088
FXUS63 KGLD 172016
AFDGLD

Area Forecast Discussion
National Weather Service Goodland KS
216 PM MDT Mon Jun 17 2024

.KEY MESSAGES...

- There is a slight risk for severe thunderstorms this afternoon
  and evening from Yuma County in Colorado east along the Kansas
  and Nebraska border area. A cold front will be in this area
  and any thunderstorm that develops will be capable of
  producing large to very large hail, damaging winds and a
  tornado or two. Elsewhere, there is a marginal risk for severe
  thunderstorms, but confidence is low that they will develop
  and they would be isolated.

- Critical fire weather conditions are expected this afternoon
  and early evening in Kit Carson and Cheyenne counties of
  Colorado where low humidity and gusty winds will develop west
  of the dry line.

- Very windy conditions are anticipated along the Kansas and
  Colorado border area this evening and continue into the
  overnight hours. South winds gusting up to 65 mph will be
  possible. Some blowing dust is possible from late afternoon to
  the early evening in this area.

- There is a marginal to slight risk for severe thunderstorms
  from late Tuesday morning through Tuesday afternoon along and
  east of a Norton to Leoti line in northwest Kansas as a cold
  front moves through. A few storms may be capable of producing
  large hail and damaging winds.

- Heavy rainfall and flash flooding will be possible Tuesday
  night. The heaviest rainfall is expected to occur along and
  south of a Norton to Tribune line in northwest Kansas, but
  heavy rainfall cannot be ruled in the remainder of northwest
  Kansas and southwest Nebraska as well. Lowest rainfall amounts
  will be in northeast Colorado.

&&

.SHORT TERM /THROUGH WEDNESDAY NIGHT/...
Issued at 330 AM MDT Mon Jun 17 2024

The set up for today is very similar to yesterday. Southwest
flow continues aloft with another embedded shortwave trough
moving through in the afternoon and evening. The trough might be
a little stronger than yesterday. At the surface stationary
front will be in the northern Yuma County and eastward into
southwest Nebraska, but lifting north as a warm front in the
afternoon. A diffuse dry line will be trailing south from the
surface low in northeast Colorado along the Kansas and Colorado
border area. There will be a relatively short window when the
front will be in the forecast area which will complicate things,
as it will be the favored location for convective initiation.
Right now, looks like the front will be in the area through
about 21-22z before lifting out, so storms will have to
initiate before that time to tap into the favorable environment
near the front, which is what the NAMnest shows. Elsewhere,
cannot completely rule out isolated storms south along the dry
line which would move east into a moist and unstable
environment, but confidence is lower and mid level temperatures
may be too warm for the cap to break. Possible tornadic
environment will be along and north of the front, as well as
best parameters for very large hail as was seen yesterday. South
of the front, the environment is more marginal for hail and
wind, though the instability and shear do increase further east
should a storm get east of Highway 25. The other potential
hazard for today and especially tonight will be strong winds.
Low level jet strengthens near the Kansas and Colorado border
area after 00z and continues through about 09z. The core of the
LLJ is just off the surface, so despite unfavorable nocturnal
timing for mixing it will not take much to get those winds to
the ground. HRRR shows gusts in the 60-65 mph range for the area
where the High Wind Watch was issued. Blowing dust parameters
are briefly favorable early in the evening, but lapse rates not
as favorable by mid evening, so confidence is low in blowing
dust. Finally, with the dry and windy conditions west of the dry
line this afternoon, issued a Red Flag Warning for Kit Carson
and Cheyenne counties in northeast Colorado. Highs today will be
in the upper 90s to lower 100s and lows tonight in the 60s and
70s.

The surface cold front finally moves late tonight and will be
surging southeastward through the forecast area Tuesday morning,
stalling out across southwest and central Kansas Tuesday
afternoon. May see a few showers and thunderstorms develop along
the front as early as Tuesday morning, then in far southeast
areas Tuesday afternoon. There is a marginal risk for severe
storms with the front, though if the front is faster the risk
for severe storms may be south of the area. High temperatures
will range from the upper 70s well behind the front in northeast
Colorado to the lower 90s ahead of it from Hill City to Tribune
and south. Showers and thunderstorms will increase in coverage
Tuesday night as a shortwave trough moves through in the
southwest flow over the moist post frontal upslope environment
now in the forecast area. Heavy rainfall and flooding will be a
concern Tuesday night. Highest QPF will most likely be across
southern counties, from Norton to Tribune and south, where mean
QPF is around 1 inch but higher percentiles are between 2 and 3
inches. Even further north 1 to 2 inches will be possible in
northwest Kansas and southwest Nebraska, with lowest amounts in
Colorado with perhaps some local amounts up to 1 inch near the
Kansas border. Lows Tuesday night will be in the 50s to lower
60s.

Wednesday will be cool and cloudy with scattered showers and
isolated thunderstorms through the day. Instability will be very
limited across much of the area, though the front may drift
north into the southeast corner during the afternoon, Hill City
to Gove, with weak to moderate instability possible there but
weak shear at only 20 kts. There might be a marginal severe risk
in that area, but otherwise not anticipating severe storms. High
temperatures will be mainly in the 60s with the clouds and rain,
with some lower 70s across southeast areas. The front does
appear to lift north Wednesday night and into the area once
again. There is also a weak shortwave trough rotating in from
the southwest. Shower and thunderstorm chances will continue.
However, not seeing signals for heavy rainfall, with additional
QPF less than a half inch currently expected. Low temperatures
Wednesday night will be in the 50s.

&&

.LONG TERM /FRIDAY THROUGH MONDAY/...
Issued at 215 PM MDT Mon Jun 17 2024

West-southwesterly flow aloft continues on Friday before a shortwave
trough moves through during the evening-overnight hours, so we`ll
continue to carry around 30-40% PoPs in this timeframe as a sfc-850
mb low slides through the area. With eastward progression of the
upper trough, flow will veer to become west-northwesterly for the
weekend as a ridge builds over the western CONUS with high pressure
centered in vicinity of the Four Corners region. Daily weak
shortwaves moving through the flow will keep at least slight chance
to chance PoPs in the forecast, generally in the afternoon-evening
hours. Will need to continue to monitor the severe weather potential
as we near the weekend into the start of the work week as decent
shear and instability look to be available based on current model
guidance and moisture looks to be there with PWAT values
generally to around 1-1.5 inches through much of the period,
highest at the close of the work week-start of the weekend.
Another potential impact to monitor would be another bout of
breezy to windy conditions at the close of the work week as
south-southwesterly winds increase ahead of the approaching
system.

For temperatures, expecting highs in the middle 80s to low-mid 90s
over the weekend, warming further into the 90s to start the work
week. Low temperatures are forecast to be generally in the 60s.

&&

.AVIATION /18Z TAFS THROUGH 18Z TUESDAY/...
Issued at 1100 AM MDT Mon Jun 17 2024

KGLD...VFR conditions are currently forecast through the period.
Southerly winds gusting 30 to 45kts are expected from taf
issuance through much of tonight with the stronger gusts after
dark. Winds shift to the northwest around 12z, gusting up to
25kts. Winds then veer to the north, gusting up to 30kts.
Presently, no precipitation is forecast. Its possible that the
terminal could be impacted by thunderstorms in the 23z-02z
timeframe but confidence and areal coverage are too low to
presently include in the forecast. There could be sub VFR cigs
for a few hours either side of 12z Tuesday.

KMCK...VFR conditions are currently forecast through the period.
Southerly winds gusting 25 to 40kts are expected from taf
issuance through much of tonight with the stronger gusts after
sunset. Winds veer to the west-southwest, gusting up to 25kts
around 12z, shifting to the northwest by 15z with gusts up to
30kts. Presently, no precipitation is forecast. Its possible
that the terminal could be impacted by thunderstorms in the
01z-04z timeframe but confidence and areal coverage are too low
to presently include in the forecast. Sub VFR cigs are possible
for a few hours either side of 12z Tuesday.

&&

.GLD WATCHES/WARNINGS/ADVISORIES...
KS...High Wind Warning from 9 PM MDT /10 PM CDT/ this evening to 3
     AM MDT /4 AM CDT/ Tuesday for KSZ001-002-013-014.
CO...Red Flag Warning until 9 PM MDT this evening for COZ253-254.
NE...High Wind Warning from 9 PM MDT /10 PM CDT/ this evening to 3
     AM MDT /4 AM CDT/ Tuesday for NEZ079-080.

&&

$$

SHORT TERM...JN
LONG TERM...CC
AVIATION...99