727
FXUS63 KGLD 132210
AFDGLD

Area Forecast Discussion
National Weather Service Goodland KS
410 PM MDT Sat Jul 13 2024

.KEY MESSAGES...

- Landspout threat along the southern part of the forecast area
  this afternoon.

- Record to near record highs through Monday.

- Heat Index values up to 107 degrees possible through Monday
  afternoon.

- Increase in rain chances middle of next week along with a cool
  down.



.SHORT TERM /THROUGH MONDAY NIGHT/...
Issued at 249 PM MDT Sat Jul 13 2024

Latest upper air analysis shows the ridge centered over the Four
Corners Region.  Water vapor imagery shows dry air on the east half
of the ridge, with a plume a moisture on the west half.

For the rest of the afternoon a surface trough is expected to stall
over the southern and southeastern part of the forecast area.  As
the afternoon progresses an upper level short wave trough will
deepen over the trough, and the LLJ nose will form over it as well.
There is very little CAPE to work with given the very dry, hot air.
Any lift will be tied to the surface trough, so any storms that form
should fall apart as they move off the trough.  Am thinking the best
area for storms to form will be near Greeley County where the
surface trough intersects the dry line.  Main threat with these
storms will be wind gusts up to 60 MPH.

The surface trough, especially Greeley and Wichita counties, looks
favorable for a landspout to form. (This is where the dry line and
surface trough meet.) There is surface vorticity along the boundary
and mean wind is nearly parallel to the surface trough.
A landspout occurred yesterday in Washington County, CO along the
dry line, so am thinking the similar environment today should yield
a landspout threat. The window for the landspout threat will be 3 PM
MT to 6 PM MT. Once temperatures begin to cool the threat for
landspouts should end.

Tonight storm activity will end before mid evening.  The rather warm
lows will not provide much relief from the heat for the eastern half
of the forecast area.

Sunday the ridge moves slightly further over the forecast area. This
will cause temperatures to be warmer than today; near to or .
setting records.  During the afternoon the dry line should be near
the western edge of the forecast area.  During this time an upper
level short wave trough proceeds east.  As such there may some
isolated storms. Am thinking the dry line will also serve as a focus
for storm development.

Sunday night there may be some isolated storm activity over the
northwest part of the forecast area.  This activity will end mid
evening as temperatures cool and the upper level short wave trough
fills.  Lows will be even warmer than tonight, further exacerbating
the effects of the heat.

&&

.LONG TERM /TUESDAY THROUGH SATURDAY/...
Issued at 249 PM MDT Sat Jul 13 2024

Main focus for this period is the rainfall chances and the cool down
mid week.

Monday will be the final day for the hot weather prior to the cool
down.  The upper level ridge shifts slightly to the west and winds
will be from the north.  850mb temperatures are slightly cooler than
Sunday, so am thinking temperatures should be cooler.  Given the
continued hot weather that is similar to the weekend, decided to
extend the heat advisory to Monday for all counties except East
Central CO.  During the afternoon an upper level short wave trough
will approach from the west.  This may lead to isolated storms that
move into the forecast area Monday night and increase in coverage as
dew points increase and the upper level short wave trough interacts
with the low level jet.  A cold front will move through, which will
also aid in rain formation.

Tuesday night another round of rain activity will move through the
forecast area as another strong upper level short wave trough moves
through.  This looks to be a similar setup to the prior day.  The
GFS and ECMWF ensembles both have the best chances for rainfall for
Tuesday night.  Also noticed the probability is higher than
yesterday for precipitation.  A cold front may stall over the
forecast area due to a strong trough to the northeast and the strong
ridge to the southwest.  If this does happen, the front will serve
as a focus for repeated storm development.

Wednesday through Saturday the active weather pattern will continue
as upper level short wave troughs round the ridge and move over the
forecast area.  There was concern from the last shift regarding if
much water vapor would round the ridge, or if the northwest flow
would be dry.  There is currently water vapor rounding the northern
half of the ridge.  But will this continue to be the case by mid
next week?  Would think the ridge slightly expanding west over the
Pacific would aid in bringing more water vapor around the ridge not
less.  However the air is quite dry west of the ridge over the
Pacific, and the weather pattern does not change much between now
and the middle of next week.

High temperatures have cooled for Thursday onward compared to what
was seen yesterday.  This may be due to the trough not moving off as
quickly as was forecast yesterday.  Slower movement east seems
warranted given the unusually strong intensity of the trough for
this time of year.

&&

.AVIATION /00Z TAFS THROUGH 00Z MONDAY/...
Issued at 400 PM MDT Sat Jul 13 2024

KGLD...VFR conditions are expected through the period. A messy
wind forecast with speeds a few knots either side of 6kts so
cant quite go VRB06kts. Presently, an easterly component to the
wind at speeds under 10kts is forecast from taf issuance through
06z, veering to the south then southwest at similar speeds
through 10z. After 11z, west winds under 10kts flip back to
east-southeasterly at speeds possibly up to 12kts from late
morning through the afternoon. Confidence in the wind forecast
is below average at the moment.

KMCK...VFR conditions are expected through the period. A
generally light and variable wind at taf issuance will continue
through about 16z Sunday before establishing an east to
southeast component at speeds up to 10kts after 17z.

&&

.CLIMATE...
Issued at 202 PM MDT Fri Jul 12 2024

Saturday high temperature records
            Record  Year

Yuma        108     1954
Burlington  103     1934
Goodland    108     1934
Tribune     107     1934
Colby       111     1934
McCook      108     1954
Hill City   115     1934


Sunday high temperature records
            Record  Year

Yuma        105     2010
Burlington  105     1925
Goodland    107     1934
Tribune     107     1934
Colby       109     1934
McCook      109     1954
Hill City   113     1934


Monday high temperature records
            Record  Year

Yuma        102     2006
Burlington  103     2000
Goodland    106     1925
Tribune     108     2000
Colby       108     1925
McCook      112     1925
Hill City   113     1934

&&

.GLD WATCHES/WARNINGS/ADVISORIES...
KS...Heat Advisory until 9 PM MDT /10 PM CDT/ Sunday for KSZ001>004-
     013>016-027>029-041-042.
     Heat Advisory from 9 AM MDT /10 AM CDT/ to 8 PM MDT /9 PM CDT/
     Monday for KSZ001>004-013>016-027>029-041-042.
CO...Heat Advisory until 9 PM MDT Sunday for COZ090>092.
NE...Heat Advisory until 9 PM MDT /10 PM CDT/ Sunday for NEZ079>081.
     Heat Advisory from 9 AM MDT /10 AM CDT/ to 8 PM MDT /9 PM CDT/
     Monday for NEZ079>081.

&&

$$

SHORT TERM...KMK
LONG TERM...JTL
AVIATION...99