405
FXUS64 KAMA 131700
AFDAMA

Area Forecast Discussion
National Weather Service Amarillo TX
1200 PM CDT Mon May 13 2024

...New AVIATION...

.SHORT TERM ...
(Today through Tuesday night)
Issued at 324 AM CDT Mon May 13 2024

After several storms to round out the weekend, the main low
pressure that caused it will slowly be moving northeast through
Kansas today. On the backside of the departing mid level low
pressure system, we could see some additional showers or a storm
or two for the northeastern combined Panhandles, in closer
proximity to the departing low. Otherwise, a nice day in store
across the Panhandles. A bit breezy up north in closer proximity
to aforementioned departing low pressure system with steep sfc
gradient. But temperatures will be near average for mid May with
high temperatures ranging from the mid 70s to lower 80s.

A H500 ridge will move towards the southern Plains tomorrow. This
should keep most of the area dry once again. A secondary
disturbance poleward of the main ridge axis will develop some
showers and storms as it works across the central Rockies. This
could bring rain chances back to the northern combined Panhandles
tomorrow evening into tomorrow night as the main ridge axis moves
east. Chances are not too high (20-30%), but there is at least a
chance to bring more rain chances to the northern Panhandles where
rainfall is definitely needed. High temperatures tomorrow will
add another 10-15 degrees compared to today as southerly winds
return. Highs will range from the mid 80s to lower 90s.

Meccariello

&&

.LONG TERM ...
(Wednesday through Sunday)
Issued at 324 AM CDT Mon May 13 2024

Wednesday morning, an upper-level ridge will be just east of the
Panhandles with an upper-level trough over southern
California/northern Baja California, and a shortwave trough embedded
in the flow is currently expected to be somewhere in New Mexico.
Throughout the day the shortwave trough is favored to move toward
the Panhandles with dew points generally in the 40s and 50s in
place, though there are hints that an area of westerly or
southwesterly winds will move in to the southwestern TX Panhandle
allowing for some lower dew points to work in. Nonetheless, it
appears as though forcing in the form of PVA and a cold front moving
in from the north will arrive in the afternoon hours and allow for
the development of thunderstorms. Adding to the confidence for the
sustainability of thunderstorms is that all models suggest that
there will be rather impressive mid-level theta-e advection in the
afternoon. There is some question regarding how potential moisture
return will be, but given how models have handled it in the past few
weeks and the recent widespread rainfall, will opt to lean toward
the more potent moisture solutions (e.g., NAM). Steep to very steep
lapse rates will be in place from the surface through 6 km on the
order of an average of around 8.5 C/km to 9 C/km, thus it won`t take
much low-level moisture to get enough instability for the threat for
a strong to severe thunderstorm. The guidance that has greater low-
level moisture gives portions of the northern and eastern Panhandles
around 1000-1500 J/kg of MLCAPE. The strength of the low-level winds
won`t be anything to write home about, but deep layer shear looks
favorable for storm organization, thus supercellular structures will
be possible. A long, straight hodograph is favored which suggests a
splitting supercell will also be possible. The primary threats are
large hail (via steep lapse rates) and damaging winds (via steep low-
level lapse rates, inverted-V signature). Showers may continue
through Wednesday night as a cold front with low-level moisture
behind it moves through the Panhandles and additional lobes of
vorticity stream across the area.

Will have to watch Thursday as showers and thunderstorms may once
again occur. GFS progresses the upper-level trough quicker than the
ECMWF, and a surface low develops in western Texas. ECMWF is slower
with the trough progression and develops a surface low in
southwestern Texas. Additionally, GFS doesn`t push the cold front as
far south as the ECMWF. As noted above, low-level moisture is
wrapped in behind the cold front, thus for a more widespread threat
for showers and thunderstorms on Thursday, will need a solution like
the GFS to verify such that sufficient low-level moisture will be in
place across the Panhandles. A solution like GFS would also suggest
a few strong to severe thunderstorms would be possible for much of
the Panhandles. If a solution like the ECMWF verifies where the cold
front and moisture is further south, then perhaps only the southern
TX Panhandle could see a chance for showers and thunderstorms.

Owing to the timing differences between the models regarding the
progression of the trough, there`s quite a bit of uncertainty for
Friday. GFS could have lingering rain in the south, while ECMWF
would be dry.

An upper-level ridge builds over the Plains this weekend as an upper-
level trough moves in to the Western US. Sunday looks to be the
hottest day of the year thus far with widespread upper-80s to mid-90
degree highs. Will have to watch the early to middle portion of next
week for a potential weather system as the aforementioned upper-
level trough moves east. This could mean severe weather or dry and
breezy weather... or both. We`ll have to wait and see.

Vanden Bosch

&&

.AVIATION...
(18Z TAFS)
Issued at 1103 AM CDT Mon May 13 2024

VFR conditions at all terminals and across much of the panhandles
for today and overnight into Monday. Currently the threat of any
rain shower much less thunderstorms at any terminal is very low.
The NE panhandles has a low chance for a rain shower or
thunderstorms this afternoon with the threat ending by the
evening. Winds will be gusty from the north through the afternoon
and into the early evening. These winds will weaken for the
overnight and slowly shift to the south.

&&

.PRELIMINARY POINT TEMPS/POPS...
Amarillo TX                49  86  55  85 /   0   0  10  40
Beaver OK                  47  85  54  84 /   0   0  20  40
Boise City OK              45  85  50  78 /   0  10  20  50
Borger TX                  51  91  57  89 /   0   0  10  40
Boys Ranch TX              49  91  53  88 /   0   0  10  30
Canyon TX                  49  87  54  86 /   0   0  10  40
Clarendon TX               51  84  55  86 /   0   0  10  40
Dalhart TX                 45  86  48  81 /   0  10  20  40
Guymon OK                  47  87  52  81 /   0   0  20  40
Hereford TX                49  89  54  87 /   0   0  10  30
Lipscomb TX                49  85  56  86 /   0   0  20  40
Pampa TX                   50  86  56  85 /   0   0  10  40
Shamrock TX                51  84  56  87 /   0   0  10  40
Wellington TX              51  84  56  88 /   0   0  10  40

&&

.AMA WATCHES/WARNINGS/ADVISORIES...
TX...None.
OK...None.
&&

$$

SHORT TERM...29
LONG TERM....52
AVIATION...98