Area Forecast Discussion
Issued by NWS

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14
000
FXUS64 KEPZ 291104
AFDEPZ

Area Forecast Discussion
National Weather Service El Paso Tx/Santa Teresa NM
504 AM MDT Mon May 29 2017

.SYNOPSIS...
Southeast winds will bring gusty conditions to the west slopes of
the Franklin and Organ mountains this morning. They will diminish
by late morning, but will continue to transport moisture into the
region. This will result in isolated to scattered thunderstorms
today over most of the area, with better chances heading into
Tuesday as moisture becomes more widespread. A few storms may
produce strong but isolated downburst wind gusts and kick up some
dust. Drier air will work into the area from the southwest
towards the end of the week.

&&

.DISCUSSION...
Enhanced low level winds (VAD wind profile shows 25-30 knots just
off the deck) have resulted in strong downslope gusts along the
west-facing slopes of the Franklins and Organs this morning. Peak
gusts so far include 48 mph at Dripping Springs RAWS, and 47 mph
near the base of Transmountain Road, with gusts in the 30s across
other parts of West El Paso and the East Mesa in Las Cruces.
Similar to yesterday, winds will mostly diminish by mid-morning.

We have a challenging forecast in the short term as the 00z NAM
and GFS have major differences in the amount and depth of low
level moisture that will be present in the area this afternoon.

Observations at 09z show lower-40s dewpoints have pushed as far
west as ELP and the Otero Mesa...with mid-40s over Hudspeth
County. For 50s dews you`d have to go east of Pecos, TX or areas
south and east of the Davis Mountains. 60s are present over the
Rio Conchos valley in Chihuahua and the Big Bend in Texas. For
comparison, the 00z NAM and GFS both had lower-50s dewpoints into
Hudspeth County by 09z.

The differences only become more stark as we head into the
afternoon. By 18z the NAM holds on to mid-50s dewpoints at ELP
while the GFS mixes out to around 40. Model soundings show
the GFS is much shallower with the low level moisture. This has a
major impact in how unstable we will be by afternoon. The NAM has
CAPE values of 1500-2000 J/Kg in SW New Mexico while GFS is only
around 300-500 J/Kg. Considering observations, I`m inclined to
lean towards the GFS and the "drier" CAMs.

Models, including various CAMs, agree on the placement of the low
level moisture axis by afternoon, stretching from just south of
ELP and across the Boot Heel and nosing into Arizona south of the
Mogollon Rim. Lack of any very strong or obvious upper level
disturbances upstream, convection will likely initiate on the
higher terrain in the Gila Region and Sacramento Mountains, as
well as higher terrain in northern Chihuahua. Storms will drift to
the SE into the lower terrain, with outflow helping to initiate
storms in the deeper moisture over parts of Hudspeth County.
Precip chances/coverage for the ELP-LRU area may hinge on
convection initiating in the Sierra Madres spreading east, or
well-timed outflow boundary convergence. With low level moisture
expected to be a little more anemic, I cut PoPs off at about 40%
for ELP and LRU.

With drier conditions over the lowlands, a few storms may produce
stronger downburst winds, while QPF will be lower.

Precip chances will improve Tuesday as continued SE low level flow
slowly improves low level moisture. SW flow will bring in drier
air which will reduce the thunderstorm risk in far SW New Mexico
(especially the Bootheel) Wed-Thu, with precip all east of the
Rio Grande by Friday.

A weak upper disturbance moving across the Four Corners will push
all the moisture east of the CWA by the weekend.

&&

.AVIATION...
Updated the ELP TAF to include non-convective LLWS with 30 knots
just off the deck per VAD profiler and model soundings. LLWS will
diminish as we mix out a few hours after sunrise. Otherwise, main
issue today will be Isolated to Scattered showers and
thunderstorms, starting in the higher terrain around 18Z and
slowly trying to work their way into the lowlands. A few storms
could produce strong downburst or microburst gusts to around 50
knots.

&&

.FIRE WEATHER...
The bigger push of low level moisture overnight has lagged behind
expectations. While scattered thunderstorms are still expected to
develop over the higher terrain this afternoon, coverage over the
lowlands may be a little less widespread than earlier anticipated.
Dewpoints over the Gila may struggle to get out of the 30s, and
any storms that develop will have a greater risk of dry lightning
strikes and downburst winds as well.

Thunderstorm activity should slowly increase Tuesday as low level
moisture improves slightly, improving wetting rain chances
overall. Dry SW flow will begin to push the better moisture out of
the Bootheel Wednesday, with storms mostly shifting east of the
Rio Grande by the end of the week. Despite the drier air working
in, winds look to remain light heading into the weekend.

&&

.PRELIMINARY POINT TEMPS/POPS...
El Paso                 92  66  87  67 /  20  50  10  40
Sierra Blanca           87  63  83  62 /  40  60  40  50
Las Cruces              90  61  85  61 /  20  60  10  40
Alamogordo              88  59  83  59 /  20  40  40  50
Cloudcroft              62  44  60  43 /  60  40  60  60
Truth or Consequences   88  59  83  59 /  20  40  20  40
Silver City             85  52  82  55 /  30  40  40  60
Deming                  90  60  86  60 /  30  50  20  40
Lordsburg               90  59  88  59 /  30  20  10  30
West El Paso Metro      89  65  84  65 /  20  50  10  40
Dell City               90  59  86  61 /  10  30  20  50
Fort Hancock            91  65  88  66 /  30  60  20  50
Loma Linda              85  61  80  61 /  20  40  30  50
Fabens                  91  65  87  65 /  30  50  10  40
Santa Teresa            90  62  85  63 /  20  50  10  40
White Sands HQ          89  64  83  66 /  20  50  20  50
Jornada Range           89  60  84  61 /  20  50  10  50
Hatch                   91  59  87  59 /  20  50  10  50
Columbus                91  63  87  61 /  30  50  20  40
Orogrande               89  63  84  65 /  20  40  20  50
Mayhill                 71  47  68  49 /  50  40  60  60
Mescalero               73  48  70  48 /  50  40  60  60
Timberon                73  47  69  47 /  50  40  60  50
Winston                 79  45  76  44 /  30  50  40  60
Hillsboro               85  53  82  54 /  30  50  40  60
Spaceport               90  55  86  55 /  20  40  20  50
Lake Roberts            83  43  80  43 /  40  40  60  60
Hurley                  84  50  81  51 /  30  40  30  40
Cliff                   90  51  87  52 /  30  30  30  50
Mule Creek              86  55  86  55 /  30  30  30  40
Faywood                 86  53  82  54 /  30  40  30  40
Animas                  92  61  88  57 /  30  20  20  20
Hachita                 91  60  87  57 /  30  40  20  30
Antelope Wells          91  58  86  54 /  30  30  30  30
Cloverdale              87  57  82  52 /  40  10  30  20

&&

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

$$

25-Hardiman



USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.