564
FXUS63 KGLD 061053 CCA
AFDGLD

Area Forecast Discussion...CORRECTED
National Weather Service Goodland KS
453 AM MDT Thu Jun 6 2024

.KEY MESSAGES...

- Dry conditions are forecast for today with only a slight
  chance of showers and storms tonight for areas south of I-70.

- Friday and Saturday bring back chances for severe weather in
  the area. Friday has the higher chance for severe weather with
  large hail, wind gusts to 70 mph, and maybe a tornado
  possible. Friday is also forecast to have highs in the 90`s.

&&

.SHORT TERM /THROUGH SATURDAY NIGHT/...
Issued at 213 AM MDT Thu Jun 6 2024

For the short term, relatively calm conditions today will be
followed by more active weather going into the weekend.

Today, the area is forecast to remain in northwest flow aloft
with a ridge over the Western CONUS and a trough over the Great
Lakes. With some slightly cooler air moving into the area, highs
today will likely round out in the mid 80`s in spite of another
day with sunny skies. Winds will remain generally from the
east, but pick up more of a southeasterly component later in the
day. For tonight, most of the area north of I-70 is forecast to
see mostly clear skies. For locales south, the southeasterly
flow in the low levels is forecast to bring some more moisture
for the southern half of the area. With the additional moisture,
a few showers and storms may be able to form in Eastern
Colorado if a shortwave moves through and/or with some slight
upslope flow. Severe weather is unlikely with CAPE forecast to
be below 2000 J/KG, little synoptic lift, and little to no
effective shear. Lows should mainly be in the 50`s, but
persistent cloud cover or effective moisture advection could
have some areas stay in the 60`s.

Tomorrow, the upper ridge over the west is forecast to
deamplify over the area and become more pronounced near the
Western Coast. This is forecast to happen as a smaller upper
low/trough moves through the Upper Plains. As this feature
slides through the Plains, it is forecast to move the lower
surface pressure from off the Front Range east into the Plains.
With the moisture return from the prior night, the advancing
surface low is forecast to trigger storms during the afternoon
and evening hours (generally after 21Z). Similar to prior events
like this, storms should form over Eastern Colorado and move
east across the area. The environment in Eastern Colorado may
not be as favorable for severe weather with weaker shear and
drier air due to the surface low`s advancement. If so, storms
would likely be marginally severe at best and begin to cluster.
The question then is how much moisture and instability remains
as the storms and low pressure system move east. If prior events
are a good guide, then enough moisture and instability should
be present to allow for continued severe storms chances across
the area and through the evening. Will also have to watch for
flooding. If the clusters move through as forecast with the
system, 1 to 2 inches would be reasonable in some spots, but not
enough for flooding. However, if training occurs or a cluster
forms ahead of the main convergence zone with the low, two
rounds or more could move through and pose a flooding risk. In
terms of temperatures, the southerly flow will help temperatures
warm back into the 90`s. Some locales south of I- 70 may even
get close to 100.

Saturday, the area is forecast to be in zonal to northwest flow
aloft with very little discernible features near the area. The
area should also be in slightly higher pressure with post
frontal air. This is forecast to keep temperatures cooler in the
upper 70`s and 80`s. With moisture still forecast to linger in
the area (the drier air looks to retreat back overnight Friday),
showers and storms will again be possible during the afternoon
through early overnight hours. Based on current guidance,
instability and shear are a little lacking with the main
synoptic driver forecast to be a shortwave that moves through
the flow. But a severe storm or two could be possible.

&&

.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
Issued at 300 AM MDT Thu Jun 6 2024

GFS/ECMWF long range guidance suggest that the main belt of
mid-latitude westerlies (and majority of progressive shortwave
energy) will be relegated to higher latitudes.. mainly over the
Pacific Northwest, northern Rockies, Dakotas and Upper Great
Lakes (40-50N).. and that a stagnant flow pattern will prevail
at lower latitudes, over the Desert Southwest, 4-Corners,
central/southern Rockies and Central/Southern Plains.. where
several waves may be trapped /cut-off/ within.

If the Tri-State area is indeed situated on the far southern
fringe of the westerlies, one would expect ~climatological
conditions. It should be noted that.. increased pattern
complexity (e.g. the presence of one or several cut-off waves
invof the southern Pacific Coast, Desert Southwest, 4-Corners
and/or Southern Plains) drastically reduces forecast
confidence.. especially at this range.

&&

.AVIATION /12Z TAFS THROUGH 12Z FRIDAY/...
Issued at 449 AM MDT Thu Jun 6 2024

For KGLD & KMCK... VFR conditions and surface winds below 10 kts
are forecast through the period. The only potential concerns are
for LLWS to develop tonight around 06Z and maybe some showers
over KGLD also around 06Z. Both are currently low enough chance
to not include in the TAFs.

&&

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

&&

$$

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