484
FXUS63 KGID 200011
AFDGID

Area Forecast Discussion
National Weather Service Hastings NE
711 PM CDT Sun May 19 2024

.KEY MESSAGES...

- Thunderstorms largely evade south central Nebraska and north
  central Kansas this evening and overnight, though a brief
  flare up isolated strong storms can`t be ruled out late S of
  the state line.

- Another round of storms (some severe) is expected on Monday
  afternoon through Monday night, though details on
  timing/coverage remain somewhat uncertain. The trend has been
  for activity to arrive/develop later (near or after sunset).

- Storm chances linger into Tuesday, with conditions trending
  drier Tuesday evening through Wednesday.

&&

.UPDATE...
Issued at 710 PM CDT Sun May 19 2024

Will be working on an update shortly to lower shower and tstm
chances further for the rest of the evening and overnight as it
appears the bulk of activity will remain mostly W and S of the
forecast area. Hopefully we`ll be able to coordinate a watch
cancellation soon, as well...though the low confidence of what
exactly will happen with the convection in NW KS may dictate
otherwise. Bottom line, though, even if the low end chance for
additional tstms indeed pans out, this would likely be limited
to far SW-S zones, and be marginally severe, at best. This is
due to persistent cloud cover that has done well to reduce
destabilization potential and keep temps considerably cooler
than once forecast. Furthermore, latest model guidance suggests
the bulk of convergence and WAA on nose of developing LLJ will
be "blocked" by the ongoing MCS over central KS. Perhaps some
isolated tstms flare up S of the state line late overnight as
the LLJ veers, but severe weather would be unlikely.

&&

.DISCUSSION...
Issued at 330 PM CDT Sun May 19 2024

Today has been a tricky forecast. As hinted by some of the
near-term models, an isolated supercell has developed in
northern Kansas. This has turned eastward and is JUST south of
our forecast area in Russell County as of 330pm. This storm will
be capable of all severe hazards (tornado, wind, very large
hail) as it slowly meanders eastward over the next few hours.

In addition to this, convection contuse to develop in southwest
Kansas and eastern Colorado. High-resolution models show this
activity continuing to develop into one or more west-east
propagating squall lines capable of dangerously strong winds
(75+ MPH). That said, the WoFS (Warn on Forecast System) has
been keeping the bulk of this activity south of our area
entirely.

Additional convection over the Nebraska panhandle could push
into central Nebraska later this evening, but should be on an
overall weakening trend. In fact, some of the latest HRRR runs
have this activity completely dissipating before it reaches us.


Monday will bring another risk for severe storms to the area.
There is still plenty uncertainty on exact details regarding
coverage and exact location, but it appears that the timing will
favor the later side, with some models (notably the NAMnest)
bringing us little to no convection until after midnight. Strong
deep-layer shear (40-50kt) will allow for a continued severe
threat with any storms that develop into the early morning hours
of Tuesday.

A few thunderstorms could redevelop Tuesday morning and early
afternoon as a cold front moves through the area. Gusty
northwest winds will arrive behind this front, and drier
conditions are also expected to return Tuesday evening through
Wednesday.

The upper pattern remains fairly busy through next weekend, with
continued chances for rain and thunderstorms. Above-normal
precipitation continues to be favored through the Memorial Day
weekend before possibly turning a bit drier as we head into
June.

&&

.AVIATION /00Z TAFS THROUGH 00Z TUESDAY/...
Issued at 655 PM CDT Sun May 19 2024

LOW confidence TAF cycle given uncertainties with CIGs and VSBYs
due to convection in the region.

Have removed any mention of VCSH or VCTS as it appears any
activity will remain pretty far W/S of the area tonight. While
that is one aspect of the forecast that have come into some
clarity, the late overnight trends for stratus and/or fog have
not. In general, models have been trending towards more stratus
and perhaps even some light fog - neither of which seem
unplausible given a period of lgt (and somewhat variable) low
level flow ahead of a front, and recent rainfall both locally
and upstream to the S. Didn`t feel comfortable carrying a VFR
TAF all night, so leaned towards the IFR stratus as being more
likely than IFR/MVFR VSBY`s, but will have to closely monitor
trends for potential amendments. Appears stratus could linger
into at least mid to late AM as CIGs rise to MVFR, then scatter
out some for the aftn.

Winds will generally remain out of the S this eve, then bec lgt
and vrbl for a time before veering to the SW/W after 06Z, then
NW towards dawn behind a weak front. N-NNE winds around 7-11kt
look to prevail late AM thru the aftn. Confidence on wind is
medium.

&&

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

&&

$$

UPDATE...Thies
DISCUSSION...Mangels
AVIATION...Thies