394
FXUS64 KAMA 080018 AAA
AFDAMA

Area Forecast Discussion...UPDATED
National Weather Service Amarillo TX
718 PM CDT Sun Jul 7 2024

...New UPDATE, AVIATION...

.UPDATE...
Issued at 659 PM CDT Sun Jul 7 2024

First round of storms this aftn has focused more along the outflow
boundary south of the area rather than the frontal boundary that
was pushing through the Panhandles.This suggest we will have to
wait for the next upper S/WV and H7 frontal boundary to generate
storms after midnight. Given this have lowed POPs across the
board for the evening period but did maintain a low POP in the SE
in case any outflow pushed back north from SCT TSTMs to the south.
It still looks favorable for the overnight storms to pan out
especially in the western and southern zones and POPs remain
60-90% after midnight. Given a south shift by most CAMs/HREF of
highest QPF and fact that we missed out on the first round, we
have removed Beaver and Ochiltree from the Flood Watch and might
need to consider removing more of the north later this evening.
HREF continues to show 20-50% chance of 1" or greater rainfall
across the southern Panhandles. 2 inch or greater probs are 10-20%
per the HREF for areas along and especially south of I-40.

&&

.SHORT TERM ...
(This evening through Monday night)
Issued at 141 PM CDT Sun Jul 7 2024

It is July in the Texas and Oklahoma Panhandle. So you know what
that means: boundaries, boundaries, and more boundaries! In this
case, as of the latest 18Z obs, we have a cold front moving
south-southwest into the northeast combined Panhandles. We also
have an outflow boundary from convection in south central
Oklahoma moving west-northwest into towards the SE TX Panhandle,
and we then have a third, and more subtle sfc boundary across the
western TX Panhandle, leftover from thunderstorms earlier this
morning. Through this afternoon and towards midnight tonight,
these aforementioned boundaries may cause strong to severe
thunderstorms to develop. Latest hi-res CAM`s and short range 12Z
model data are not quite in an accord of output. LL shear sub 6 km
is quite anemic in the latest HRRR/RAP analysis through 00Z
tonight across the board. As a result, lift from the series of
boundaries in the area will have to help storms reach convection
initiation as overall buoyancy alone will not suffice. Best low
level moisture content is in the SE TX Panhandle, along with best
diurnal heating and no antecedent rainfall from earlier this
morning, the highest probability of severe storms should be in
this area before midnight tonight. Cannot rule out areas along and
ahead of the front as it moves south, or the subtle sfc boundary
in the western TX Panhandle, but the highest chances of a severe
thunderstorms before midnight is in the southeast Texas Panhandle.
Pronounced H850-700 theta-e advection, coupled with effective
shear >= 40 kts, along with MLCAPE/SBCAPE of 1000-2000 J/kg will
support severe thunderstorms, especially in the southeastern
Texas Panhandle. If cold front and westward moving boundary from
central Oklahoma collide in the eastern TX Panhandle vicinity,
this could definitely aid in thunderstorm development further with
areas of lift aiding the environment for lift. Large hail and
damaging winds will be the main threats for severe weather, along
with the possibility of flooding, especially in the eastern
Panhandles with slow moving thunderstorms, as well as PWAt values
near 1.5" in some locations. Plenty of low level moisture in the
atmosphere.

Looking past midnight tonight, latest model and numerical data
shows a more organized line of convection developing along the
front range of the Rockies which may provide our best rain chances
for the Panhandles within the first 24 hours of this forecast.
This would support a secondary area of severe thunderstorms
favoring the central and western Panhandles for a severe
thunderstorm threat of damaging winds and localized flooding. A
perturbation across the central Rockies with upslope flow will
congeal discrete cells on the front range into a line of storms
moving southeast in the combined Panhandle during the overnight
hours tonight. Probabilities of severe criteria storms reaching
the I-40 corridor is lower than further north near the source of
the original storms, along with steering flow being a bit stronger
closer to the mountains. But cannot rule out a severe storm
anywhere in the Panhandles from midnight tonight through sunrise
tomorrow morning. Residual outflow boundaries will move south and
further push the main cold front south as well. So going
throughout the day tomorrow, rain chances should decrease from
north to south.

Another quite cool topic to talk about is how nice the
temperatures will be behind the passing cold front for tomorrow.
High temperatures tomorrow will be in the mid to upper 70s for
most areas, a nice change of pace for July. Low temperatures
tomorrow night will range in the 50s across the area. Looking at
DESI probs, there even is around a 10% chance that portions of the
western combined Panhandles may see low temperatures in the upper
40s. Quite refreshing from our normal July heat in the Panhandles.

Meccariello

&&

.LONG TERM ...
(Tuesday through next Saturday)
Issued at 141 PM CDT Sun Jul 7 2024

Mid to long range models indicate that the upper level pattern
will change near the start of the extended period. The 500 mb
trough should de-amplify and transition towards the northeast
CONUS. Meanwhile, upper level ridging overspreads from the west
and high pressure builds over much of the CONUS. Here on the High
Plains, monsoonal moisture will taper off as our upper level flow
turns from northwesterly to northerly.

A steady increase with heights aloft will also result in a steady
increase in surface temperatures through next week. Southerly
surface winds will take over across the CWA, aiding in warm air
advection. Tuesday should see highs in the 80`s and they will
rise into the 90`s for the rest of the week. A few isolated
hot spots may even reach 100 degrees this week like the Canadian
River Valley and Palo Duro Canyon. Chances for thunderstorms
should also greatly decrease. Initially, for Tuesday and
Wednesday, better thunderstorms probs are restricted to the far
western Panhandle. Afterwards, isolated afternoon convection
cannot be ruled out in certain portions of the CWA as the week
progresses, but the confidence this far out in time is extremely
low to add mentionable PoPs and the coverage is expected to be
quite limited.

Rangel

&&

.AVIATION...
(00Z TAFS)
Issued at 659 PM CDT Sun Jul 7 2024

Overnight thunderstorms are the main concern for this TAF cycle.
Best chances for storms in the Panhandles will be after 6 UTC and
continuing into Monday morning as a SE moving disturbance
interacts with frontal boundary and moisture over the area. The
best chance for impacts will be at AMA and DHT as the majority of
the activity moves south of GUY. MVFR conditions are expected
across the SW half of the Panhandles given combination of a
shallow front pushing through the area and greater coverage of
storms. VFR conditions are expected by around 18UTC Monday.

&&

.PRELIMINARY POINT TEMPS/POPS...
Amarillo TX                62  77  57  85 /  80  60  20  10
Beaver OK                  61  79  55  86 /  60  20   0   0
Boise City OK              57  77  53  85 /  70  30   0  10
Borger TX                  64  82  58  91 /  80  50  10   0
Boys Ranch TX              62  79  55  88 /  80  60  10  10
Canyon TX                  61  75  56  84 /  70  70  20  10
Clarendon TX               62  76  59  85 /  80  70  20  10
Dalhart TX                 59  78  52  87 /  70  40  10  10
Guymon OK                  59  79  53  87 /  70  20  10   0
Hereford TX                62  77  57  87 /  60  70  20  10
Lipscomb TX                62  79  56  86 /  80  40  10   0
Pampa TX                   61  77  57  85 /  80  50  10   0
Shamrock TX                63  79  60  87 /  90  70  20  10
Wellington TX              64  80  59  89 /  70  70  20  10

&&

.AMA WATCHES/WARNINGS/ADVISORIES...
TX...Flood Watch through Monday afternoon for TXZ005-009-010-014-015-
     019-020.

OK...None.
&&

$$

SHORT TERM...88
LONG TERM....55
AVIATION...88