296
FXUS64 KMAF 070910
AFDMAF

Area Forecast Discussion
National Weather Service Midland/Odessa TX
310 AM CST Thu Nov 7 2024

...New SHORT TERM, LONG TERM...

.KEY MESSAGES...
Updated at 257 AM CST Thu Nov 7 2024

 - There remains a high chance (>70%) for significant rainfall
   across many areas north and east of the Pecos River on Thursday
   and Friday with rainfall amounts greater than an inch for some.
   A Flood Watch is in effect for the eastern Permian Basin
   beginning this evening and continuing through Friday morning.

 - There is a low chance (<30%) of severe thunderstorms Thursday
   afternoon and night across the Permian Basin and Lower Trans
   Pecos. The main threats with any severe thunderstorms will be
   large hail, damaging winds, and a tornado or two. Take extra
   caution with nighttime storms and stay weather aware!

 - Cold temperatures in the 30s and 40s are expected Saturday
   morning across the area. There is about a 50% chance for a
   light freeze across northern Lea and Eddy Counties, the Marfa
   Plateau, and the higher elevations of the Davis and Guadalupe
   Mountains.

&&

.SHORT TERM...
(Today through Friday afternoon)
Issued at 257 AM CST Thu Nov 7 2024

A very busy short-term forecast is in store for much of the southern
Great Plains with a multitude of different weather events to
discuss. Let us begin with this morning. At this time, a large upper-
level low is centered near the Arizona/New Mexico border with weak
ridging over the Southeast. At the surface, a weak area of low
pressure is beginning to take shape very near the I-10/I-20 split in
the lee of the Davis Mountains. A cold front, soon to be warm front,
extends northeast from this developing low pressure, roughly along
the I-20 corridor. To the north of the cold front and west of the
low, cooler temperatures have begun to filter into the the region as
many locations fall into the 40s and even some upper 30s. A few
showers are also possible across this area, as large scale forcing
begins to increase over the region. Further to the east, ahead of
the developing low, moist return flow is keeping temperatures milder
and in the 50s to start the day.

Heading into the afternoon, the upper-low remains nearly stationary
over the Arizona/New Mexico border. The developing surface low
pressure remains near the I-10/I-20 split and our cold front may now
slowly lift back north as an effective warm front. Temperatures
remain cool behind the developing low and warm front with most of
these locations struggling to get out of the upper 50s to low 60s.
Ahead of these features, temperatures climb back into the 60s to low
70s for many, though cloud cover should limit daytime heating for
many. Shower and thunderstorm coverage will also continue to
increase over most the region. Across the Lower Trans Pecos and
eastern Permian Basin, a chance of showers and thunderstorms is
expected within a warm, moist advection region within the
strengthening southeasterly return flow. Across southeast New Mexico
and the northern Permian Basin, isentropic lift over the warm front
and increasing ascent ahead of the upper-low should support more
widespread showers and thunderstorms through the afternoon. While
most of these thunderstorms should remain in more modest
instability, the strongest thunderstorms could pose a risk of large
hail and damaging winds. While most models keep the central Permian
Basin clear through much of the day, any thunderstorms that develop
could be strong within this area as daytime heating destabilizes the
environment.

While the aforementioned activity will need to me monitored, the
main event begins this evening and overnight into Friday morning.
Our upper-low will begin to accelerate east into the southern Rocky
Mountains from the Arizona/New Mexico border. This will not only
cause large scale ascent to become maximized, but begins to push our
surface low pressure towards the northeast as well. The current
expectation is that as the cold front develops with the lifting
surface low pressure, a broken line of thunderstorms will begin to
form. These thunderstorms are likely to congeal into multiple
organized thunderstorm complexes as they slowly lift off towards the
northeast. There could also be more isolated thunderstorms that form
out ahead of this line, further into the warm sector as height falls
continue over the region.

At this time, the main severe weather concern with these
thunderstorms is mainly large hail with any severe thunderstorms
that develop. Cold temperatures aloft, plentiful wind shear, and
modest instability should support this threat well into the
overnight hours. Damaging wind gusts may also be possible,
especially with the developing thunderstorm complexes, though the
nocturnal inversion should begin to limit this threat into the
overnight hours. While a lesser threat, a tornado or two can`t be
completely ruled out. The main corridor for this threat would be
with any pre-frontal thunderstorms in the open warm sector,
especially early this evening and near the warm front should any
develop. This remains a more conditional threat though.

The other concern is the potential for flash flooding. While many
areas across the northern and eastern Permian Basin are expected to
receive significant rainfall, the eastern Permian Basin has the best
opportunity to receive multiple rounds of torrential rain. This will
be supported by a chance of afternoon thunderstorms within the warm
advection regime and as the developing low lifts off to the
northeast. Once any precipitation activity enters the eastern
Permian Basin tonight, most of the thunderstorms should be
matured as everything slowly moves off to the northeast. Within
any convection, very high rainfall rates may support several
inches per hour, leading to rapid accumulations and the potential
for flash flooding. With this expectation in mind, a Flood Watch
has been issued for much of the eastern Permian Basin from this
evening through Friday morning. Areas that received recent
rainfall or that receive multiple rounds of thunderstorms today
and tonight will be the most likely to have flash flooding
potential within this watch area.

By Friday afternoon, things begin to gradually wind down across the
region. By late morning, the surface low pressure and accompanying
front should be departing the area to the east as the main upper-low
moves onto in the Great Plains. This will bring cooler and drier air
in behind the system, gradually bringing an end to any shower or
thunderstorm activity from west to east. By late afternoon, the sun
should begin to come out across a large portion of the area, as the
last of the precipitation exits the region. Temperatures respond to
this cooler airmass with upper 50s and lower 60s for many, though
70s hold on over the Rio Grande where they remain high and dry. This
period will mark the end of the active weather for the foreseeable
future.

-Chehak

&&

.LONG TERM...
(Friday night through Wednesday)
Issued at 257 AM CST Thu Nov 7 2024

All is quiet during the long term forecast period. While it is
expected to be chilly Saturday morning as surface high pressure
fills in behind our departing weather system, this is the only
weather to really note. Widespread 30s and low 40s will necessitate
a jacket for all to start the day. In addition, our first widespread
light freeze may impact portions of southeast New Mexico as well as
the higher elevations. Despite this cold start, zonal flow quickly
sets in over the southern Great Plains, resulting in a quick warm up
by Saturday afternoon. Most locations see sunny skies and
temperatures back to near normal in the upper 60s and low 70s. The
warm and dry weather is only expected to continue Sunday into early
next week. Above normal temperatures return as most areas climb into
the upper 70s and low 80s. No rainfall is expected through this
period as dry zonal flow keeps skies mostly sunny. By the middle of
next week, a cold front may push through the region as the next
trough passes north of southern Great Plains. This would
unfortunately keep everyone dry, but may also offer near normal
temperatures in response. With the extended remaining dry, all hope
is in the short-term for rainfall.

-Chehak

&&

.AVIATION...
(06Z TAFS)
Issued at 1022 PM CST Wed Nov 6 2024

A cold front is making its way to the I-20 corridor where is will
stall much of the next 24 hours. Gusty north winds are affecting
these terminals with lighter winds to the south. MVFR cigs are
expected to develop along and north of the front by sunrise.

&&

.PRELIMINARY POINT TEMPS/POPS...
Big Spring               65  56  64  40 /  60  90  60  10
Carlsbad                 55  42  58  34 /  20  60  10   0
Dryden                   77  59  76  50 /  20  70  40  10
Fort Stockton            71  48  67  39 /  20  60  10  10
Guadalupe Pass           54  35  53  38 /  20  40   0   0
Hobbs                    63  43  57  33 /  40  80  20   0
Marfa                    72  39  60  34 /  10  40   0   0
Midland Intl Airport     66  52  63  39 /  50  90  30  10
Odessa                   66  52  63  40 /  50  90  30  10
Wink                     68  45  64  35 /  30  80  10   0

&&

.MAF WATCHES/WARNINGS/ADVISORIES...
TX...Flood Watch from this evening through Friday morning for Borden-
     Glasscock-Howard-Mitchell-Reagan-Scurry.

NM...None.
&&

$$

SHORT TERM...91
LONG TERM....91
AVIATION...29