503
FXUS63 KGLD 060442
AFDGLD

Area Forecast Discussion
National Weather Service Goodland KS
1042 PM MDT Fri Jul 5 2024

.KEY MESSAGES...

- Severe weather chances return for the weekend. Tomorrow could
  see severe storms develop with all hazards possible.

&&

.UPDATE...
Issued at 813 PM MDT Fri Jul 5 2024

Overall forecast remains on track. Did increase pops into the
likely category (54+%) across the east for tomorrow as guidance
has remained consistent with initiating and ongoing convection
into the afternoon. Do continue to still have concerns for 2+
inch hail although EBWD is lacking but still think that 8.5+ C
lapse rates can overcompensate.

Sunday morning, another consistent signal for training showers
and storms perhaps into the afternoon. There may be some hydro
concern that develops as this will be over the same area that
looks to see the severe storms from tomorrows system. Due to
middle of the road corfidi vectors (30-40 knots) and PWATS
around 1.4-1.5 inches don`t think a widespread hydro issue will
be on the table but some localized concerns. Looking at the 12Z
EFI, it was also highlighting this same area for anomalous
values of qpf as well. Will need to keep a close eye on this
over the next few shifts.

&&

.SHORT TERM /THROUGH SUNDAY NIGHT/...
Issued at 152 AM MDT Fri Jul 5 2024

Across the region this afternoon, skies are a mix from partly sunny
east to sunny conditions west. The big differences is due to
lingering showers that are a carry over from this morning as a weak
700mb trough passed through the area. High pressure still remains at
the surface, allowing for a light yet variable wind for most, with
temps as of 100 PM MDT mainly in the 70s with some spot 60s where
clouds are more prevalent.

The main wx concerns in the short term period will focus on the
threat for severe wx Saturday and again on Sunday. Also some
elevated fire wx potential over portions of northeast colorado.

Upper ridge remains over the western portion of the country per the
latest RAP40 500mb analysis, providing a NW flow aloft. For the
remainder of today and into the evening hours, expecting a slow
clearing from west to east as the aforementioned surface ridge
shifts east of the CWA. Some weak instability along the northern
tier zones may trigger a few rw/trw (15-20%) around 09z-12z Saturday
before moving east.

Much of the remaining morning hours Saturday will be decent as we
await the arrival of a dryline setting up west and pushing slowly
east into the afternoon hours. Guidance is mixed as to the position
of the dryline going into the afternoon hours. This will pay a key
role in the next round of convection set to initiate between 17z-19z
Saturday, in tandem with a passing shortwave that rides down the
eastern side of the upper ridge.

The latest NamNest is showing convection starting around the midday
timeframe and progressing fairly quickly south and east and possibly
exiting by 00z Sunday with some lingering rw/trw thereafter. SPC
continues to carry a Slight Risk for severe east of the Colorado
border and a Marginal west, and will highly depend on where the
dryline ends up. Looking for SBCape around 21z-00z to range from
about 900j/kg to start but increasing to around 2000j/kg thereafter.
DCape is around 1400-1500j/kg. Could see some severe hail around 1-
2" at the start of convection but eventually transition to a wind
threat 60-70 mph as the convection moves through the CWA as a line.
Some low chances for a landspout along the dryline, but orientation
to storm motion is off.

The other concern for Saturday will be in northeast Colorado behind
the dryline. RH values will dip into the mid and upper teens with
winds staying below criteria. Nonetheless some elevated/near
critical fire wx conditions are possible, especially for western
portions of Yuma/Kit Carson/Cheyenne counties.

Guidance has a broader trough swinging through the CWA overnight
into Sunday, with a surface low developing along the west side of
the dryline remnants, moving south through Colorado. Easterly flow
sets up overnight Saturday and eventually more of a northeasterly
fetch going into Sunday. A front stretching east from the low will
be the focus for additional convection late Saturday and through
Sunday evening, with a shift of highest pops south as the day
progresses closest to the low/front.

Conditions in place for another potential round of strong to severe
storms starting in the afternoon. Looking for decent instability to
ensue with daytime heating. SBCape/MLCape values will range from
2500-2700j/kg around 21z-00z with DCape decent around 1000-1100j/kg.
As a result could see storms with a wind and hail threat through the
afternoon hours, possibly trailing into the early evening. SPC
currently carries a Marginal risk for most of NW Kansas. Guidance
shifts pops/precip southward with the low movement overnight Sunday,
tapering rain/storms chances from north to the south, ending by 12z
Monday. Locally heavy rainfall is also possible Sunday with PW
values ranging around 1-1.2 inches.

For temps, highs for the upcoming weekend will range widely as
Saturday will have upper 80s to lower 90s, but give way to mid and
upper 70s for Sunday. Overnight lows each night will range mainly in
the 50s, with warmest areas east of Highway 25. Some spots east of
Highway 83 Saturday night could only drop to near 60F.

&&

.LONG TERM /MONDAY THROUGH FRIDAY/...
Issued at 1211 PM MDT Fri Jul 5 2024

Current runs of the GFS and ECMWF are continuing to show a broad
amplified 500mb ridge over the western portion of the country on
Monday that will eventually shift slowly eastward by Friday. At the
surface, the shifting of the upper ridge during the week will allow
for a ridge to set up east of the area during this time, with a
surface trough to our west. The trough does extend into the CWA
Tuesday night through Wednesday night in tandem with a weak
shortwave working through the east side of the upper ridge. This
could give a 15-20% for trw/rw during this time, otherwise dry
weather is expected. The focus for storms Tuesday night and
Wednesday will be the entire CWA, but shift to along/south of the
Interstate for Wednesday night.

With the lack of moisture during the extended period, a return to
near and above normal highs is expected area-wide as 850 temps
Tuesday will range +24c to +28c with a range by Friday around +28c
to +32c. This will be aided in part by southerly surface flow on the
non-precip days.

For temps, highs on Monday are expected to range in the upper 70s
west into the mid 80s east, but will give way to upper 80s through
the mid 90s from next Tuesday onward. Hottest day will be on Friday,
mainly east of the Colorado border. Overnight lows will have a
similar trend with mid and upper 50s Monday night give way to lower
and mid 60s by the end of the week. Warmest locales will be east
Highway 25.

&&

.AVIATION /06Z TAFS THROUGH 06Z SUNDAY/...
Issued at 1035 PM MDT Fri Jul 5 2024

VFR conditions continue to remain forecasted for each terminal.
Do have a slight concern for fog developing near KMCK as dew
points are currently running around 5-7 degrees higher than
guidance which is creating low dew point depressions. This along
with light winds, clear skies and recent rainfall for today
would normally be enough for at least patchy fog to develop
across the area; however with no guidance supporting this not
enough confidence to identify an exact time frame for when this
may occur. Did add in a tempo for KGLD as the RAP does support
some lower 850mb moisture working in with some stratus possible,
winds do look to remain breezy enough that I don`t think fog
will be of concern for the terminal.

Continue to monitor for severe storm development near each
terminal Saturday afternoon. Exact location on dryline
placement does still exist mainly for the KGLD terminal, but do
think a slight westward push of the dry line may occur which
does leave enough confidence to keep the PROB30 in play. As for
KMCK, initiation does look to be close enough to the terminal
at this time that a slightly more northern initiation would
have the terminal impacted so have left the PROB30 as well.

Winds will then turn to the southeast Saturday evening/night as
additional moisture advects in leading to shower and storm
potential just after the end of this period.

&&

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

&&

$$

UPDATE...Trigg
SHORT TERM...JN
LONG TERM...JN
AVIATION...Trigg