Area Forecast Discussion Issued by NWS Goodland, KS
000
FXUS63 KGLD 290350
AFDGLD
Area Forecast Discussion
National Weather Service Goodland KS
950 PM MDT Sun May 28 2023
.UPDATE...
Issued at 903 PM MDT Sun May 28 2023
Latest data continues to hint at elevated strong to severe
thunderstorms forming over the central part of the forecast area
between 10 PM and 2 AM MDT. Model soundings suggest there will be
enough moisture advection to provide CAPE values of 1000-1300
j/kg. The LLJ nose moves over the central part of the forecast
area, which will serve as a focus for storms to form on. Am
doubtful there will be much of a severe wind threat with these
storms. It should be more of a hail threat and possibly a tornado
threat given the presence of a boundary nearby with slow storm
motion and very little ML CINH. The storms will end after a few
hours or less as the drier air accompanying the upper level ridge
axis moves in from the west.
UPDATE Issued at 817 PM MDT Sun May 28 2023
Scattered storms are forming along and behind the boundary. The
LLJ nose is accompanying the boundary northward, thus aiding in
storm development. There is some elevated CAPE to work with.
However this won`t last too long before the environment becomes
too stable and drier air moves in. Further west am thinking the
storm activity coming in from the west shouldn`t last too long
either due to the environment drying out. Therefore am expecting
the storm activity to end/slide eastward out of the forecast area
around midnight if not before.
&&
.SHORT TERM...(This evening through Wednesday night)
Issued at 155 PM MDT Sun May 28 2023
Across the Tri State region this afternoon, skies continue to vary
widely from sunny in some areas down to cloudy skies, but the trend
for the past couple hours is a slow clearing one. The cloud cover
has held temps in check through the early afternoon with a range
from the mid 60s to the mid 70s. Warmest areas currently with most
sunshine. The airmass continues to remain moist with dewpts in the
mid 50s to lower 60s. Most locales have seen winds been fairly light
from the east-southeast.
For the remainder of the afternoon hours on into the evening, the
main weather concerns again will be on the formation of scattered
thunderstorms and their potential for heavy rainfall. Also for
today/tonight, with a Marginal Risk for severe wx in place,
wind/hail threats are also possible.
Currently the cwa will be looking at a couple areas where storms
could develop and move into the area. First, there is a surface low
south of the cwa with a trough extending eastward southern portions
of the area. Storms are firing up south of this trough, which the
NAM/HRRR seem to have a decent handle on this. This guidance does
bring some of this activity northeast impacting eastern locales
through this evening.
The other spot will be coming from north central Colorado as a
shortwave swings southeast through the area. There are isolated
storms already cropping up.
Overall, with SPC having the area under a Marginal Risk for severe,
we will be looking for hail/wind threats as well as locally heavy
rainfall. Storms will be slow moving as with the past few days, so
possible training of storms could occur. Areas north of Highway 36
will be most prone due to high soil moisture from current/recent
rainfall. Also, with the boundary over the region, land spouts are
possible from Greeley to Graham counties.
For Monday through Wednesday, models carry and upper ridge through
the central/southern Plains during this time. Several shortwaves
traverse the northern periphery of the ridge each afternoon/evening,
bringing a chance for isolated/scattered storms. With high PWATs
each day, still keeping locally heavy rainfall as main threat, but
hail/wind can`t be ruled out.
For temps, highs temperatures expected from Monday into the midweek
timeframe will range mainly in the 80s, but some locales could be
limited due to afternoon clouds/precipitation. Lows during the
extended will range mainly in the 50s with warmest areas east of
Highway 25.
.LONG TERM...(Thursday through Sunday)
Issued at 1258 PM MDT Sun May 28 2023
Another active pattern is expected starting midweek and continuing
through next weekend.
The long term period will be driven by a negatively tilted trough
that will attempt to move in from the Great Basin region while a
ridge over the Tri-State area will move north and possibly become a
cutoff high pressure system. This set up, which will be slow moving,
will generally create an upper level flow pattern from the south for
the end of the workweek and a southeasterly pattern over the
weekend. As these two features conflict over the Great Plains,
multiple shortwaves will form and cause times and areas of increased
disturbance for the Tri-State area.
Moisture will continue to be plentiful with PWATs generally staying
around the 0.9 - 1.2 inch range. Locations in northwest Kansas could
see PWATs as high as 1.5 inches. Instability will not be in short
supply as southerly winds will keep the region near seasonally
average temperatures, around 80 degrees. The limiting factor will
once again be the lack of shear. EBWD values for period max out
around 25 kts, with values Thursday evening hovering around 10-15
kts. For the storms that do form, and there likely will be a decent
amount of them, they will likely be efficient, heavy rain producing
storms moving at a fairly slow pace, likely less than 20 kts. All
hazards are possible for the storms later this week and over the
weekend, with a focus on flooding.
High temperatures are expected to slowly cool from Thursday onwards
as the LLJ will not be very strong. Low temperatures will stay
pretty stable as the extra moisture will allow us to retain heat
better.
&&
.AVIATION...(For the 06Z TAFS through 06Z Monday night)
Issued at 947 PM MDT Sun May 28 2023
VFR conditions forecast for the TAFs. The main impact will be the
potential for strong to severe thunderstorms developing near KGLD
by 6z (if not sooner). Storms will be moving slowly, so heavy
rainfall will be the main threat. At this time, am not very
confident in visibility falling below VFR due to heavy rainfall,
but it could happen if storms move over the site.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
UPDATE...JTL
SHORT TERM...JN
LONG TERM...CA
AVIATION...JTL