791
FXUS63 KGID 282219 CCA
AFDGID

Area Forecast Discussion...CORRECTED
National Weather Service Hastings NE
519 PM CDT Mon Sep 28 2026

.KEY MESSAGES...

- Heavy rainfall upwards of 4 cumulative inches is expected
  fromTuesday afternoon through Thursday evening. Flooding will
  be possible, and thus a Flood Watch has been issued for all
  counties across the CWA.

- Likeliest rainfall totals from Tuesday through the end of the
  dayon Thursday will be in the 2.75 - 4 inch window. A worst-
  case scenario can bring 5+ inches.

- Thursday is expected to be breezier with gusts of 25 - 30 mph.

&&

.DISCUSSION...
Issued at 343 PM CDT Mon Sep 28 2026


Rest of Monday and Tonight...

A few isolated showers and thunderstorms (primarily near and
north of the KS / NE state line) cannot be ruled out this
afternoon into evening, however a substantial cap casts a good
deal of doubt on these storms successfully initiating.
Regardless, if storms develop, no severe weather is expected.

As for tonight, a glancing blow of showers and a few
thunderstorms is expected for our far northwestern CWA as a
joint mid-level and low-level jet impinge on the area through
Wednesday morning. No flooding is expected from these showers.

Tuesday...

The main show of the week arrives on Tuesday. Our initial jet
streak will gradually pull off to the northeast through Tuesday
morning, but a secondary pulse will arrive round noon. Vorticity
advection is not expected to ever fully die down, and thus
broken rounds of showers and storms are expected through the
day. The likeliest times for precip will be from noon onwards,
with the likeliest time for a break in the mid-morning between
jet streaks.

Tuesday night (particularly 1 AM - 4 AM Wednesday morning) is
expected to strongly uptick the intensity of precip (and thus
flooding risk). At this time, the remnants of Hurricane Polo
will advance into our area after getting sucked into our main
trough. Vorticity advection, a favorable mid-level jet with
strong diffluence, a 35+ kt low-level jet, and warm air
advection all look to arrive with saturated profiles through the
depth of the troposphere. By sunrise on Wednesday morning, mean
24-hr precip of 0.5 - 1.5 inches (with the heaviest favored
south of I-80) is expected. As a potential worst-case scenario,
12z HREF 95th- percentile 24-hr totals by sunup on Wednesday
exceed 3.5 inches with the heaviest yet to come on WED. Given
antecedent wet soils, flooding will be a concern. WPC currently
holds us in a Level 2 out of 4 Slight Risk for flash flood
exceedance for TUE.

Wednesday...

Wednesday is highly likely to be a washout with rain and storms
carrying us through the day. Our trough, jets, and saturated
profiles with PWATs >150% of normal for this time of year will
continue to provide for additional flooding risk. WPC maintains
us us in a Level 2 out of 4 Slight Risk for flash flood
exceedance on WED. 13z NBM guidance suggests new Wednesday and
Wednesday night rainfall totals of 1.5 - 3 inches, with 95th-
percentile wosrt-case totals locally exceeding 5 inches in our
central CWA. Of note for our southern CWA, where forcing remains
more optimal, a few strong to severe thunderstorms will be
possible, with SPC currently outlining these counties in a Level 1
out of 5 Marginal Risk for severe thunderstorms.

Exactly where the heaviest rain falls will depend on how far
northward the nose of the jets can reach, and the northern edge
of the jet will likely produce a sharp cutoff in rainfall
totals. THE EPS and GEFS tend to favor our central CWA as the
northern edge, while the 12z REFS favors our northern counties.
In addition, some breaks in rainfall are expected, but dry time
will be the exception and not the rule.


Thursday...

Precip looks to linger on Thursday, primarily for our KS
counties. By evening, precip is expected to finally die off as
our favorable forcing ejects to the east. Despite the heavy
rainfall coming to an end, the trough core itself will likely
linger on Thursday, bringing cooler temperature in the low 60s F
with overnight lows into FRI able to dip into the mid 40s.
Additionally, breezier conditions with wind gusts of 25 - 30 mph
are expected.

In all, by sundown on Thursday when rain is expected to end,
likeliest cumulative totals across the CWA look to be 2.5 - 4
inches, with a worst-case scenario of 5+ inches per 13z NBM
guidance.

Friday into Weekend...

Friday, Saturday, and Sunday are expected to stay dry with
relatively cooler temperatures prevailing. The 06s GEFS suggests
that the next shortwave trough will move in from Canada on
Saturday, but right now precipitation associated with this
trough looks unlikely.


&&

.AVIATION /18Z TAFS THROUGH 18Z TUESDAY/...
Issued at 1252 PM CDT Mon Sep 28 2026

For KGRI/KEAR Airports:

Primary aviation impacts will be ceilings and visibility
throughout the next 24 hours. IFR ceilings are holding on at
KGRI and just on the MVFR threshold at 18z at KEAR. Have been
fairly pessimistic about ceilings at KGRI over the next 24
hours. Do have a period of VFR ceilings at KEAR/KGRI evening
into early overnight before dropping again early Tuesday in
advance of the next round of rain. While some scattered showers
may be present early (before 12z Tuesday), feel the better
chance for more widespread rain will be mid-morning. While a
rumble of thunder cannot be ruled out, but primarily it`ll be
rain showers.

&&

.GID WATCHES/WARNINGS/ADVISORIES...
NE...Flood Watch from Tuesday evening through Thursday evening for
     NEZ039>041-046>049-060>064-072>077-082>087.
KS...Flood Watch from Tuesday evening through Thursday evening for
     KSZ005>007-017>019.

&&

$$

DISCUSSION...Began
AVIATION...Billings Wright