071
FXUS63 KDDC 142320
AFDDDC

Area Forecast Discussion
National Weather Service Dodge City KS
620 PM CDT Sun Jul 14 2024

.KEY MESSAGES...

- Intense afternoon heat will continue Sunday and Monday.

- Scattered showers and thunderstorms are expected Tuesday
  night. Locally heavy rainfall and marginally severe storms are
  possible.

- Much milder, more comfortable temperatures are expected
  Wednesday.

&&

.DISCUSSION...
Issued at 200 PM CDT Sun Jul 14 2024

Midday infrared satellite imagery showed only a few clouds
drifting over SW KS, with strong subsidence on the eastern
periphery of a strong 598+ dm midlevel ridge centered near the
Four Corners. Surface analysis showed a distinct boundary and
accompanying wind shift bisecting SW KS, with light northeast
winds north and west of DDC. Models allow this boundary to wash
out through peak heating, but the lack of downslope will likely
keep temperatures several degrees "less hot" than forecast for
this afternoon.

Clear and quiet tonight, under strong high pressure aloft, with
scattered cirrus increasing toward sunrise Monday. Light S/SW
winds will prevail, with all locations holding in the lower 70s
through sunrise.

Monday may very well end up being the hottest day of the summer.
Models depict SWly downslope compression, enhancing already
super hot 850 mb temperatures as high as 35C. 12z GEFS ensemble
members show near 100% probability of 2m surface temperatures
over 100 across all zones, and NBM is plenty hot, with afternoon
temperatures of 104-108. If it wasn`t for all of the recent
rainfall and resultant vegetation/evapotranspiration, many
locations would reach 109-110 Monday afternoon. Still, even with
the greenery, some locations will approach record heat levels.
The record high at DDC for July 15 is 109 (2022), and the
forecast will carry of a high of 106. This will be a relatively
dry heat with dewpoints in the 50s; as such, heat indices will
be held less than 105 about west of US 283, and 105-110 eastern
zones. For simplicity, just kept the inherited heat advisory
going all zones through Monday afternoon. Temperatures this hot
are dangerous regardless of specific heat index criteria.

The heat will finally relax Tuesday, as winds trend NEly behind
an initial cold front. Still hot, but the 100-105 will be
replaced with 90s. With the added easterly boundary layer
component, a noticeable increase in humidity is expected, with
dewpoints will into the 60s. So although "cooler", it may
actually feel more uncomfortable for more people. A weak
shortwave will dent the eastern periphery of the ridge some more
Tuesday night, maintaining moisture influx on northeast/east
winds. Guidance has been consistent on scattered showers and
thunderstorms during the Tuesday night time frame, with
potential MCS development most likely from NE Colorado to
central Kansas. NBM pops are in the chance to likely category
Tuesday night, favoring the northern zones, and these were
accepted. 12z GEFS ensemble members already suggest a 70%
probability of QPF > 0.10 inch across much of SW KS Tuesday
night, and locally heavy rainfall is probable. Up to 1 inch of
rain is a distinct possibility especially given an organized
MCS. Marginally severe outflow winds may become a risk from any
organized linear convective system, per SPC Day 3 marginal
probability.

Heat relief will become much more obvious Wednesday, as
outflow and cool advection on northeast winds are enhanced by
any departing MCS. With 850 mb temperatures reduced to near
20C, afternoon temperatures will be pleasantly reduced to the
lower to mid 80s.

Thursday through Saturday, 12z global models and their ensembles
are in excellent agreement that the heat will not be allowed to
return to SW KS through the remainder of the week. During this
period, a meridional amplified flow is forecast across North
America, with the hot upper ridge finding a home over the Great
Basin, well west of SW KS. The resulting N/NWly flow aloft will
ensure afternoon temperatures remain pleasant, in the 80s, as
shown by the latest iteration of the NBM, and 12z MEX guidance.

&&

.AVIATION /00Z TAFS THROUGH 00Z MONDAY/...
Issued at 610 PM CDT Sun Jul 14 2024

Mid level cloud cover, scattered to broken deck of clouds at or
above 12000ft AGL, will be on the increase overnight as a weak
upper level trough crosses the West Central High Plains. This
may result in an area of weakening/dissipating thunderstorms
moving into west central Kansas towards 06z. Although the chance
for storms surviving as far east as Garden City or Hays is very
low (<10%) a period of gusty north winds may occur between 06z
and 09z Monday at these two TAF sites (Garden City and Hays).
Outside this brief wind shift around 06z...the prevailing winds
overnight will be southerly at 10 knots or less. Between 12z
and 18z Monday the southerly winds shift to the west southwest
and increasing to around 15 knots as a surface boundary crosses
southwest Kansas early in the day.


&&

.DDC WATCHES/WARNINGS/ADVISORIES...
Heat Advisory until 7 PM CDT /6 PM MDT/ Monday for KSZ030-031-
043>046-061>066-074>081-084>090.

&&

$$

DISCUSSION...Turner
AVIATION...Burgert