233
FXUS63 KGID 052058
AFDGID

Area Forecast Discussion
National Weather Service Hastings NE
358 PM CDT Sun May 5 2024

.KEY MESSAGES...

- Enhanced risk for severe thunderstorms Monday
  afternoon/evening. All forms of severe weather will be
  possible, including tornadoes. Thunderstorms may initially
  develop as supercells across our western zones and then become
  more linear and more widespread as they track east across our
  eastern zones likely transitioning into a QLCS with bowing
  line segments.

- There will be additional periodic small chances (20-30%) for
  showers and non-severe thunderstorms Tuesday night through
  Thursday night. However, most areas will see the period after
  Monday evening as a period of drying out with generally only
  isolated light rainfall events (<0.10") through the remainder
  of the forecast period.

- Temperatures will be fairly close to normal through the 7-day
  forecast period with highs generally in the upper 60s to
  lower 70s.

&&

.DISCUSSION...
Issued at 227 PM CDT Sun May 5 2024

Tonight...

Low clouds will develop and overspread much of the area. Can not
rule out a light passing rain shower or drizzle after midnight,
but overall not expecting much in the way of precipitation until
the main show gets going late Monday morning into Monday
afternoon. Therefore, lowered overnight and early morning rain
chances.


Monday (Enhance Risk Severe Weather)...

The SPC Enhanced Risk of severe weather remains in place for the
forecast area tomorrow from generally I-80 south with the slight
risk across our northern zones. A large negatively tilted upper
trough will enter the plains with a closed 500 mb low over
western South Dakota. A cold front/dry line will extend south
across Nebraska/Kansas with moist 60 degree dewpoints ahead of
the front and drier 20 and 30 degree dewpoints behind the front.

What We Know (Highest Confidence)...
Forecast models are in good agreement that thunderstorms will
eventually form along the eastward moving dry line/cold front
between Noon and 3 PM west of Highway 281 and then track east
northeast through the afternoon and evening hours. The most
likely time frame for the storms to reach Highway 281 will be
between 3-5 PM, and then they will likely exit our eastern zones
between 6-8 PM. Timing could shift some, so please keep up to
date with the latest forecast, but this is the current forecast
model consensus. Thunderstorms will initially be more discreet,
but are likely to form into a line/QLCS bringing more widespread
precipitation to eastern areas. The storms should be progressive
enough/quickly moving that rainfall amounts for most areas
should be under 1 inch, but can not rule out some localized
higher amounts especially southeastern areas.

What we don`t know (Lower Confidence)...
There is some question regarding how quickly the low clouds will
scatter out and even if all areas can scatter out before the
frontal passage. If we are slow to see late morning/early
afternoon sunshine, then the severity and coverage of the
storms will decrease as instability will be more limited.
Southern areas are most likely to see more sunshine and thus
higher instability and greater severity threat. Another big
question will center around how quickly the storms transition
from discreet supercells into a line/QLCS. Larger hail and
tornadoes will be more likely if the storms can remain discreet
longer, but most model guidance rather quickly transition the
the storms into a line across our forecast area. More discreet
thunderstorms seem most likely further south into Kansas south
of our forecast area where instability will also be higher.


Tuesday through Thursday...

The upper trough will just meander across the central plains
through Thursday, but will be cut off from the better low level
moisture after Monday. Therefore, we could still see a few light
rain showers or isolated thunderstorms periodically between
Tuesday night and Thursday night, but most locations will be dry
and those that do see precipitation will likely only see rather
minor amounts. Highs will generally be in the upper 60s to
around 70.


Friday through Sunday...

We should see an upper level ridge develop across the western
United States, which will be a drier pattern for us. Therefore,
we have no rain in the forecast for next weekend at this time.
Temperatures should remain mild in the upper 60s to around 70 on
Friday, but could warm into the mid to upper 70s by Sunday.


&&

.AVIATION /18Z TAFS THROUGH 18Z MONDAY/...
Issued at 1240 PM CDT Sun May 5 2024

We`ll see scattered low to mid clouds today, but should remain
VFR through at least most of the evening hours. However, we do
expect increasing low clouds after midnight including IFR
ceilings that could persist through a majority of Monday
morning. There also could be a few sprinkles or vicinity rain
shower Monday morning, with the better chance for thunderstorms
holding off until Monday afternoon.

&&

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

&&

$$

DISCUSSION...Wesely
AVIATION...Wesely