405
FXUS63 KGID 300002
AFDGID

Area Forecast Discussion
National Weather Service Hastings NE
702 PM CDT Wed May 29 2024

.KEY MESSAGES...

- Thunderstorms will move into the area during the late evening-overnight
  hours with gusty winds and small hail possible.

- Strong to marginally severe thunderstorms possible on Thursday
  the main concerns for large hail and damaging wind gusts.

- Precipitation chances (50-70%) throughout the day on Thursday
  and decreasing throughout the day on Friday (20-50%).

- Scattered precipitation chances this weekend (20-60%) and
  into next week, mainly during the late afternoon-overnight
  hours.

&&

.DISCUSSION...
Issued at 400 PM CDT Wed May 29 2024

This Evening and Overnight...

A line of thunderstorms over the western High Plains will move east
into the area late this evening-overnight, with precipitation
chances for most areas arriving after midnight. Weak instability and
shear will help to keep storms marginally severe at most as they
enter the forecast area. Areas west of Hwy 283 are in the SPC day 1
risk for severe thunderstorms, with wind gusts to 60 mph and small
hail possible. Storms are expected to weaken as they continue to
move east across the area overnight. There is some uncertainty in
how widespread this line of storms will be, with 12z HREF
ensemble members in agreement that the line will become split
as it propagates east.

Thursday and Friday...

Scattered showers and thunderstorms will be ongoing to start the day
on Thursday. How widespread cloud coverage is from these storms will
impact precipitation chances for the rest of the day. Areas that see
sustained clearing will likely be able to destabilize
sufficiently to break the "cap" and have scattered afternoon
thunderstorms. Western portions of the area appear to have the
best chances to see clearing, as the 12z HREF members indicate
showers/storms may continue across eastern portions of the area
late Thursday morning. A cold front will enter northwestern
portions of the area Thursday afternoon which will provide an
additional source of lift for thunderstorm development. Shear
values of 25-30Kts combined with instability of 1000-2000 J/Kg
will allow for a few strong to marginally severe thunderstorms
to develop. The main severe weather concerns would be for large
hail and damaging wind gusts. Severe weather concerns will
decrease overnight as stability increases. Scattered showers and
thunderstorms will continue overnight (25-70%). ECMWF and GFS
ensembles indicate PWAT values will be around 150% of normal
which could lead to locally heavy rainfall of 2-3 inches. Areas
that receive multiple rounds of storms will have the highest
chances to see localized flooding.

Scattered to isolated showers and thunderstorms will come to an end
during the day on Friday. Thunderstorms over the western high plains
may impact western portions of the area late Friday evening, though
there is uncertainty on how far east these storms make it. Highs on
Friday will be in the 70s.


This Weekend...

A series of shortwave troughs will move through the area this
weekend. While the GFS and ECMWF still differ some on the strength
and timing of the troughs, it appears that thunderstorms are
possible (30-60%) during the late afternoon-overnight hours
each day. Moderate instability will be in place on Saturday,
with storms developing off the lee of the Rockies. Storms that
enter the area would have the potential to be severe. Highs on
Saturday will be in the upper 70s to low 80s. Instability will
be higher on Sunday as temperatures climb into the mid to upper
80s, along with higher dewpoints. Warmer air aloft on Sunday may
inhibit thunderstorm development, however a cold front moving
through the area may provide enough forcing for thunderstorms to
develop. Thunderstorms that develop on Sunday would have the
potential to be severe. Details on the timing, evolution and
type of any severe weather chances this weekend will become
clearer as the event gets closer.

Next Week...

Precipitation chances (15-45%) linger into next week, with the
highest chances occurring during the late afternoon-overnight
hours each day. A more impactful shortwave will move through on
Tuesday, though there is still model disagreements on the timing
and strength of this trough. Behind this shortwave a ridge will
begin to build over the western United states. ECMWF and GFS
ensembles disagree on the strength and placement of this ridge,
however warmer and drier weather would move in towards the
middle-end of next week.

&&

.AVIATION /00Z TAFS THROUGH 00Z FRIDAY/...
Issued at 656 PM CDT Wed May 29 2024

KGRI/KEAR TAFS
The wind will stay rather consistently breezy out of the
south southeast overnight into tomorrow. There could be some
low level wind shear tonight, but with the surface winds not
expected to drop off too much overnight it was not strong
enough shear to mention in the TAF. Scattered showers and
thunderstorms could move in anytime after 1 or 2 AM and then
will be around the area at times through the day on Thursday.
Certainly not a rainout, but hard to pinpoint when the showers
and thunderstorms could pass through at this point and thus will
just carry vicinity thunderstorms. Cloud bases should lower
overnight into Thursday morning with MVFR ceilings the most
likely category through much of Thursday morning.

&&

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

&&

$$

DISCUSSION...Davis
AVIATION...Davis/Wesely