406
FXUS63 KGLD 110705
AFDGLD

Area Forecast Discussion
National Weather Service Goodland KS
105 AM MDT Sat May 11 2024

.KEY MESSAGES...

- Showers and thunderstorms are forecast for this weekend.
  Severe weather over the weekend is not expected at this time.

- Severe weather potential may return by the middle of next
  week.

&&

.SHORT TERM /THROUGH MONDAY NIGHT/...
Issued at 141 PM MDT Fri May 10 2024

A 500 mb low pressure system is still stalled out over the
Great Basin. This afternoon and into the evening, this will send
out a weak shortwaves across the Great Plains, creating enough
forcing to start some light precipitation, but not enough for
anything organized or severe. Until about 0-3Z this evening,
light showers will be over eastern Colorado, mostly just
creating virga as there is a moderately pronounced dry layer
near and above the surface. Some light rain accumulation is not
entirely out of the question for these locations, but anything
more than a hundredth or two is unexpected. These light showers
could spill over into far western Kansas, but confidence of this
occurring is less than 20%.

Saturday afternoon and into the overnight hours look to be a
different story as the low pressure system starts moving to the
east. This will provide enough forcing for some slightly more
organized precipitation, including a few thunderstorms. The
threat for severe weather is low, but not 0. MUCAPE looks to be
limited to around 300-800 J/KG and effective shear is about
15-20 kts or less. This could lead to some pop-up storms that
are quickly lived. Before about 0Z Sunday, any storm that
rapidly grows in an area of higher CAPE could burst out, so we
will need to keep an eye out for strong winds with decaying
storms tomorrow.

Sunday afternoon looks to be the "best" chance in the short-
term for some impactful precipitation and severe storms,
although no parameters look very impressive. A weak 850 mb lee
low is expected to form in the very early morning hours Sunday
and move across the CWA in the mid-day. Supplied with a 20-35
kts LLJ, we will have plenty of moisture to work with, which
does cause some concern for flooding potential. However, due to
little rainfall over the previous week and soundings show
upshear speeds around 20-25 kts (a little fast for flooding),
there is only about 5-10% confidence flooding would occur. PWATS
are near 1 inch and there is an fairly elevated freezing level
which adds to the confidence, but does not make it certain. CAPE
looks to be around 1,000-1,500 J/kg with EBWD shear around
25-30 kts, making low-end severe storms possible (~5% chance).

Saturday looks to warm into the upper 60s and 70s, however
cloud cover could lower these temperatures 3-5 degrees if the
clouds become more widespread and move farther east early.
Sunday will be cooler with highs in the mid 60s to low 70s, due
to the low pressure system moving a cold front across the area.
Tonight will cool into the 40s; some locations in eastern
Colorado could see upper 30s if the clouds clear out early and
the winds become calm. Tomorrow night will be warmer as the LLJ
will be moving warm, moist air into the region. The western CWA
will remain in the mid 40s but the eastern CWA looks to stay in
the mid 50s. Sunday night will be slightly cooler behind the
cold front, likely down into the 40s to low 50s.

&&

.LONG TERM /TUESDAY THROUGH FRIDAY/...
Issued at 105 AM MDT Sat May 11 2024

For Tuesday, still forecasting a warm and potentially active day
with weak ridging ahead of an advancing upper trough. With the
ridging and generally westerly flow, warmer air is forecast to be
over the area with 850mb temps supporting highs in the low to mid
80`s. During the afternoon and evening hours, an area of low
pressure is forecast to develop over the area with a broad area of
surface convergence. This will provide an initiation point for
storms during the afternoon and evening hours. There could be severe
weather, though the effective shear is still generally forecast to
be below 30kts with the generally weak flow over the area. What
could allow severe weather is MUCAPE could reach 1500 J/KG and is
forecast to be uncapped. Currently the main threat would be hail
around an inch, but could turn more into a heavy rain and small hail
threat if shear stays closer to 20 kts and the surface convergence
remains broad.

Wednesday and beyond is more uncertain as guidance shows a large
spread in what becomes of the upper pattern. Even with the
uncertainty, it looks like Wed/Thu will be transition days similar
to the past few days as it is suggested that there will be another
larger wave moving east while a cut-off low trails over the Western
CONUS. It`ll just be a matter of how quickly it pushes off.
Currently have temps near average and some slight chance for
precipitation if smaller disturbances move through. Friday will
depend if the the progression of the upper pattern is slow (and
allows some ridging for warmer temperatures) or is quick and turns
more into a broad trough (probably near average temperatures). In
either case, there will still be some small chances for
precipitation as the upper flow would either be westerly or
northwesterly.

&&

.AVIATION /06Z TAFS THROUGH 06Z SUNDAY/...
Issued at 1015 PM MDT Fri May 10 2024

GLD: VFR conditions will prevail through the day on Saturday.
Expect mostly clear skies overnight through Saturday morning,
with ~4-5 KFT AGL ceilings developing Saturday afternoon.. when
showers may approach the terminal from the south. Sub-VFR
conditions associated with showers (perhaps a storm) are
expected near the end of the TAF period (00-06Z Sunday). Light
and variable winds will prevail overnight. Winds will shift to
the S-SSW late Saturday morning.. increasing to ~12-17 knots
during the afternoon.

MCK: VFR conditions will prevail through the TAF period.. with
ceilings confined above ~8 KFT AGL. Light and variable winds
will prevail overnight. Winds will shift to the S-SSW late
Saturday morning.. modestly increasing to 10-15 knots during the
mid-late afternoon (~21Z).

&&

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

&&

$$

SHORT TERM...CA
LONG TERM...KAK
AVIATION...BV