900
FXUS63 KGLD 262322
AFDGLD

Area Forecast Discussion
National Weather Service Goodland KS
522 PM MDT Fri Jul 26 2024

.KEY MESSAGES...

- A prolonged heat wave will affect northwest Kansas and
  southwest Nebraska next week, beginning on Sunday. High
  temperatures are likely to reach or exceed 100 degrees each
  day. Temperatures and heat indices approaching 105 to 110
  degrees are expected on Tuesday and Wednesday.

- An isolated shower or thunderstorm could impact northeast
  Colorado this evening.

- 20% to 30% chance for thunderstorms Saturday evening, mainly
  in eastern Colorado and adjacent Kansas-Nebraska border areas.

&&

.UPDATE...
Issued at 220 PM MDT Fri Jul 26 2024

Quick update to the going forecast for this evening to add in a
15-20% chance for an isolated shower or storm to clip western
portions of Kit Carson, Yuma and Cheyenne counties. Regional
radar showing some convection getting going near the I-25
corridor with a slow movement east to our colorado counties
this evening. Current CAMs (HRRR/NamNest) show most of the
activity dissipating before entering the western CWA, but some
residual rw/trw could drift into the area later.

&&

.SHORT TERM /THROUGH SUNDAY NIGHT/...
Issued at 1215 PM MDT Fri Jul 26 2024

Overview: An upper level ridge presently extending NE from the
Desert Southwest to the Northern Plains will weaken and erode
today into Saturday as troughing /cyclonic flow/ aloft..
extending southward from a vertically stacked low in western
Canada (Alberta-Saskatchewan).. envelopes the northern and
central Rockies. Re-amplification of the aforementioned ridge
(over the Desert Southwest and Southern-Central Plains) will
follow, Sun-Sun night.

Today-Tonight: Expect sensible weather conditions similar to
yesterday, albeit noticeably breezier.. in response to a
tightening MSLP-850mb height gradient /strengthening low-level
southerly flow/ on the eastern periphery of a developing lee
trough in Colorado.. and effective downward momentum transport
associated with strong insolation and robust vertical mixing. A
41 mph southerly wind gust was measured at NWS Goodland (KGLD)
at 11:39 am MDT / 1739 UTC.

Sat-Sat night: A short-lived pattern transition is expected in
this period as the southern fringe of the mid-latitude
westerlies further erode.. and briefly supplant.. the
aforementioned ridge over the region. Such a flow regime is
relatively more supportive of [1] daily/diurnal lee cyclone
development and [2] scattered convective development (mainly in
climatologically/topographically favored locations). Expect
temperatures similar to today.. along with a potential for
scattered late afternoon and evening convection, mainly in
eastern Colorado and adjacent KS border areas. Confidence
remains below average with regard to convective development,
coverage and eastern extent.

Sun-Sun night: Guidance suggests that re-amplification of the
central CONUS ridge, associated height rises and northward
regression of the mid-latitude westerlies will commence on
Sunday. Expect dry conditions and warmer temperatures with highs
reaching or exceeding 100F across the majority of the area.

&&

.LONG TERM /MONDAY THROUGH FRIDAY/...
Issued at 103 PM MDT Fri Jul 26 2024

The latest runs of the GFS and ECMWF continue to show a persistent
zonal flow aloft at least Monday through Wednesday, before re-
amplification of 500 ridge into the Rockies. The result will be a
shift to northwest flow aloft.

850 mb temps for the Mon-Wed timeframe are expected to peak in the
+30c to +36c range. This will result in above normal hot and very
dry conditions area-wide through downslope warming. At the surface
there is a weak trough meandering through the CWA, settling south of
the area on Thursday/Friday. This boundary will interact with a weak
shortwave moving over the area on the eastern side of the upper
ridge. Increased low level moisture and upslope flow on SE winds
will allow for the western CWA to see 15-20% chance for rw/trw.

Model soundings next Friday have inverted-v profiles to around
600mb, suggesting wind should be the main threat should any storms
do form as lower levels will be very dry. PW values now at least an
inch could bring about a brief local downpour. If any hail does
occur it should be at the onset as the drier air should melt down
any potential large stones.

Along with the above normal heat expected, the other concerns for
the Tri State region will be fire weather danger. The persistent day-
by-day drying of the region with lack of any appreciable moisture
through at least midweek, will bring about RH readings Monday-
Wednesday mainly in the lower to mid teens. The main areas seeing
this will be along/west of Highway 25. East of this, locales will
only reach into the upper teens to mid 20s for readings. While RH
will be hitting criteria for many through midweek, winds will not
be. There still will be elevated to near critical concerns despite
this due to the persistent drying effects over a 72 hour period
making fuels much easier to start/burn.

For temps, above normal, hot daytimes highs are expected area-wide
for the upcoming week. On Monday, the area will see a range from the
upper 90s into the lower 100s. For Tuesday, lower to mid 100s
expected. Some locales east of Highway 25 could see upper 100s.
Going into Wednesday, another round of lower to mid 100s. Going into
Thursday and Friday, mainly mid to upper 90s w/ some spots Thursday
afternoon around 100F.

With these hot temperatures, heat indices are also expected to make
an impact across the CWA. The latest guidance has brought in
slightly drier air, but readings could still approach 105-100F,
especially east of Highway 25. Areas east during the overnight may
also have high readings as well.

Each afternoon, the hottest areas will be in locales along/east of
Highway 25. With these hot temperatures, near record/record readings
are possible. Please refer to the Climate section below for further
information.

Overnight lows most nights will range in the 60s. A few nights will
have areas along/east of Highway 25 around 70F, even into the lower
70s.

&&

.AVIATION /00Z TAFS THROUGH 00Z SATURDAY/...
Issued at 514 PM MDT Fri Jul 26 2024

VFR conditions are expected to prevail through the period, as
will south-southeasterly winds. 0-9Z, wind gusts are expected
to slowly weaken, eventually slowing to under 20 kts, before
picking back up after sunrise. The smokey haze near KMCK is
expected to continue lifting, although it`s being a lot slower
than originally forecast. By 6Z, guidance is showing 6+ SM
visibility, until then, it looks to hover around 6SM. Through
around 6Z, some showers and storms will be decaying in eastern
Colorado, which could produce an outflow boundary that would
impact KGLD. Impacts would just be a brief spell of variable
and gusty winds.

&&

.CLIMATE...
Issued at 115 AM MDT Fri Jul 26 2024

July 29 High Temperature Records (F):

Goodland......104 in 1947
McCook........109 in 1947
Burlington....100 in 2012
Hill City.....108 in 1917

July 30 High Temperature Records (F):

Goodland......106 in 1935
McCook........105 in 2002
Burlington....101 in 2012
Hill City.....109 in 1976

July 31 High Temperature Records (F):

Goodland......105 in 2002
McCook........107 in 2002
Burlington....102 in 2002
Hill City.....113 in 1934

Goodland has the potential for 5 consecutive days of highs of
100+ degrees which would tie it for the 14th longest on record.
Last time this happened was July of 2012.

McCook is also currently forecasted at 5 consecutive days of
100+ degree temperatures which would tie it for 20th all time.
However a few days of overachieving temperatures could put them
in the top 6 all time.

&&

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

&&

$$

UPDATE...JN
SHORT TERM...BV
LONG TERM...JN
AVIATION...CA
CLIMATE...