759 
fxus64 kepz 191939 
afdepz 


Area forecast discussion 
National Weather Service El Paso Texas/Santa Teresa nm 
139 PM MDT Friday Mar 19 2010 


Synopsis... 
an upper level low pressure system with a strong cold front will 
move across southern New Mexico and western Texas tonight and 
Wednesday morning. As a result there will be lowland rain showers 
and mountain snows tonight with much cooler temperatures occurring 
Saturday and Saturday night. High pressure and westerly winds will 
bring warmer dry weather on Sunday and Monday. Another low 
pressure system with a cold front will cause a few rain showers 
and mountain snows Tuesday and Wednesday. 


&& 


Discussion... 
active pattern in progress this afternoon as split flow will 
continue to engender unsettled weather. Early this afternoon upper 
low in southerly branch was located over central Arizona with 
northerly jet trough moving into the central rockies. These systems 
will phase late this afternoon and this evening as 120 knots upper 
jet streak causes northern system to amplify/dig toward the County Warning Area. By 
06z a single high amplitude trough will be moving west to east 
through New Mexico and western Texas with pronounced DPVA and 
associated dynamic upward forcing. Concurrently a strong cold 
extending across northern New Mexico this afternoon will 
accelerate southward and push through the entire area by 08z 
Saturday. 


While Continental flow trajectories preclude significant moisture 
advection at low and middle levels, strong dynamic forcing and weak 
instability should induce a few lowland rain showers with snow 
over the mountains. Heaviest snows will be over the sacramento's 
where upslope winds will support snow amounts around advisory 
levels. Most precipitation should end before noon Saturday as 
trough moves east of The Rockies. However strong cold air 
advection behind the front will keep tomorrows high temperatures 
15 to 20 degrees below normal. Saturday night/early Sunday the 
combination of light winds...clear skies and low dewpoints will 
result in temperatures falling below freezing most lowland areas 
by sunrise Sunday. 


Upper ridge Sunday followed by westerly winds Monday will cause 
dry weather with warming temperatures. However complex active 
weather scenario begins once again on Tuesday as southerly branch 
low moving across northern Baja California phases with upper low moving into 
Great Basin. After trough merger an upper low with another cold 
front will move into the County Warning Area bringing a threat of lowland rains 
and mountain snows along with cooler temperatures. 


&& 


Aviation...valid 20/00z-21/00z... 
strong upper level trough over the central rockies will move into 
the County Warning Area tonight with backdoor frontal passage around 03z and upper air tropa 
around 12z. From 00z-03z: sct060 scattered-bkn100 bkn200 above ground level with surface winds 
270-30025g35kt isolated -shra NE of an elp-tcs line. MDT occasional gtr turbulence 
over and near mountains 03z-18z sct040 scattered-bkn080-120 broken-ovc15-200 above ground level. 
Surface winds 06012g22kt with g 30-35 kts west facing slopes/passes. 
IFR-LIFR Sacramento Mountains in -shsn with mountains occasionally obscured and light to MDT 
icgicip above 6000 feet mean sea level to 12000 feet mean sea level. After 18z: sct070 sct250 
above ground level. Surface wind 020/10kt. 


&& 


Fire weather... 
fire weather conditions in the desert lowlands below 6000 feet will be 
elevated and will approach and or reach critical values for short 
intervals (but not for 3 hours) from 21z-23z today in an area 
covering Hidalgo County south of Interstate 10 eastward to El Paso 
then eastward in far West Texas south of the Otero nmex County line. 


A strong upper level trough of low pressure over the central rockies 
remains on schedule and will move into the Borderland 
late this afternoon through Saturday morning. Winds will become gusty 
this afternoon and some rain showers will develop from the Gila 
WIlderness across to the Sacramento Mountains. Snow will remain at 
just the highest elevations this evening but the snow level will 
fall rapidly over the Sacramento Mountains Saturday morning as a 
cold front pushes west across the area. Locally heavy amounts of snow 
are possible in the sacrament0 mountains in Lincoln County. This cold 
front will cool the area significantly for the weekend...with drops of 
15 degrees or more for saturday's highs. Skies will become clear for 
the end of the weekend and first part of next week...while 
temperatures rebound to back above normal for Monday and Tuesday. 
Another storm system moves in later Tuesday and Wednesday bringing 
another threat of showers. 


&& 


Preliminary point temps/pops... 
El Paso 41 53 30 63 36 / 20 0 0 0 0 
Sierra Blanca Texas 41 52 26 61 34 / 20 0 0 0 0 
Las Cruces 39 52 28 62 33 / 20 0 0 0 0 
Alamogordo 39 51 26 60 31 / 30 10 0 0 0 
Cloudcroft 22 28 11 40 19 / 60 20 0 0 0 
Truth or Consequences 37 50 25 59 29 / 30 0 0 0 0 
Silver City 32 46 20 56 27 / 20 0 0 0 0 
Deming 39 53 26 62 31 / 20 0 0 0 0 
Lordsburg 39 52 27 62 33 / 10 0 0 0 0 


&& 


Epz watches/warnings/advisories... 
nm...Winter Weather Advisory from 6 PM this evening to 6 am MDT 
Saturday for nmz025. 


Texas...none. 
&& 


$$ 


05 rogash/20 novlan