-- Discussion containing changed information from previous version are highlighted. --
586
FXUS64 KEPZ 170532
AFDEPZ

Area Forecast Discussion
National Weather Service El Paso Tx/Santa Teresa NM
1132 PM MDT Mon Sep 16 2024

...New AVIATION...

.SYNOPSIS...
Issued at 1253 PM MDT Mon Sep 16 2024

Late season monsoon season moisture lingers over the Borderland
tonight and tomorrow. That means some shower and storm chances
this evening, continuing over eastern areas tomorrow. The rest of
the week will be dry as westerly flow aloft sweeps the moisture
east of the region. This weeks temperatures will be steady with
daily highs running slightly warmer than normal. Afternoon winds
will be occasionally slight breezy.

&&

.DISCUSSION...
Issued at 1253 PM MDT Mon Sep 16 2024

A slowly eastward advancing Pacific trough over the Western U.S.
is pushing the sub-tropical moisture eastward, over our region
for today through Tuesday. Surface dewpoints are up from 30
degrees a couple days ago, to the 50s, and PWATs are over 1.0" We
do have moderate dynamics and instability over our western areas,
with diffluence aloft, and CAPE values approaching 1000 J/kg. We
expect to see isolated to scattered showers and thunderstorms over
our western zones and north central zones though the afternoon and
into the early evening hours. For areas generally east of the Rio
Grande, including Far West Texas and S Otero lowlands, there is
less instability and forcing, thus we anticipate a lower potential
for storms, with isolated weak convection allowing for some
showers this evening.

For Tuesday, we will see the eastward shift of the moisture
channel continue as an upper low in the trough to our west begins
to lift NE across the Great Basin. For our area, with will mean
veering winds aloft, turning our flow more westerly. This means
drier air getting imported, with the moisture exiting to the east.
Our western areas should see a stark drying tomorrow with a sharp
line near the Rio Grande valley of dry air west and more moist air
east. This should result in a sunny and rain/storm free day west
of the Rio, and lingering shower/storm chances for area east of
the River. The east side precipitation potential should be waning
through the afternoon as the drier air slowly moves into these
areas.

Wednesday onward, with one possible exception, we expect a very
dry atmosphere over the forecast area, with plenty of sunshine,
and little to no chance of any precipitation. Temperatures will be
pretty steady as the synoptic pattern remains mostly static. That
pattern keeps the trough to our west and a minor ridge to our
east. That means we will be under a mostly dry SW flow pattern
between the two features that will keep our weather consistent day
to day. The possible exception referenced above is the set up of a
dryline just east and mostly outside of our CWFA. It does look to
make a westward push for Friday. If it can push in deep enough
over our eastern areas, we could see a sliver of our far eastern
portions of Otero and Hudspeth counties see some Friday storms,
while all other areas keep fair weather.

&&

.AVIATION...
-- Changed Discussion --
(06Z TAFS)
Issued at 1119 PM MDT Mon Sep 16 2024

VFR conditions are expected through the period across all of the
TAF sites with CIG FEW060-BKN250. There will be periods of SKC.
There may be a few ISO TS across the Borderland at least through
06Z Wednesday. The winds will be generally light and variable
except in the afternoon after 18Z. The winds then will become
gusty up to 29 kts and generally from the west and the west
southwest between 18 and 02Z Wednesday. They will subside
thereafter. There will be no reduction in the VSBY across the
runways.
-- End Changed Discussion --

&&

.FIRE WEATHER...
Issued at 1253 PM MDT Mon Sep 16 2024

A narrow channel of subtropical moisture is focused over the
region today, tonight, and part of Tuesday, on deep southerly
flow aloft. For this afternoon and early evening, we expect most
of the shower and storm activity to be west of the Rio Grande.
Tomorrow the western areas dry out, and the shower and storm
activity will be favored over areas east of the Rio Grande. Rain
will be spotty, hit or miss, with coverage generally isolated to
scattered. As the large trough to our west nudges closer to our
region overnight, the moisture will shift east, allowing much
drier air to sweep in from the west. This will mean a sharp drying
for all areas for Wednesday and the rest of the week. Afternoon RH
will drop back into the teens across the lowlands. For the full
week ahead, and into the weekend, temperatures will run pretty
steady due to an unchanging pattern across the west. Daily highs
will run 3-5 degrees warmer than normal.

For Friday we will be watching the dryline. Not a common feature
this time of year, but one will set up this week to our east.
Models are showing it back west into the SACs and Guadalupe
mountains and surrounding lowlands. That means we could see a bump
in moisture over Otero and Hudspeth county, with some low clouds,
showers and storms for Friday...while the rest of the region
remains quite dry. This moisture intrusion, if it happens, will be
very short-lived, as it gets quickly flushed back east for a
completely dry weekend across the area.

Ventilation through the week will be very good to excellent due to
relatively deep mixing, and mostly double-digit transport wind
speeds.

&&

.PRELIMINARY POINT TEMPS/POPS...
El Paso                  73  93  70  93 /  30  10  10   0
Sierra Blanca            65  88  63  89 /  10  10  20   0
Las Cruces               67  90  61  90 /  40  10   0   0
Alamogordo               67  90  60  90 /  30  30  10   0
Cloudcroft               50  67  46  66 /  20  50  10  10
Truth or Consequences    64  87  57  87 /  30  20   0   0
Silver City              57  78  52  80 /  40  30   0   0
Deming                   65  89  57  89 /  40  10   0   0
Lordsburg                63  85  56  86 /  30  20   0   0
West El Paso Metro       72  91  67  90 /  40  10  10   0
Dell City                68  93  65  94 /  10  10  10   0
Fort Hancock             69  95  66  95 /  10  10  10   0
Loma Linda               65  85  62  84 /  20  10  10   0
Fabens                   70  93  66  92 /  20  10  10   0
Santa Teresa             68  89  63  89 /  40  10  10   0
White Sands HQ           70  90  65  89 /  30  10   0   0
Jornada Range            66  88  59  88 /  30  20   0   0
Hatch                    66  90  57  90 /  40  10   0   0
Columbus                 68  90  61  90 /  30  10   0   0
Orogrande                66  88  60  87 /  30  20  10   0
Mayhill                  53  79  51  79 /  20  40  10  10
Mescalero                54  78  49  78 /  20  50  10  10
Timberon                 52  76  49  76 /  20  30  10  10
Winston                  52  79  44  80 /  20  20   0   0
Hillsboro                60  85  53  86 /  30  20   0   0
Spaceport                63  87  54  88 /  40  20   0   0
Lake Roberts             53  77  47  79 /  30  30   0   0
Hurley                   59  82  52  83 /  30  20   0   0
Cliff                    57  85  49  87 /  40  30   0   0
Mule Creek               58  78  52  79 /  50  40   0   0
Faywood                  60  83  54  82 /  30  20   0   0
Animas                   63  86  56  87 /  30  10   0   0
Hachita                  63  86  56  87 /  30  10   0   0
Antelope Wells           60  86  54  88 /  20  10   0   0
Cloverdale               59  80  54  81 /  10  10   0   0

&&

.EPZ WATCHES/WARNINGS/ADVISORIES...
TX...None.
NM...None.
&&

$$

FORECASTER...36-Texeira