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171
FXUS64 KMAF 300819
AFDMAF

Area Forecast Discussion
National Weather Service Midland/Odessa TX
319 AM CDT Tue Apr 30 2024

...New SHORT TERM, LONG TERM, FIRE WEATHER...

.SHORT TERM...
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(Today through Wednesday afternoon)
Issued at 308 AM CDT Tue Apr 30 2024

Buckle up, folks...it`s almost as if mother nature sees the
calendar changing from April to May and as you`d expect this time
of year, a round of strong to severe storms are expected to fire
off the dryline both this afternoon and Wednesday.

In response to lee troughing with weak quasi-zonal flow aloft,
efficient moisture return is underway this morning, pulling the
dryline back up against the higher terrain. With weak flow aloft,
the dryline doesn`t mix very far east by the afternoon, only really
making it to the central Permian Basin to Fort Stockton down south.
While not much environmental shear is present due to the weak flow
aloft (bulk shear is only about 20-30kts), very unstable air east of
the dryline (to the tune of 2000-2500 J/kg CAPE, with next to zero
CIN) will be enough to fire a storm or two off the dryline this
afternoon. Many members of the HREF are hinting at the first storm
to initiate will likely be across Pecos County where local
convergence will be maximized with Davis Mountains lee troughing.
From there, mesoscale influences will likely take hold and with
marginally long and straight hodographs in Pecos County, a splitting
supercell is the likely result - which is also backed up by numerous
HREF members. For what it`s worth, in this scenario, the right split
would turn into a classic Pecos County supercell with the left split
shooting northeastward into the Permian Basin...but it`s going to be
difficult to pin down exactly where storms set up. A few isolated
storms may also form along the dryline in other locations but the
consensus across the CAMs is that a few storms will likely form
somewhere, but vary in location from model to model. The result is
generally low coverage in storms, and PoPs remain 10-20% as such.
Should any strong storms develop and become rooted (especially in a
splitting supercell scenario), the primary hazards will be large
hail and damaging winds. Any storms that get going should start
around 19-20z, and fizzle out or move out of the area by 02-03z.
After any convection this afternoon/evening, outflow quickly shoves
the dryline westward, getting a much earlier start on the moisture
return compared to this morning. This resets the atmosphere for a
potentially busier day on Wednesday as the dryline won`t be able to
mix as far east by the time storms get going.

Come Wednesday afternoon, very similar environmental conditions
redevelop but notable differences occur due to a large trough
pushing its way into the Rockies. The subtle cooling aloft and
slightly higher surface dewpoints leads to more CAPE (~3000+
J/kg), but bulk shear is a tad weaker with the speed max from the
trough being too far away. With somewhat better synoptic forcing
and the dryline focused further west (with a more favorable
dryline bulge potentially), much greater storm coverage is
anticipated on Wednesday compared to what we`ll see later today.
The CAMs are all in agreement in this with the dryline firing
discrete storms initially from the Permian Basin down through
Pecos County and gradually growing upscale through the evening.
Damaging winds and large to very large hail remain the main
concerns, but even a very low tornado potential presents itself,
especially where convective outflow can locally enhance low level
shear.

Temperature wise, the afternoon highs will be quite hot (in the
upper 80s and 90s) which aid in easily reaching convective
temperature and leading to an uncapped environment. Due to the
strong moisture return both tonight and Wednesday night, low
temperatures stay hung up in the low to mid 60s for most.

-Munyan
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&&

.LONG TERM...
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(Wednesday night through Monday)
Issued at 308 AM CDT Tue Apr 30 2024

After a couple of active days, much calmer conditions are expected
Thursday as the dryline shoves low level moisture well to our east.
Temperatures will stay warm with most locations into the 90s minus
the higher terrain where elevation will keep highs near 80.

Another active weather period looks to begin Friday initially with
the passage of a cold front. This front has trended weaker than
previous model runs, but still is forecast to push to at least the
higher terrain Friday. SW flow aloft above the cooler airmass along
with some sun could help generate a few elevated showers and storms,
mainly across the Permian Basin and Lower Trans Pecos. High
temperatures will cool slightly behind the front generally into the
low to mid 80s, but remain very warm south and west of the Pecos
River. Convective activity looks to increase over the weekend as mid
level flow strengthens amid a sharpening dryline over the region. We
could see widespread storms, some severe, across much of the
Permian Basin both days this weekend. It`s still too early to get
into the details on exact timing and intensity of the storms, but
it would be a good idea to plan on at least some storms if you
have outdoor plans.

Deeper, zonal flow increases next week giving way to much drier and
hotter conditions across the region.
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&&

.AVIATION...
(06Z TAFS)
Issued at 1219 AM CDT Tue Apr 30 2024

VFR prevails with relatively light south-southeasterly winds.

&&

.FIRE WEATHER...
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Issued at 308 AM CDT Tue Apr 30 2024

While most locations east of the Pecos River have seen a green-up,
further west we have not seen a wetting rainfall in quite a while.
After a brief break, critical fire weather conditions return out
west Wednesday. Winds remain light this afternoon, but RHs will
fall to critical levels across the higher terrain and adjacent
plains. By Wednesday, winds increase over Southeast New Mexico
and the Guadalupe Mountains and combine with very critical fuels.
Along with RHs near 5 percent we are looking at critical to
locally extreme fire weather conditions, especially over much of
Chaves county. Drier conditions become more widespread Thursday,
but winds will weaken some. More moist conditions arrive for most
of the area Friday into the weekend, but the higher terrain looks
to remain very dry.
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&&

.PRELIMINARY POINT TEMPS/POPS...
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Big Spring               92  66  89  64 /  10  10  30  40
Carlsbad                 93  55  94  59 /   0   0  10   0
Dryden                   94  69  88  67 /  10  10  30  20
Fort Stockton            94  65  91  61 /  20  10  50  20
Guadalupe Pass           87  59  87  57 /   0   0   0   0
Hobbs                    90  58  91  56 /   0   0  10  10
Marfa                    88  51  87  51 /   0   0  10   0
Midland Intl Airport     92  66  89  64 /  10  10  30  30
Odessa                   92  67  89  65 /  10  10  30  30
Wink                     95  63  94  61 /   0   0  20  10
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&&

.MAF WATCHES/WARNINGS/ADVISORIES...
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TX...Fire Weather Watch from Wednesday afternoon through Wednesday
     evening for Guadalupe Mountains Above 7000 Feet-Guadalupe
     and Delaware Mountains.

NM...Fire Weather Watch from Wednesday afternoon through Wednesday
     evening for Chaves Plains-Eddy Plains-Sacramento Foothills
     and Guadalupe Mountains.
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&&

$$

SHORT TERM...16
LONG TERM....29
AVIATION...16