-- Discussion containing changed information from previous version are highlighted. --
448
FXUS64 KAMA 261733 AAB
AFDAMA

Area Forecast Discussion...UPDATED
National Weather Service Amarillo TX
1233 PM CDT Wed Jun 26 2024

...New AVIATION...

.SHORT TERM ...
(Today through Tonight)
Issued at 420 AM CDT Wed Jun 26 2024

The center of the upper level ridge remains fixed in the desert
southwest CONUS for today. A northwest flow regime shall continue
to allow boundaries to exit off the lee side of the Rocky
Mountains and create additional thunderstorm chances for the
Panhandles this evening. All the while, high temperatures at the
surface prolong in the low to mid 100`s.

With regards to today`s heat, short term guidance suggest 850mb
temperatures generally exceed 33 degrees Celsius during the peak
heating hours of the today. This will allow for temperatures at
the surface to easily surpass 100 degrees Fahrenheit and in some
areas even 105 degrees. A Heat Advisory is currently in effect
for those areas that should see temperatures and heat index values
exceed 105 degrees. This is mainly for the Palo Duro Canyon and
the southeastern Texas Panhandle. Cloud coverage should not hinder
the surface from heating up through the day. Only by the late
afternoon hours will clouds have any affect on day time
temperatures, as thunderstorms are not expected before then.

Sufficient instability and moisture will be present once again
to allow thunderstorms to form in the afternoon hours today. Weak
forcing from perturbations entering off the high terrain in our
northwest zones will allow for scattered thunderstorm development,
mainly focused for the western half of our CWA. Depending on how
high our CAPE values can become, some storms may become severe
with damaging winds as the primary threat. 0-6 km bulk shear
between 30-40 kts will create good sustain for any robust storm,
the main question is how many, if any, can get there. CAMs and
other short range models give a bit of variety when producing
maximum suggested MUCAPE values for today, typically ranging from
500-3,000 J/kg. Though most guidance agrees that the highest
values will likely be placed in the Oklahoma Panhandle and the
northern Texas Panhandle. Overall, destabilization will be
adequate at least for general thunderstorms with some becoming
strong to severe. Once thunderstorms begin in the afternoon,
additional convective activity should extend into the night time
hours. Outflow and cold pools from prior thunderstorms will spark
new generation and keep the event ongoing perhaps even beyond
midnight and into early Thursday morning.

Rangel

&&

.LONG TERM...
(Thursday through Tuesday)
Issued at 420 AM CDT Wed Jun 26 2024

For Thursday and Thursday night, the upper level ridge of high
pressure is forecast to temporarily flatten somewhat and be
depressed southward. This will result in the upper level flow
becoming more semi-zonal or westerly. This would steer any showers
and thunderstorms that develop more eastward across the Oklahoma
Panhandle and far northern Texas Panhandle if the latest short
range models verify. Pops were fashioned in that manner in the
grids. Much like the past couple days, a few storms that develop
will have the potential to become strong to severe, with damaging
winds and large hail the primary hazards. High temperatures or
Heat Index values may once again approach or exceed 105 degrees
across the Palo Duro Canyon State Park and perhaps the far
southeastern counties such as Collingsworth. Another Heat Advisory
may be needed for that area for Thursday afternoon into early
evening.

Otherwise, little change was made to the long term periods Friday
through Tuesday. The upper level ridge of high pressure will continue
to be the overall dominant feature in our weather pattern through
Tuesday and beyond. A weak cold front may move across the region
late Friday night into Saturday and could temporarily bring slightly
cooler temperatures for this weekend before increasing again early
next week. Given the strength of this ridge, high temperatures
across many locations will likely approach or exceed 100 degrees
on Friday, Monday, and Tuesday. Heat Index values may approach or
exceed 105 degrees at times on one or more of the aforementioned
days, and additional Heat Advisories may be needed. As has been
the case the past several days, precipitation chances from Friday
through Sunday evening will strongly depend on the strength of the
upper level high pressure, its axis location and resultant steering
flow for storms, and how long our forecast area sits beneath it.
Nearly all medium range models continue to suggest periodic meandering
of the ridge axis from west to east during the extended periods.
The latest NBM pops and temperatures reflect the overall synoptic
pattern and were accepted with no major adjustments necessary for
this package.

02

&&

.AVIATION...
-- Changed Discussion --
(18Z TAFS)
Issued at 1226 PM CDT Wed Jun 26 2024

Thunderstorms are possible at the DHT and GUY TAF sites this
evening with some storms possible at the AMA TAF site after
midnight. Some of the storms may become severe with damaging winds
the main threat. Easterly winds this afternoon will turn more to
the south and southwest by Thursday morning. Winds will start get
gusty at DHT and GUY after about 14Z. Conditions are expected to
remain VFR outside of thunderstorms.
-- End Changed Discussion --

&&

.PRELIMINARY POINT TEMPS/POPS...
-- Changed Discussion --
Amarillo TX                73  99  76 102 /  30  10  10   0
Beaver OK                  70 100  76 102 /  20  10  20  10
Boise City OK              67  96  69  98 /  40  30  20  10
Borger TX                  75 105  80 107 /  30  10  10   0
Boys Ranch TX              72 100  75 104 /  40  10  10   0
Canyon TX                  72  99  75 101 /  30   0  10   0
Clarendon TX               73 100  77 101 /  20   0   0   0
Dalhart TX                 68  98  71 101 /  40  10  10  10
Guymon OK                  70  99  73 102 /  30  10  20  10
Hereford TX                72  99  74 103 /  30  10  10   0
Lipscomb TX                73 101  79 104 /  20  10  20   0
Pampa TX                   72  99  78 103 /  20   0  10   0
Shamrock TX                73 102  78 104 /  20   0   0   0
Wellington TX              74 103  79 104 /  20   0   0   0
-- End Changed Discussion --

&&

.AMA WATCHES/WARNINGS/ADVISORIES...
-- Changed Discussion --
TX...Heat Advisory until 8 PM CDT this evening for TXZ010-015-018>020-
     317.

OK...None.
-- End Changed Discussion --
&&

$$

SHORT TERM...55
LONG TERM....02
AVIATION...15