NWS El Paso, TX wrote its last area forecast discussion before the first event at Aug 14, 5:09 AM MST, 5 hours 6 minutes earlier.
Area forecast discussion, Aug 14, 5:09 AM MST, 5 hours 6 minutes before
Area Forecast Discussion
National Weather Service El Paso TX/Santa Teresa NM
609 AM MDT Sat Aug 14 2021
.UPDATE...12Z TAF ISSUANCE...
Plenty of nocturnal shower and thunderstorm activity across Far
West Texas and Southern New Mexico as we head into the early
morning hours. Scattered showers and isolated thunderstorms are
producing MVFR to IRF conditions with rain shafts lowering VSBY to
1-3 SM and lowering CIGS to 2-3kft AGL. Plenty of mtn obscurations
too. These will likely diminish in coverage through the morning,
but the diurnal heat cycle should generate a new batch of showers
and thunderstorms by late AM/early PM. Thus some breaks in the
clouds, but still plenty through the period. Winds generally E in
the 5-10kt range.
&&
.PREV DISCUSSION...406 AM MDT Sat Aug 14 2021...
.SYNOPSIS...
Areas of heavy rain and isolated instances of flash flooding
remain possible this afternoon and into the overnight across much
of the area, with the threat shifting to the international border
into Sunday. Scattered thunderstorms remain possible into the
early to middle portions of next week, especially over area
mountains, with temperatures between 86 and 92 degrees generally.
&&
.DISCUSSION...
.SHORT TERM...
It's August, and we are in the heart of the traditional SW monsoon
season. The current and projected PWAT values across the CWFA are
1.50" to 1.80" according to model consensus. The surface dewpoints
are in the mid-60s tonight, and the models keep them in the 60s
through the day today. Both of these numbers (PWATs and dewpoints)
are above average. This means the atmosphere across the Borderland
is ripe with moisture for more storms and rain. The synoptic pattern
across the southwest doesn't really provide the region with any
large scale forcing, or any features that would promote or focus
storm development over our region, but we don't/won't need that to
generate another round of showers and thunderstorms today. All that
is needed, with this moist and conditionally unstable airmass, will
be forced upslope flow over higher terrain, and surface heating,
with any breaks in the abundant cloud cover. The day will overall
stay cooler than average, but also quite muggy with the high
humidity.
With all the moisture, clouds will likely win over sunshine. Any
sunshine we do get will feedback with more cloud development. Given
the very moist atmosphere, we have high POPS with scattered to
numerous showers and thunderstorms in for forecast for all areas
again today and well into the evening tonight. Storms should be
tracking from SSE to NNW today at a relatively slow rate of 5-15
mph. With much of the area having already seen moderate to heavy
rainfall, our soils are wet and, in many cases saturated. This means
very efficient, and proficient, rain-making storms with heavy rain
and flash flooding, ponding expected. In urban areas especially, the
rain rates and amounts could lead to life-threatening flooding
scenarios. Thus the Flash Flood Watch continued through midnight
tonight.
&&
.LONG TERM...
Sunday, our moisture across northern areas begins to slightly
decrease, but most of the area will continue with anomalously
moist PWs. As a result, thunderstorm chances will remain
throughout the day, with heavy rain and isolated flash flooding.
Some of the main forcing aloft will be lost, but it actually
seems pretty energetic in the atmosphere, especially southern
portions, so lift may be ample enough for decent storm coverage.
Heading into the early to middle portions of next week, we have a
trough just clipping NE areas of the CWA, with perhaps an
associated weak sfc convergent zone swinging through. May be the
focus for isolated storm coverage Monday evening into the
overnight hrs, but prior, area mountains will be favored,
especially the Gila. Moisture decreases a bit, but still
remaining in the 1.3" range for PW during the afternoon, and
increasing into the overnight. Tuesday and Wednesday seem a lot
more typical monsoonal on the ECM and CMC, with the GFS a bit more
scattered potential across the lowlands. Not the easiest upper
level pattern to discern during the later portions of next week
as a few very small scale features emerge to impact thunderstorm
coverage, so for now thinking scattered mtns and iso lowlands, but
if some of these features push west into the Borderland, the
coverage could increase. Temperatures will remain in the 85 to 92
degree range most of the long term period with light to mildly
breezy winds outside of thunderstorm outflow.
&&
.FIRE WEATHER...
Fire weather concerns are next to nil across the region given the
deep atmospheric moisture, high low-level relative humidity
values, abundant expected cloud cover, much cooler than normal
temperatures, and widespread wetting rains expected through the
weekend.
On the other hand, heavy rain and flash flooding will be a concern
for anyone out in the field and without a source for current weather
situational awareness. Flooding of creeks, arroyos, washes is
possible and may cut off travel routes, or threaten personal safety.
In addition, heavy rain over any sensitive burn scar is likely to
produce heavy runoff and debris flows.
Moisture levels do wain a bit for much of the workweek ahead, but we
never completely dry out so, although with lesser coverage, we do
expect at least isolated to scattered showers and storm much of the
week. Temperatures will warm, and Rh will drop, but still be well
above critical thresholds. Models suggest a return of deeper
monsoon moisture by the end of the week and next weekend, with an
associated increase in storm and rain coverage.
&&
&&
.PRELIMINARY POINT TEMPS/POPS...
El Paso 78 66 81 67 / 70 70 60 20
Sierra Blanca 75 61 75 61 / 60 50 70 20
Las Cruces 76 63 81 63 / 70 70 60 20
Alamogordo 77 62 81 63 / 80 60 60 20
Cloudcroft 57 46 60 46 / 100 80 70 20
Truth or Consequences 79 62 81 63 / 70 60 50 20
Silver City 73 58 75 58 / 70 70 60 30
Deming 78 63 81 63 / 70 70 60 30
Lordsburg 81 65 80 63 / 70 60 60 30
West El Paso Metro 79 67 82 68 / 70 70 60 20
Dell City 77 63 79 63 / 60 50 60 20
Fort Hancock 82 66 83 66 / 60 60 60 20
Loma Linda 71 61 73 61 / 70 70 70 20
Fabens 78 67 81 66 / 70 60 60 20
Santa Teresa 77 65 80 65 / 70 70 60 20
White Sands HQ 75 65 80 65 / 80 70 70 20
Jornada Range 74 63 78 63 / 70 60 60 20
Hatch 75 63 79 63 / 70 60 60 20
Columbus 78 65 79 65 / 70 70 60 30
Orogrande 75 63 79 63 / 80 60 60 20
Mayhill 62 53 71 53 / 90 70 70 20
Mescalero 64 51 71 51 / 90 70 70 20
Timberon 62 51 67 50 / 90 70 80 20
Winston 73 53 76 53 / 70 60 50 20
Hillsboro 74 60 78 59 / 80 70 60 20
Spaceport 76 62 80 62 / 70 60 50 20
Lake Roberts 77 54 77 53 / 70 60 60 20
Hurley 76 59 78 58 / 70 70 60 30
Cliff 82 59 83 59 / 60 60 50 30
Mule Creek 81 60 78 57 / 60 50 50 30
Faywood 73 60 76 59 / 70 70 60 30
Animas 80 62 79 62 / 70 70 60 40
Hachita 80 62 77 62 / 70 70 60 30
Antelope Wells 80 63 79 63 / 70 70 70 50
Cloverdale 76 60 75 60 / 70 70 70 50
&&
.EPZ WATCHES/WARNINGS/ADVISORIES...
NM...Flash Flood Watch through this evening for NMZ401>417.
TX...Flash Flood Watch through this evening for TXZ418>424.
&&
14-Bird/35/14