by around
06Z.

- Low level wind shear (LLWS):
Although it will be quite breezy at the surface, a strong low
level jet with speeds to around 45KT will kick in by around 07Z
out of the south-southeast, creating at least 30KT of shear
magnitude between the surface and this level.

&&

.GID WATCHES/WARNINGS/ADVISORIES...
NE...None.
KS...None.

&&

$$

DISCUSSION...Pfannkuch
AVIATION...Pfannkuch

NWS GID Office Area Forecast Discussion