665
FXUS63 KGLD 191106
AFDGLD

Area Forecast Discussion
National Weather Service Goodland KS
506 AM MDT Sun May 19 2024

.KEY MESSAGES...

- Showers and some storms look to continue through mid morning.

- Severe storms remain forecasted for today with hail around two
  inches in diameter and wind gusts around 70 mph possible.

- Storms; some severe north of Interstate 70 are forecast
  Monday. Main hazards are large hail, damaging winds and
  torrential rainfall.

- Cooler with frost concerns mid week.

&&

.SHORT TERM /THROUGH TUESDAY NIGHT/...
Issued at 244 AM MDT Sun May 19 2024

Showers and storms continue to push off to the east; some continued
isentropic lift will continue to support the potential for some
redevelopment behind the main batch of rain through at least mid
morning. Will be monitoring for some fog and stratus potential this
morning as well due to the newly saturated boundary layer and
anticipated waning winds.

The focus then turns to the severe weather potential today. A warm
front will move northward throughout the day along with a dryline
developing near the Palmer Divide during the early afternoon which
will push eastward. Currently it appears there will be 2 favored
areas for severe thunderstorm development.

1) Along the dryline in eastern Colorado and into NW Kansas/SW
Nebraska: Fairly confident in convective initation along the
dryline as CAMS have been fairly consistent with initation in
this area for the past 24 hours and HREF paintball support this
as well. The concern will be the magnitude and the coverage of
storms. Recent runs of the HRRR have backed off on the intensity
and keeps coverage to a storm or two; whereas the NAMNEST and
some MPAS guidance has more intense storms and/or develops more
of a cluster of storms. I`m continuing to favor the NAMNEST as
it has consistently done the best this spring thus far. The MPAS
guidance also does make sense as well given the clustering of
storms as overall 0-6 shear doesn`t look as impressive as last
night now showing 25-30 knots vs the 35-40 knots that was seen
last night. The 25-30 knots of bulk shear would favor more of a
cluster solution. As for hazards for this area I do think that
large to isolated very large hail and damaging winds (especially
if more of a clustering forms). Not as concerned for very large
hail as I was the past few nights given the lesser amounts of
bulk shear and the potential for more competing updrafts. That
being said if a discrete/dominant storm does form do think that
potential would be there for 2+ inch hail due to MUCAPE being
over 3000 j/kg and very steep lapse rates.

2) SE portions of the CWA (southern/eastern Wichita, southern Logan,
southern Gove counties):  signal for initation has been very
consistent with rapidly intensifying cells occurring across SW
Kansas and growing upscale as it moves ENE across Kansas. Confidence
is a bit low with how much of the CWA this will affect. Do think the
main concern with this would be damaging winds in excess of 70
mph along with some hail potential. Very good overall signal for
a bow echo to develop across East Central Kansas and into
Central Kansas; again the question will be how big of a
footprint (if any) will it have on our CWA.

Temperature wise for the day is a little tricky especially if
stratus/fog does develop and/or if cloud cover lingers. I continue
to trend in the low 80s for northeast portions of the area as this
will be the relative better chance of the above variables affecting
the temperature. A warm front will also be lifting north
through out the day, so if that does surge north a bit quicker
than anticipated each locale may be about 5 degrees to cool as
some low 90s would be in the realm of possibility. Behind the
dryline some near critical fire weather conditions still remains
possible but should be confined to western portions of Cheyenne
county Colorado. GFS forecast soundings which typically does
best with mixing potential keeps winds around 20 knots for the
duration of the afternoon; although some rogue gusts in excess
of 25 mph may be possible especially later in the afternoon,
will forego any fire highlights due to sporadic nature of the
gusts.

Sunday night into Monday morning will see another surge of moisture
from the south. Guidance is also picking up on some fog potential
within the vicinity of a developing surface low across SW Kansas,
where winds will be more light and variable. There is enough signal
for fog that have introduced patchy fog across the eastern counties
with some dense fog possible at times.

Monday will see another potential for severe weather across the
Tri- State area. A longwave trough from the SW CONUS will eject
another wave out onto the Plains during the late
afternoon/early evening hours. The main wave does look to eject
a bit further north which should keep any severe threat north of
Interstate 70 and may not even happen until after sunset. Some
large hail threat up to ping pong ball, and perhaps some tornado
threat may develop as the LLJ interacts with the developing
MCS. Very heavy rainfall does appear possible with this activity
as well with 1-1.25 PWAT value. The continued additional lift
from the LLJ may support some backbuilding potential which may
increase the excessive rainfall threat but the continued signal
for very quick Corfidi vectors should keep any flood threat to a
minimum.

Temperatures for the day appear to be a  bit challenging as status
or fog may linger through the day. Started a trend to lower
temperatures with a conshort/NAM blend to get temperatures into the
low 70s to low 80s across the area. But if the stratus indeed does
hold strong then temperatures may be about 10 degrees to warm.
Before I get that aggressive with temperatures want to see more
consistency than two models showing this.

Tuesday, a cold front looks to move across the area with another
potential for rainfall. The severe threat currently doesn`t look as
favorable mainly due to a lack of instability. Showers/storms look
to develop along and behind the front. GFS is showing a 10-15 mb
pressure rise over 3 hours which may support some strong to damaging
wind threat especially if precipitation is ongoing due to
downward momentum transfer. Continue to watch the potential for
frost across Colorado counties and perhaps as far east as the
Highway 27 corridor Wednesday morning but continues to be
dependent on quickly cloud cover does move out of the area.

&&

.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
Issued at 215 AM MDT Sun May 19 2024

Broad southwesterly flow continues across the central CONUS
through the entire long term period. Embedded shortwave troughs
will provide near daily chances for mainly afternoon and evening
showers and thunderstorms. Severe chances appear rather limited
however, mainly due to a lack of instability. The one exception
might be Thursday, with decent moisture return resulting in
instability of 1000-2000 j/kg by the afternoon. However,
Thursday is also the day with the lowest deep layer shear, 20-30
kts, so that may limit any severe potential. For Wednesday and
Friday, very little instability, either surface based or
elevated, is forecast for the area. There is some weak
instability by Saturday, along with very good deep layer shear,
which may result in low probabilities for severe storms.

Temperatures through the period show some minor fluctuations
associated with occasional frontal passages. The coolest day
will be Wednesday with lower 70s, and the warmest will be
Thursday with low to mid 80s, then 70s and 80s for Friday and
Saturday. Some patchy frost possible Wednesday morning in
Colorado with upper 30s currently forecast for lows.

&&

.AVIATION /12Z TAFS THROUGH 12Z MONDAY/...
Issued at 502 AM MDT Sun May 19 2024

Seeing some signs of stratus developing in between
showers/storms that are currently moving across the area so do
have some periods of MVFR ceilings in for each terminal. After
this main batch of storms that is currently impacting KMCK
moves through some additional hit and miss showers look to
develop so will maintain a VCSH for KGLD. Focus then turns to
thunderstorm threat this afternoon. Guidance has been struggling
with coverage for this afternoon but has consistently been
placing a storm near KGLD so will continue with the VCTS. For
KMCK, it is a bit more uncertain so will have to monitor trends
for the 18Z TAFS. A signal for fog and/or stratus is presenting
itself for the latter portion of this TAF period for KMCK so
have introduced MVFR ceilings and visibilities for now; this
potential should remain east of KGLD.

&&

.GLD WATCHES/WARNINGS/ADVISORIES...
KS...None.
CO...None.
NE...None.

&&

$$

SHORT TERM...Trigg
LONG TERM...024
AVIATION...Trigg