253
FXUS63 KGLD 161506
AFDGLD

Area Forecast Discussion
National Weather Service Goodland KS
906 AM MDT Fri Aug 16 2024

.KEY MESSAGES...

- Low chance for severe weather this morning and afternoon.

- Drier and warmer going into the weekend.

- Some uncertainty with next week`s pattern, but currently could
  favor above average temperatures to begin the week.

&&

.UPDATE...
Issued at 903 AM MDT Fri Aug 16 2024

Update to forecast issued to account for the lingering band of
light to moderate showers along the Highway 36 corridor from
Atwood east. Decent rainfall amounts so far in those locales,
some of which are approaching 0.50-1.00". Latest radar imagery
showing these are weakening some, but could linger for another
hour or so. The SE corner of the CWA is still seeing scattered
showers, with the heavier/stronger activity already moving east
of the area.

&&

.SHORT TERM /THROUGH SATURDAY NIGHT/...
Issued at 205 AM MDT Fri Aug 16 2024

For the short term period, the main focus is on the severe weather
threat today. While severe weather chances are low overall, they may
be a bit more impactful with chances during the morning hours and a
chance for significant severe weather this afternoon. Otherwise,
benign conditions are forecast for the rest of the period.

Current observations show an upper ridge beginning to amplify over
the Western Rockies while mid-level moisture moves over the area
from the northwest flow. Guidance is suggesting that a 700mb
shortwave is currently moving towards the area from the west. With
the ongoing showers and storms, this seems likely and will help
continue to generate showers and storms through the morning hours.
Most storms will be sub-severe, especially through sunrise with
current MUCAPE below 500 J/KG and lapse rates generally 7 C/KM
or less. Around and after sunrise, MUCAPE could increase to 1000
J/KG with effective shear around 45 kts, allowing a small
chance for a stronger storm to develop. If it holds together
long enough, hail around 1 to 1.5 inches would be possible. As
the storms move on, they will be in an environment with DCAPE
greater than 1000 J/KG, downshear vectors around 50kts and upper
cloud level winds around 50 kts. This could allow for a couple
gusts to 60-65 mph, especially if storms ride along an outflow.

Once the morning storms move on and dissipate (as the 700mb wave
dissipates), skies should clear and temperatures warm into the low
90`s with 850mb temps in the upper 20`s C. Winds should remain
relatively light around 10 mph or less with a broad pressure
gradient, though the direction may vary at times as lower pressure
tries to form in Eastern Colorado.

This afternoon, there`s an 85% chance that skies remain clear and
winds just slowly lower through the evening. However, if
temperatures become warm enough and the cap erodes, a supercell
(maybe two) could develop near the CO border near a weak surface
convergence zone. If the supercell does develop, significant severe
weather would be possible with MUCAPE around or greater than 2000
J/KG, 50-55 kts of effective shear, downshear vectors around 60kts
and upper storm winds around 70kts. Currently messaging hail up to
2.5 inches (mid level lapse rates are forecast to be around 7 C/KM)
and wind gusts up to 75 mph. The storm would move southeast through
the area through the late afternoon hours.

This evening and into tonight, skies are forecast to be clear and
winds lighten as the upper ridge axis continues to move closer to
the area. Lows are forecast to drop to around 60.

Tomorrow, sunny skies and warm temperatures in the low to mid 90`s
are forecast with the ridge axis moving more over the Eastern
Rockies and relatively dry air forecast to be over the area. There`s
still a 10% chance for a shortwave to move through and produce some
showers near the Tri-State border, but the weak forcing, broad
subsidence, and lack of moisture really keep the chances low.
Tomorrow evening and night, the low level flow is forecast to be
from the southeast which will bring moisture to the area, but likely
too late to produce storms with no forcing over the area. The
moisture increase should keep lows a bit warmer in the mid 60`s.

&&

.LONG TERM /SUNDAY THROUGH THURSDAY/...
Issued at 230 AM MDT Fri Aug 16 2024

The main upper feature will be an upper ridge extending from the
Four Corners northeast into the central Plains. Due to the
orientation of the ridge, there will be near daily chances for
showers and thunderstorms which will be moving along the western
periphery of the ridge. Chances will be confined to mainly
Colorado in the afternoon where they will develop, then the
rest of the area during the evening hours, with better chances
weighted in the west. Instability appears to be fairly limited
through the period, but deep layer shear will be 30-40 kts each
day, suggesting at least the occasional marginal or slight risk
for severe storms. Temperatures will be above normal through
the period, generally in the 90s for highs and 60s for lows,
though an occasional day of triple digit heat will be possible,
especially south of Interstate 70.

&&

.AVIATION /12Z TAFS THROUGH 12Z SATURDAY/...
Issued at 538 AM MDT Fri Aug 16 2024

For KGLD... With the line of storms past the terminal, the rest
of the morning hours are forecast to be VFR with clearer skies.
Any additional development this morning should be a county north
of the terminal. The next time period to look out for is around
20-23Z as there is a 15% chance that a storm could develop and
turn into a supercell. Due to the low confidence, it is not in
the TAF, but look for updates in later issuance. Otherwise,
winds should remain around 8-12 kts through the day before
weakening late in the night around 08Z.

For KMCK... VFR conditions are forecast for the period, though
the rain and occasional thunderstorms should linger around the
terminal through about 15Z (but as late as 18Z). As of writing
this discussion, radar was still showing showers and storms 3
counties over, moving toward the terminal. In short, expect a
rainy morning. The good news is that most of the rain is
reported to be light and ceilings should stay above 3000ft. Once
the rain passes, clear skies are forecast with winds lightening
through the evening and overnight hours.

&&

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

&&

$$

UPDATE...JN
SHORT TERM...KAK
LONG TERM...024
AVIATION...KAK