611
FXUS64 KLZK 292354
AFDLZK

Area Forecast Discussion
National Weather Service Little Rock AR
654 PM CDT Sat Jun 29 2024

...New AVIATION...

.SHORT TERM...
(This evening through Monday)
Issued at 138 PM CDT Sat Jun 29 2024

Early afternoon water vapor satellite imagery showed a broad
elongated ridge draped over the southeastern CONtinental United
States (CONUS) and a seasonably respectable upper level trough
pushing east, but north of the ridge axis, over the western upper
midwest. Regional surface observations showed temperatures in the
lower to mid 90s with dew point values in the mid to upper 70s,
bringing heat index values up into the 105 to 110 degree range
across much of Arkansas. Heat advisories and Excessive Heat
Warnings continue through this evening as very little relief from
the heat will occur overnight tonight. To the north, surface
observations shows a weak cold/cool front pushing south towards
central Missouri and east central Kansas.

Through Sunday morning, the Missouri frontal boundary is expected
to continue south and move into northern Arkansas by this evening.
In addition to short range model guidance advertising this timing,
the southern extent of the shortwave trough to our north appears
to be sufficient to allow this to actually happen. As the
admittedly weak frontal boundary moves into northern Arkansas and
encounters the heat and humidity, it should provide enough lift
and low-level convergence for some isolated to scattered rain
shower and thunderstorm activity to develop right around and just
after sunset. This activity will likely weaken overnight as the
boundary continues to move south towards central Arkansas. Once
the nocturnal boundary layer is established, weak low-level
convergence will likely not be able to continue to support rain
shower and thunderstorm activity developing farther south.

The boundary is expected to settle in around the Interstate 40
corridor before stalling out in the pre-dawn hours of the day on
Sunday. How far south the boundary sinks will likely depend on the
amount of rain shower and thunderstorm activity that develops this
evening as the boundary enters the state. Wherever the boundary
stalls out will mark where weather impacts are focused on Sunday.
To the south of the boundary, another day of excessive heat is
likely. To the north, it won`t be significantly cooler, but there
should be enough cloud cover in place to take the edge off of the
heat impacts by providing more shade than sun on average
throughout the day. Closer to the boundary, scattered showers and
thunderstorms are likely to develop by early afternoon and
possibly as early as late Sunday morning. We`re not looking at
anything significant in terms of a severe thunderstorm threat,
but collapsing thunderstorms producing microbursts and localized
wind damage are possible.

Showers and storms should diminish after sunset and the boundary
will continue to sink to the south and southwest with northeast
winds building in across Arkansas. The boundary is expected to
wash out to our south, but the northeast surface winds are
expected to continue into the day on Monday which will bring
significantly drier and somewhat cooler air across Arkansas. This
should allow temperatures across the state to top out in the upper
80s to lower 90s with dew point values falling into the mid 60s
which will keep heat index values around 90 degrees and provide
some much needed relief from today`s heat. Enjoy the day while it
lasts; the long term forecast brings the heat back across Arkansas
in full force after Monday.

Cavanaugh

&&

.LONG TERM...
(Monday Night through next Saturday)
Issued at 138 PM CDT Sat Jun 29 2024

A stout and expansive upper ridge will be situated over the
ArkLaTex`s region to begin the long term period. At the surface,
winds should be in the process of switching from an Erly direction
back to a Srly component. With this switch of winds back to a Srly
direction, temperature and moisture advection will resume across AR.
The pattern will change very little heading through mid-week with
the ridge drifting slightly Ewrd towards the TN Valley.

A few showers and isolated thunderstorms may approach Nrn AR on
Wednesday afternoon and again on Friday, better statewide coverage
possible for Friday, with the approach of a cold front. The cold
front will be aided by a passing upper short wave trough traversing
the Nrn Plains into the Nrn MS Valley regions.

Temperatures through the upcoming work week are expected to top out
in the mid 90s to near 100 degrees each day. Low temperatures are
expected to range from the 70s to around 80 degrees. Heat headlines
will likely be needed for portions of AR each day through the week.
Wednesday and Thursday appear to be the hottest day in regards to
high and low temperatures and afternoon heat index values. This
level of heat will be dangerous, and for those working outdoors or
outdoors in general, be sure to take plenty of breaks during the
hottest part of the day and stay well hydrated.

70

&&

.AVIATION...
(00Z TAFS)
Issued at 650 PM CDT Sat Jun 29 2024

VFR conds are expected to prevail thru most of the fcst PD.
However, ongoing convection acrs northeast OK and southwest MO is
fcst to eventually affect parts of north AR later this evening,
with MVFR conds noted at KHRO and KBPK. Convection is expected to
diminish in intensity/coverage later tngt as an assocd CDFNT drops
into the state. Sctd convection expected Sun acrs central and southern
AR as the sfc bndry drifts further to the south, with PROB30 groups
mentioned for these locations.

&&

.LZK WATCHES/WARNINGS/ADVISORIES...
Heat Advisory until 8 PM CDT this evening for ARZ004-005-014-024-
103-112-113-123-203-212-213-221>223-313.

Excessive Heat Warning until 8 PM CDT this evening for
ARZ006>008-015>017-025-031>034-039-042>047-052>057-062>069-121-
122-130-137-138-140-141-230-237-238-240-241-340-341.

Heat Advisory from 10 AM to 8 PM CDT Sunday for ARZ042>047-
052>057-062>069.

&&

$$

SHORT TERM...66
LONG TERM....70
AVIATION...44